Age-Related Histomorphological Changes in Human Kidneys: A Cadaveric Study

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Even though a lot of research has been done on Western cultures, there isn't much information about how kidneys age in South Asian populations, like Bangladesh. Objective: The goal of this study was to look at how the structure of human kidneys varies with age in different age groups using cadaver samples from Bangladesh. Methodology : At Dhaka Medical College, researchers did a descriptive cross-sectional study on 100 kidneys from unclaimed bodies. The bodies were divided into four age groups: 10–19, 20–39, 40–59, and 60 years or older. We assessed morphometric characteristics such kidney weight, length, width, thickness, and volume. We also used hematoxylin and eosin staining to look at the number and size of glomeruli. ANOVA and unpaired t-tests were used to do the statistical analysis. Results: The size and volume of the kidneys were highest in the 20–39 years group and dropped a lot in older age groups (≥ 60 years). As people got older, the number of glomeruli per mm² went down, but the diameter of the glomeruli went up. This is a sign of compensatory hypertrophy. Histological results also showed that older kidneys had more interstitial fibrosis and thicker blood vessels. These findings support global patterns of kidney aging and draw attention to unique structural changes in South Asia. Conclusion: The work gives important baseline histomorphological information about how kidneys age in a South Asian population, showing that the structure of kidneys starts to break down after age 60. To find and treat age-related kidney disorders early, it's important to understand these changes, especially in places like Bangladesh where resources are limited. Renal Aging Kidney Morphometry Glomeruli Interstitial Fibrosis Figures Figure 1 Background The human kidney is a critical organ that keeps the body in balance by filtering, reabsorbing, and secreting things [ 1 ]. As we get older, the structure and function of the kidney change a lot. As people become older, their kidneys go through a lot of structural and functional changes that can affect how the kidneys work as a whole and make them more likely to develop kidney-related diseases [ 2 , 3 ]. Changes in the kidneys that happen with age include glomerulosclerosis, tubular atrophy, interstitial fibrosis, and thickening of the blood vessels [ 4 ]. All of these changes lead to a reduction in kidney function [ 5 ]. These changes are very important for doctors because they affect how often and how many people get chronic kidney disease (CKD) and end-stage renal disease (ESRD) around the world, especially in older people [ 6 ]. About 10% of people throughout the world have CKD. Older folks are more likely to have it because they lose nephrons and their kidneys don't work as well as they used to [ 7 , 8 ]. In Western countries and Europe, the risk of CKD goes up a lot after age 60[ 9 ]. Almost 30% of people over 70 have some kind of kidney problem [ 10 ]. On the other hand, South Asia, which includes Bangladesh, has a double burden of communicable and non-communicable illnesses. The number of people with CKD is rising because the population is becoming older, and more people are getting diabetes and high blood pressure [ 11 , 1 ]. There isn't enough histomorphological data on how kidneys age in these people that is specific to the area, which shows how much more research has to be done [ 2 , 3 ]. The main reason why kidney function gets worse as people get older is because they lose nephrons. Studies reveal that by the eighth decade of life, the number of nephrons is cut in half [ 3 , 12 ]. Histopathological tests show that renal aging is characterized by glomerular hypertrophy, increased mesangial matrix deposition, and arteriolar hyalinization [ 1 , 4 ]. Thickening of the tubular basement membrane and interstitial fibrosis make functional decline worse, making people more likely to get acute kidney injury (AKI) and chronic kidney disease (CKD) [ 13 , 14 ]. Systemic disorders that are common in older people, such as hypertension and atherosclerosis, make these structural problems worse [ 6 , 15 ]. There has been a lot of research on how kidneys age in Western populations, but there is still not much data from low- and middle-income countries (LMICs), such as Bangladesh and South Asia [ 16 , 17 ]. Differences in genetics, the environment, and access to healthcare may all play a role in the different ways that different ethnic groups' kidneys age [ 1 , 4 ]. Cadaveric studies are a one-of-a-kind way to look at histomorphological changes without the effects of treatment, which helps us understand how aging happens on its own [ 4 , 7 ]. This study looks at how the histomorphology of human kidneys changes with age by looking at cadavers. It focuses on changes in the glomeruli, tubules, blood vessels, and interstitial tissue [ 1 , 3 ]. This study will help us learn more about how kidneys age in different groups of people, especially areas that haven't been researched much before, like South Asia [ 8 ]. The results may help find and treat age-related kidney problems early, especially in places with few resources. This work is necessary since kidney illness is becoming more common around the world and we need more detailed histopathology data to help with clinical management and public health measures. Finding out what causes renal aging on a structural level could help create targeted treatments to slow down functional decline in at-risk groups. Methodology The current study was a descriptive cross-sectional analysis that took place in the Department of Anatomy, Rajshahi Medical College, from July 2024 to June 2025. It used 100 human kidneys that had been taken from unclaimed deceased bodies at the Dhaka Medical College morgue. We looked examined the right and left kidneys of both male and female cadavers. Specimens with birth defects, injuries, kidney disease, or decomposition were not included. There were four groups of kidneys based on age: A (10–19 years), B (20–39 years), C (40–59 years), and D (60 years and beyond). After they were collected, the kidneys were cleaned, labeled, fixed in 10% formalin, and prepared for both morphometric and histological investigation. Using calibrated instruments and the ellipsoid formula, we assessed morphometric parameters such kidney weight, length, breadth, thickness, and volume. Five pairs of kidneys from each group were cut up, processed, and stained with hematoxylin and eosin for histological assessment. A stage micrometer and an ocular micrometer were used to measure the number of glomeruli per square millimeter and the average diameter of glomeruli. Three fields were measured on each slide. We used SPSS version 16.0 to do statistical tests such the mean, standard deviation, ANOVA, and unpaired t-tests. Rajshahi Medical College gave the go-ahead for the study. Microscopes, dissection instruments, staining chemicals, and digital measurement equipment were some of the tools employed. Even though the methodology was thorough, there were some problems that could affect the generalizability of the results. These included unequal sample sizes among age groups, a small sample size, no examination of sex differences, and a paucity of available unclaimed cadavers. Still, the study gives us useful information about how the kidneys change with age by looking at cadavers. Results This study investigated at different morphometric measurements of the left and right kidneys in four age groups: A (10–19 years), B (20–39 years), C (40–59 years), and D (≥ 60 years). There was a big difference in kidney weights with age (p < 0.001). The left kidney weighed 85.04 ± 2.30 gm in group A, then it got heavier in group B, reaching a maximum of 98.67 ± 3.95 gm. In group C, it got lighter again, to 94.75 ± 0.95 gm, and in group D, it was even lighter, to 85.33 ± 2.48 gm. Table 1 Kidney Weights (gm) Across Different Age Groups Age Group Age Range N Left Kidney Mean ± SD (gm) Left Kidney 95% CI (gm) Right Kidney Mean ± SD (gm) Right Kidney 95% CI (gm) A 10–19 9 85.04 ± 2.30 83.27–86.81 84.88 ± 2.03 83.32–86.45 B 20–39 29 98.67 ± 3.95 97.17–100.17 95.80 ± 7.05 89.31–102.29 C 40–59 6 94.75 ± 0.95 93.76–95.75 94.84 ± 1.47 93.28–96.39 D ≥ 60 6 85.33 ± 2.48 82.72–87.95 85.19 ± 2.64 82.41–87.97 Kidney F-value p-value Interpretation Left Kidney 3.604 0.001 Statistically significant difference (p < 0.001) Right Kidney 95.871 0.001 Statistically significant difference (p < 0.001) *ANOVA Test Results The weight of the right kidney was the same: it was 84.88 ± 2.03 gm in group A, 95.80 ± 7.05 gm in group B, and 85.19 ± 2.64 gm in group D. The lengths of the kidneys followed a similar pattern: in group A, the left kidney was 8.44 ± 0.87 cm long, in group B it was 9.56 ± 0.98 cm long, and in groups C (8.55 ± 0.50 cm) and D (8.42 ± 0.27 cm) it got shorter. The length of the right kidney was similar, ranging from 8.45 ± 0.40 cm in group A to 9.41 ± 1.03 cm in group B and lower values in older groups. Table 2 Kidney Lengths (cm) Across Different Age Groups The left kidney in group B was the widest, measuring 4.16 ± 0.44 cm, while the right kidney was the widest, measuring 3.95 ± 0.57 cm. Group D had the narrowest breadth, with the left kidney measuring 3.88 ± 0.62 cm and the right kidney measuring 3.65 ± 0.34 cm. The same trend held true for thickness measurements: the left kidney was 3.28 ± 0.40 cm thick in group B and 2.73 ± 0.36 cm thick in group D, and the right kidney was 3.27 ± 0.30 cm thick in group B and 2.76 ± 0.44 cm thick in group D. Age Group Age Range N Left Kidney Mean ± SD (cm) Left Kidney 95% CI (cm) Right Kidney Mean ± SD (cm) Right Kidney 95% CI (cm) A 10–19 9 8.44 ± 0.87 8.11–8.78 8.45 ± 0.40 8.14–8.76 B 20–39 29 9.56 ± 0.98 8.63–9.70 9.41 ± 1.03 8.33–9.50 C 40–59 6 8.55 ± 0.50 8.01–9.08 8.70 ± 0.40 8.27–9.12 D ≥ 60 6 8.42 ± 0.27 8.21–8.63 8.38 ± 1.08 7.96–8.79 Table 3 Kidney Breadth (cm) Across Different Age Groups Group B had the most kidney volume, with the left kidney measuring 58.18 ± 9.35 cm³ and the right kidney measuring 57.67 ± 17.86 cm³. The volumes for Group D were the smallest: 47.72 ± 3.20 cm³ on the left and 50.73 ± 8.16 cm³ on the right. Age Group Age Range N Left Kidney Breadth Mean ± SD (cm) 95% CI Left Kidney (cm) Right Kidney Breadth Mean ± SD (cm) 95% CI Right Kidney (cm) A 10–19 9 4.06 ± 0.37 3.77–4.35 3.82 ± 0.28 3.60–4.04 B 20–39 29 4.16 ± 0.44 3.99–4.33 3.95 ± 0.57 3.73–4.16 C 40–59 6 4.05 ± 0.36 3.66–4.43 3.76 ± 0.21 3.54–3.99 D ≥ 60 6 3.88 ± 0.62 3.22–4.53 3.65 ± 0.34 3.50–3.80 Table 4 Kidney Thickness (cm) Across Different Age Groups Finally, group B had the most glomeruli per mm², with 9.33 ± 0.46 in the left kidney and 9.27 ± 0.44 in the right kidney. The number of glomeruli per mm² went down in older groups. Age Group Age Range N Left Kidney Thickness Mean ± SD (cm) 95% CI Left Kidney (cm) Right Kidney Thickness Mean ± SD (cm) 95% CI Right Kidney (cm) A 10–19 9 3.04 ± 0.46 2.86–3.21 3.02 ± 0.36 2.66–3.20 B 20–39 29 3.28 ± 0.40 2.98–3.59 3.27 ± 0.30 3.04–3.51 C 40–59 6 3.07 ± 0.16 2.60–3.50 3.06 ± 0.58 2.45–3.68 D ≥ 60 6 2.73 ± 0.36 2.34–3.11 2.76 ± 0.44 2.29–3.23 Table 5 Kidney Volume (cm³) Across Age Groups Overall, these results show that the size of the kidneys and the density of the glomeruli are highest in young adults (20–39 years) and go smaller as people get older. There are statistically significant differences across age groups (p < 0.05 to p < 0.001). This shows that changes in the shape of the kidneys that happen with age. Age Group Age Range N Left Kidney Volume (Mean ± SD) 95% CI Left Kidney (cm³) Right Kidney Volume (Mean ± SD) 95% CI Right Kidney (cm³) A 10–19 9 58.07 ± 17.53 51.40–64.74 55.04 ± 6.63 49.93–60.14 B 20–39 29 58.18 ± 9.35 50.99–65.37 57.67 ± 17.86 50.88–64.47 C 40–59 6 58.17 ± 19.46 37.75–78.60 53.56 ± 20.43 28.19–78.93 D ≥ 60 6 47.72 ± 3.20 33.85–61.58 50.73 ± 8.16 42.17–59.29 Table 6 Number of Glomeruli per mm² in Kidneys Across Age Groups Age Group Age Range N Left Kidney Glomeruli (Mean ± SD) 95% CI Left Kidney Right Kidney Glomeruli (Mean ± SD) 95% CI Right Kidney A 10–19 5 8.48 ± 0.18 8.24–8.71 8.35 ± 0.20 8.10–8.61 B 20–39 5 9.33 ± 0.46 9.00–9.66 9.27 ± 0.44 8.95–9.59 C 40–59 5 8.20 ± 0.39 7.71–8.68 8.27 ± 0.42 7.74–8.79 D ≥ 60 5 7.85 ± 0.15 7.69–8.00 7.78 ± 0.19 7.57–7.98 Discussion The goal of this cadaveric study was to look into how the structure and function of human kidneys vary with age, focusing on glomerular number and diameter, tubular atrophy, interstitial fibrosis, and changes in blood vessels. The results back up earlier studies that showed that the kidneys get a lot worse over time, even when there are no obvious signs of kidney disease. Compared to younger groups, kidneys from people aged 60 and older (Group D) had a lot fewer glomeruli per mm² and larger glomeruli, which is what happens when nephron loss causes compensatory hypertrophy. The results are similar to those of Zhao et al., who used sophisticated imaging to see how the structures of healthy human organs, such kidneys, change as people get older. They found that cells become less complicated and tissues become less stable [ 8 ]. Rossiello et al. also stressed telomere dysfunction and cellular senescence as key factors in the decrease of organs with age, including the kidneys. This is in keeping with the histological evidence of impaired regeneration ability seen in this work [ 11 ]. In addition, Walsh et al. used phase-contrast CT to show that the microarchitecture of aging human kidneys is quite disorganized, especially in the cortical and vascular compartments [ 15 ]. The glomerular hypertrophy found in older people is similar to what happens in other organs as they age: cells become stressed or die, causing the structure to grow to make up for it. For example, Davies et al. [ 9 ] described alterations in the shape of microglia in the brain. In the same way, Miao et al. showed that Wnt/β-catenin signaling and problems with mitochondria are very important in renal fibrosis as people become older. These mechanisms are probably what caused the interstitial fibrosis shown in the oldest group in our study [ 16 ]. CKD is still a major public health problem around the world, affecting about 10% of people and disproportionately affecting older adults [ 14 ]. More than 30% of people over the age of 70 in Western countries and Europe have kidney problems, which is the same as the structural damage shown here [ 10 , 13 ]. In South Asia, particularly Bangladesh, the number of people with CKD is rising since the population is getting older and more people are getting diabetes and high blood pressure. There isn't much histomorphological data from this area, thus this cadaveric study is a useful addition to our knowledge of how kidneys age in different populations [ 14 , 17 ]. This study gives direct human histology data, which is different from animal models of kidney aging as those talked about by Stenvinkel et al. and Cohen et al. [ 17 , 18 ]. This means that there is no variability between species. Also, using cadaveric samples avoids confounding factors like treatment effects, as Jespersen et al. pointed out, because physiological differences in human renal tissue are not usually shown in live research [ 19 ]. The Western diet, which is heavy in advanced glycation end-products (AGEs), has been associated to faster kidney deterioration and could cause histological abnormalities to happen earlier, similar to what was reported in older cadaveric samples in this investigation [ 14 ]. These changes in the environment are especially worrisome in South Asian areas that are quickly becoming cities, where lifestyles are changing to look more like those in the West. This work adds new histomorphological evidence from a South Asian context to what we already know about how the kidneys age. The clear drop in the number of glomeruli, glomerular hypertrophy, and interstitial fibrosis that happens with age shows how important it is to find and stop problems early in older people. These results are especially important for places like Bangladesh, where there aren't many diagnostic tools and kidney illness typically goes undiagnosed until it's too late. Conclusion The study of dead bodies shows that human kidneys change a lot with age. For example, the number of glomeruli goes down, the size of the glomeruli increases, fibrosis in the interstitial space occurs, and the blood vessels get thicker. These changes in structure, which become more obvious after age 60, are linked to global trends of diminishing kidney function in older people. The results show how important it is to be able to tell typical changes that happen with aging from abnormal ones. This study gives important baseline information about the South Asian population, especially Bangladesh, where there isn't much research like this. To improve early identification and treatment of age-related kidney problems in places with few resources, it is important to understand these changes. Declarations Conflict of interest: No Funding: Self-funding IRB- SCMST/DPT/IRB-20/03-005 Author Contributions: Dr.Ashrafi Akter Zahan GROUP 1: Conception of the work, Acquisition and Analysis of data GROUP 2: Revising the work critically for important intellectual content GROUP 3: Final approval of the version to be published GROUP 4: Agree to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved Dr.Farida Yesmin GROUP 1: Design of the work, Analysis and Interpretation of data GROUP 2: Revising the work critically for important intellectual content GROUP 3: Final approval of the version to be published GROUP 4: Agree to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved Dr. Shakil Mahmood GROUP 1: Analysis of data GROUP 2: Revising the work critically for important intellectual content GROUP 3: Final approval of the version to be published. Dr. Shutopa Islam Akhi GROUP 1: Analysis and Interpretation of data GROUP 2: Revising the work critically for important intellectual content GROUP 3: Agree to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. Dr. Mohammad Fokhruzzaman GROUP 1: Interpretation of data GROUP 2: Revising the work critically for important intellectual content GROUP 3: Final approval of the version to be published Rubaya Sultana GROUP 1: Design of the work GROUP 2: Revising the work critically for important intellectual content GROUP 3: Final approval of the version to be published Jannatul Taslima Meem GROUP 1: Design of the work GROUP 2: Revising the work critically for important intellectual content GROUP 3: Agree to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. Zannatul Mawa GROUP 1: Interpretation of data GROUP 2: Revising the work critically for important intellectual content GROUP 3: Final approval of the version to be published Shahid Afridi GROUP 1: Analysis and Interpretation of data GROUP 2: Revising the work critically for important intellectual content GROUP 3: Agree to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. References Kotob MH, Hussein A, Abd-Elkareem M. Histopathological changes of kidney tissue during aging. SVU-International J Veterinary Sci. 2021;4(1):54–65. Hommos MS, Glassock RJ, Rule AD. Structural and functional changes in human kidneys with healthy aging. J Am Soc Nephrol. 2017;28(10):2838–44. Denic A, Lieske JC, Chakkera HA, Poggio ED, Alexander MP, Singh P, Kremers WK, Lerman LO, Rule AD. The substantial loss of nephrons in healthy human kidneys with aging. 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Wnt/β-catenin/RAS signaling mediates age‐related renal fibrosis and is associated with mitochondrial dysfunction. Aging Cell. 2019;18(5):e13004. Stenvinkel P, Painer J, Kuro-o M, Lanaspa M, Arnold W, Ruf T, Shiels PG, Johnson RJ. Novel treatment strategies for chronic kidney disease: insights from the animal kingdom. Nat Rev Nephrol. 2018;14(4):265–84. Cohen EP, Hankey KG, Bennett AW, Farese AM, Parker GA, MacVittie TJ. Acute and chronic kidney injury in a non-human primate model of partial-body irradiation with bone marrow sparing. Radiat Res. 2017;188(6):741–51. Jespersen NZ, Feizi A, Andersen ES, Heywood S, Hattel HB, Daugaard S, Peijs L, Bagi P, Feldt-Rasmussen B, Schultz HS, Hansen NS. Heterogeneity in the perirenal region of humans suggests presence of dormant brown adipose tissue that contains brown fat precursor cells. Mol Metabolism. 2019;24:30–43. Additional Declarations No competing interests reported. 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10:08:19","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-7317473/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-7317473/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":88872642,"identity":"848b82a3-7876-4a3e-a611-925b9f445c22","added_by":"auto","created_at":"2025-08-12 09:30:34","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":27934,"visible":true,"origin":"","legend":"\u003cp\u003eUnnumbered image in the Result section.\u003c/p\u003e","description":"","filename":"floatimage1.png","url":"https://assets-eu.researchsquare.com/files/rs-7317473/v1/2fcf647554038db7262e5ca4.png"},{"id":90007477,"identity":"cadb4cfb-7af0-4252-9d3d-567683d0d72b","added_by":"auto","created_at":"2025-08-27 09:47:48","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1049717,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7317473/v1/10c1d37f-ab20-450e-a631-8333c4e55f8a.pdf"},{"id":88872645,"identity":"82bb2469-e07e-4ac6-977b-869b442e074c","added_by":"auto","created_at":"2025-08-12 09:30:34","extension":"docx","order_by":0,"title":"","display":"","copyAsset":false,"role":"supplement","size":44035,"visible":true,"origin":"","legend":"","description":"","filename":"Suppimentoryfile.docx","url":"https://assets-eu.researchsquare.com/files/rs-7317473/v1/82e733b2318942fe881c1922.docx"}],"financialInterests":"No competing interests reported.","formattedTitle":"Age-Related Histomorphological Changes in Human Kidneys: A Cadaveric Study","fulltext":[{"header":"Background","content":"\u003cp\u003eThe human kidney is a critical organ that keeps the body in balance by filtering, reabsorbing, and secreting things [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. As we get older, the structure and function of the kidney change a lot. As people become older, their kidneys go through a lot of structural and functional changes that can affect how the kidneys work as a whole and make them more likely to develop kidney-related diseases [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e, \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. Changes in the kidneys that happen with age include glomerulosclerosis, tubular atrophy, interstitial fibrosis, and thickening of the blood vessels [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. All of these changes lead to a reduction in kidney function [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. These changes are very important for doctors because they affect how often and how many people get chronic kidney disease (CKD) and end-stage renal disease (ESRD) around the world, especially in older people [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eAbout 10% of people throughout the world have CKD. Older folks are more likely to have it because they lose nephrons and their kidneys don't work as well as they used to [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. In Western countries and Europe, the risk of CKD goes up a lot after age 60[\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. Almost 30% of people over 70 have some kind of kidney problem [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. On the other hand, South Asia, which includes Bangladesh, has a double burden of communicable and non-communicable illnesses. The number of people with CKD is rising because the population is becoming older, and more people are getting diabetes and high blood pressure [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e, \u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. There isn't enough histomorphological data on how kidneys age in these people that is specific to the area, which shows how much more research has to be done [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e, \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. The main reason why kidney function gets worse as people get older is because they lose nephrons. Studies reveal that by the eighth decade of life, the number of nephrons is cut in half [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. Histopathological tests show that renal aging is characterized by glomerular hypertrophy, increased mesangial matrix deposition, and arteriolar hyalinization [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. Thickening of the tubular basement membrane and interstitial fibrosis make functional decline worse, making people more likely to get acute kidney injury (AKI) and chronic kidney disease (CKD) [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e, \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]. Systemic disorders that are common in older people, such as hypertension and atherosclerosis, make these structural problems worse [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eThere has been a lot of research on how kidneys age in Western populations, but there is still not much data from low- and middle-income countries (LMICs), such as Bangladesh and South Asia [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e, \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]. Differences in genetics, the environment, and access to healthcare may all play a role in the different ways that different ethnic groups' kidneys age [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. Cadaveric studies are a one-of-a-kind way to look at histomorphological changes without the effects of treatment, which helps us understand how aging happens on its own [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. This study looks at how the histomorphology of human kidneys changes with age by looking at cadavers. It focuses on changes in the glomeruli, tubules, blood vessels, and interstitial tissue [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. This study will help us learn more about how kidneys age in different groups of people, especially areas that haven't been researched much before, like South Asia [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. The results may help find and treat age-related kidney problems early, especially in places with few resources. This work is necessary since kidney illness is becoming more common around the world and we need more detailed histopathology data to help with clinical management and public health measures. Finding out what causes renal aging on a structural level could help create targeted treatments to slow down functional decline in at-risk groups.\u003c/p\u003e"},{"header":"Methodology","content":"\u003cp\u003eThe current study was a descriptive cross-sectional analysis that took place in the Department of Anatomy, Rajshahi Medical College, from July 2024 to June 2025. It used 100 human kidneys that had been taken from unclaimed deceased bodies at the Dhaka Medical College morgue. We looked examined the right and left kidneys of both male and female cadavers. Specimens with birth defects, injuries, kidney disease, or decomposition were not included. There were four groups of kidneys based on age: A (10\u0026ndash;19 years), B (20\u0026ndash;39 years), C (40\u0026ndash;59 years), and D (60 years and beyond). After they were collected, the kidneys were cleaned, labeled, fixed in 10% formalin, and prepared for both morphometric and histological investigation. Using calibrated instruments and the ellipsoid formula, we assessed morphometric parameters such kidney weight, length, breadth, thickness, and volume. Five pairs of kidneys from each group were cut up, processed, and stained with hematoxylin and eosin for histological assessment. A stage micrometer and an ocular micrometer were used to measure the number of glomeruli per square millimeter and the average diameter of glomeruli. Three fields were measured on each slide. We used SPSS version 16.0 to do statistical tests such the mean, standard deviation, ANOVA, and unpaired t-tests. Rajshahi Medical College gave the go-ahead for the study. Microscopes, dissection instruments, staining chemicals, and digital measurement equipment were some of the tools employed. Even though the methodology was thorough, there were some problems that could affect the generalizability of the results. These included unequal sample sizes among age groups, a small sample size, no examination of sex differences, and a paucity of available unclaimed cadavers. Still, the study gives us useful information about how the kidneys change with age by looking at cadavers.\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003eThis study investigated at different morphometric measurements of the left and right kidneys in four age groups: A (10\u0026ndash;19 years), B (20\u0026ndash;39 years), C (40\u0026ndash;59 years), and D (\u0026ge;\u0026thinsp;60 years). There was a big difference in kidney weights with age (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001).\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003eThe left kidney weighed 85.04\u0026thinsp;\u0026plusmn;\u0026thinsp;2.30 gm in group A, then it got heavier in group B, reaching a maximum of 98.67\u0026thinsp;\u0026plusmn;\u0026thinsp;3.95 gm. In group C, it got lighter again, to 94.75\u0026thinsp;\u0026plusmn;\u0026thinsp;0.95 gm, and in group D, it was even lighter, to 85.33\u0026thinsp;\u0026plusmn;\u0026thinsp;2.48 gm.\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eKidney Weights (gm) Across Different Age Groups\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"7\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAge Group\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eAge Range\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eN\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eLeft Kidney Mean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD (gm)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003eLeft Kidney 95% CI (gm)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003eRight Kidney Mean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD (gm)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c7\"\u003e\u003cp\u003eRight Kidney 95% CI (gm)\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eA\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e10\u0026ndash;19\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e\u003cp\u003e85.04\u0026thinsp;\u0026plusmn;\u0026thinsp;2.30\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e83.27\u0026ndash;86.81\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c6\"\u003e\u003cp\u003e84.88\u0026thinsp;\u0026plusmn;\u0026thinsp;2.03\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e83.32\u0026ndash;86.45\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eB\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e20\u0026ndash;39\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e29\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e\u003cp\u003e\u003cb\u003e98.67\u0026thinsp;\u0026plusmn;\u0026thinsp;3.95\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e97.17\u0026ndash;100.17\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c6\"\u003e\u003cp\u003e\u003cb\u003e95.80\u0026thinsp;\u0026plusmn;\u0026thinsp;7.05\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e89.31\u0026ndash;102.29\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eC\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e40\u0026ndash;59\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e\u003cp\u003e94.75\u0026thinsp;\u0026plusmn;\u0026thinsp;0.95\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e93.76\u0026ndash;95.75\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c6\"\u003e\u003cp\u003e94.84\u0026thinsp;\u0026plusmn;\u0026thinsp;1.47\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e93.28\u0026ndash;96.39\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eD\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u0026ge;\u0026thinsp;60\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e\u003cp\u003e85.33\u0026thinsp;\u0026plusmn;\u0026thinsp;2.48\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e82.72\u0026ndash;87.95\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c6\"\u003e\u003cp\u003e85.19\u0026thinsp;\u0026plusmn;\u0026thinsp;2.64\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e82.41\u0026ndash;87.97\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"No\" id=\"Taba\" border=\"1\"\u003e\u003ccolgroup cols=\"4\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eKidney\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eF-value\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003ep-value\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eInterpretation\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eLeft Kidney\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e3.604\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.001\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eStatistically significant difference (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eRight Kidney\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e95.871\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.001\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eStatistically significant difference (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\n\u003cp\u003e*ANOVA Test Results\u003c/p\u003e\n\u003cp\u003eThe weight of the right kidney was the same: it was 84.88\u0026thinsp;\u0026plusmn;\u0026thinsp;2.03 gm in group A, 95.80\u0026thinsp;\u0026plusmn;\u0026thinsp;7.05 gm in group B, and 85.19\u0026thinsp;\u0026plusmn;\u0026thinsp;2.64 gm in group D. The lengths of the kidneys followed a similar pattern: in group A, the left kidney was 8.44\u0026thinsp;\u0026plusmn;\u0026thinsp;0.87 cm long, in group B it was 9.56\u0026thinsp;\u0026plusmn;\u0026thinsp;0.98 cm long, and in groups C (8.55\u0026thinsp;\u0026plusmn;\u0026thinsp;0.50 cm) and D (8.42\u0026thinsp;\u0026plusmn;\u0026thinsp;0.27 cm) it got shorter. The length of the right kidney was similar, ranging from 8.45\u0026thinsp;\u0026plusmn;\u0026thinsp;0.40 cm in group A to 9.41\u0026thinsp;\u0026plusmn;\u0026thinsp;1.03 cm in group B and lower values in older groups.\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003e\u003cb\u003eKidney Lengths (cm) Across Different Age Groups\u003c/b\u003e The left kidney in group B was the widest, measuring 4.16\u0026thinsp;\u0026plusmn;\u0026thinsp;0.44 cm, while the right kidney was the widest, measuring 3.95\u0026thinsp;\u0026plusmn;\u0026thinsp;0.57 cm. Group D had the narrowest breadth, with the left kidney measuring 3.88\u0026thinsp;\u0026plusmn;\u0026thinsp;0.62 cm and the right kidney measuring 3.65\u0026thinsp;\u0026plusmn;\u0026thinsp;0.34 cm. The same trend held true for thickness measurements: the left kidney was 3.28\u0026thinsp;\u0026plusmn;\u0026thinsp;0.40 cm thick in group B and 2.73\u0026thinsp;\u0026plusmn;\u0026thinsp;0.36 cm thick in group D, and the right kidney was 3.27\u0026thinsp;\u0026plusmn;\u0026thinsp;0.30 cm thick in group B and 2.76\u0026thinsp;\u0026plusmn;\u0026thinsp;0.44 cm thick in group D.\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"7\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAge Group\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eAge Range\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eN\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eLeft Kidney Mean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD (cm)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003eLeft Kidney 95% CI (cm)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003eRight Kidney Mean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD (cm)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c7\"\u003e\u003cp\u003eRight Kidney 95% CI (cm)\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eA\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e10\u0026ndash;19\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e\u003cp\u003e8.44\u0026thinsp;\u0026plusmn;\u0026thinsp;0.87\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e8.11\u0026ndash;8.78\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c6\"\u003e\u003cp\u003e8.45\u0026thinsp;\u0026plusmn;\u0026thinsp;0.40\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e8.14\u0026ndash;8.76\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eB\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e20\u0026ndash;39\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e29\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e\u003cp\u003e\u003cb\u003e9.56\u0026thinsp;\u0026plusmn;\u0026thinsp;0.98\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e8.63\u0026ndash;9.70\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c6\"\u003e\u003cp\u003e\u003cb\u003e9.41\u0026thinsp;\u0026plusmn;\u0026thinsp;1.03\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e8.33\u0026ndash;9.50\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eC\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e40\u0026ndash;59\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e\u003cp\u003e8.55\u0026thinsp;\u0026plusmn;\u0026thinsp;0.50\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e8.01\u0026ndash;9.08\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c6\"\u003e\u003cp\u003e8.70\u0026thinsp;\u0026plusmn;\u0026thinsp;0.40\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e8.27\u0026ndash;9.12\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eD\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u0026ge;\u0026thinsp;60\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e\u003cp\u003e8.42\u0026thinsp;\u0026plusmn;\u0026thinsp;0.27\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e8.21\u0026ndash;8.63\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c6\"\u003e\u003cp\u003e8.38\u0026thinsp;\u0026plusmn;\u0026thinsp;1.08\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e7.96\u0026ndash;8.79\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003e\u003cb\u003eKidney Breadth (cm) Across Different Age Groups\u003c/b\u003e Group B had the most kidney volume, with the left kidney measuring 58.18\u0026thinsp;\u0026plusmn;\u0026thinsp;9.35 cm\u0026sup3; and the right kidney measuring 57.67\u0026thinsp;\u0026plusmn;\u0026thinsp;17.86 cm\u0026sup3;. The volumes for Group D were the smallest: 47.72\u0026thinsp;\u0026plusmn;\u0026thinsp;3.20 cm\u0026sup3; on the left and 50.73\u0026thinsp;\u0026plusmn;\u0026thinsp;8.16 cm\u0026sup3; on the right.\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"7\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAge Group\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eAge Range\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eN\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eLeft Kidney Breadth\u0026thinsp;\u0026lt;\u0026thinsp;br\u0026thinsp;\u0026gt;\u0026thinsp;Mean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD (cm)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003e95% CI Left Kidney (cm)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003eRight Kidney Breadth\u0026thinsp;\u0026lt;\u0026thinsp;br\u0026thinsp;\u0026gt;\u0026thinsp;Mean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD (cm)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c7\"\u003e\u003cp\u003e95% CI Right Kidney (cm)\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eA\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e10\u0026ndash;19\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e\u003cp\u003e4.06\u0026thinsp;\u0026plusmn;\u0026thinsp;0.37\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e3.77\u0026ndash;4.35\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c6\"\u003e\u003cp\u003e3.82\u0026thinsp;\u0026plusmn;\u0026thinsp;0.28\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e3.60\u0026ndash;4.04\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eB\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e20\u0026ndash;39\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e29\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e\u003cp\u003e\u003cb\u003e4.16\u0026thinsp;\u0026plusmn;\u0026thinsp;0.44\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e3.99\u0026ndash;4.33\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c6\"\u003e\u003cp\u003e\u003cb\u003e3.95\u0026thinsp;\u0026plusmn;\u0026thinsp;0.57\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e3.73\u0026ndash;4.16\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eC\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e40\u0026ndash;59\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e\u003cp\u003e4.05\u0026thinsp;\u0026plusmn;\u0026thinsp;0.36\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e3.66\u0026ndash;4.43\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c6\"\u003e\u003cp\u003e3.76\u0026thinsp;\u0026plusmn;\u0026thinsp;0.21\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e3.54\u0026ndash;3.99\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eD\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u0026ge;\u0026thinsp;60\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e\u003cp\u003e3.88\u0026thinsp;\u0026plusmn;\u0026thinsp;0.62\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e3.22\u0026ndash;4.53\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c6\"\u003e\u003cp\u003e3.65\u0026thinsp;\u0026plusmn;\u0026thinsp;0.34\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e3.50\u0026ndash;3.80\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab4\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 4\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003e\u003cb\u003eKidney Thickness (cm) Across Different Age Groups\u003c/b\u003e Finally, group B had the most glomeruli per mm\u0026sup2;, with 9.33\u0026thinsp;\u0026plusmn;\u0026thinsp;0.46 in the left kidney and 9.27\u0026thinsp;\u0026plusmn;\u0026thinsp;0.44 in the right kidney. The number of glomeruli per mm\u0026sup2; went down in older groups.\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"7\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAge Group\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eAge Range\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eN\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eLeft Kidney Thickness\u0026thinsp;\u0026lt;\u0026thinsp;br\u0026thinsp;\u0026gt;\u0026thinsp;Mean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD (cm)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003e95% CI Left Kidney (cm)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003eRight Kidney Thickness\u0026thinsp;\u0026lt;\u0026thinsp;br\u0026thinsp;\u0026gt;\u0026thinsp;Mean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD (cm)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c7\"\u003e\u003cp\u003e95% CI Right Kidney (cm)\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eA\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e10\u0026ndash;19\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e\u003cp\u003e3.04\u0026thinsp;\u0026plusmn;\u0026thinsp;0.46\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e2.86\u0026ndash;3.21\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c6\"\u003e\u003cp\u003e3.02\u0026thinsp;\u0026plusmn;\u0026thinsp;0.36\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e2.66\u0026ndash;3.20\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eB\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e20\u0026ndash;39\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e29\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e\u003cp\u003e\u003cb\u003e3.28\u0026thinsp;\u0026plusmn;\u0026thinsp;0.40\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e2.98\u0026ndash;3.59\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c6\"\u003e\u003cp\u003e\u003cb\u003e3.27\u0026thinsp;\u0026plusmn;\u0026thinsp;0.30\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e3.04\u0026ndash;3.51\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eC\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e40\u0026ndash;59\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e\u003cp\u003e3.07\u0026thinsp;\u0026plusmn;\u0026thinsp;0.16\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e2.60\u0026ndash;3.50\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c6\"\u003e\u003cp\u003e3.06\u0026thinsp;\u0026plusmn;\u0026thinsp;0.58\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e2.45\u0026ndash;3.68\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eD\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u0026ge;\u0026thinsp;60\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e\u003cp\u003e2.73\u0026thinsp;\u0026plusmn;\u0026thinsp;0.36\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e2.34\u0026ndash;3.11\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c6\"\u003e\u003cp\u003e2.76\u0026thinsp;\u0026plusmn;\u0026thinsp;0.44\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e2.29\u0026ndash;3.23\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab5\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 5\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003e\u003cb\u003eKidney Volume (cm\u0026sup3;) Across Age Groups\u003c/b\u003e Overall, these results show that the size of the kidneys and the density of the glomeruli are highest in young adults (20\u0026ndash;39 years) and go smaller as people get older. There are statistically significant differences across age groups (p\u0026thinsp;\u0026lt;\u0026thinsp;0.05 to p\u0026thinsp;\u0026lt;\u0026thinsp;0.001). This shows that changes in the shape of the kidneys that happen with age.\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"7\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAge Group\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eAge Range\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eN\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eLeft Kidney Volume (Mean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003e95% CI Left Kidney (cm\u0026sup3;)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003eRight Kidney Volume (Mean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c7\"\u003e\u003cp\u003e95% CI Right Kidney (cm\u0026sup3;)\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eA\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e10\u0026ndash;19\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e\u003cp\u003e58.07\u0026thinsp;\u0026plusmn;\u0026thinsp;17.53\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e51.40\u0026ndash;64.74\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c6\"\u003e\u003cp\u003e55.04\u0026thinsp;\u0026plusmn;\u0026thinsp;6.63\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e49.93\u0026ndash;60.14\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eB\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e20\u0026ndash;39\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e29\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e\u003cp\u003e58.18\u0026thinsp;\u0026plusmn;\u0026thinsp;9.35\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e50.99\u0026ndash;65.37\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c6\"\u003e\u003cp\u003e57.67\u0026thinsp;\u0026plusmn;\u0026thinsp;17.86\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e50.88\u0026ndash;64.47\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eC\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e40\u0026ndash;59\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e\u003cp\u003e58.17\u0026thinsp;\u0026plusmn;\u0026thinsp;19.46\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e37.75\u0026ndash;78.60\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c6\"\u003e\u003cp\u003e53.56\u0026thinsp;\u0026plusmn;\u0026thinsp;20.43\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e28.19\u0026ndash;78.93\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eD\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u0026ge;\u0026thinsp;60\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e\u003cp\u003e47.72\u0026thinsp;\u0026plusmn;\u0026thinsp;3.20\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e33.85\u0026ndash;61.58\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c6\"\u003e\u003cp\u003e50.73\u0026thinsp;\u0026plusmn;\u0026thinsp;8.16\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e42.17\u0026ndash;59.29\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab6\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 6\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eNumber of Glomeruli per mm\u0026sup2; in Kidneys Across Age Groups\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"7\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAge Group\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eAge Range\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eN\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eLeft Kidney Glomeruli (Mean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003e95% CI Left Kidney\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003eRight Kidney Glomeruli (Mean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c7\"\u003e\u003cp\u003e95% CI Right Kidney\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eA\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e10\u0026ndash;19\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e\u003cp\u003e8.48\u0026thinsp;\u0026plusmn;\u0026thinsp;0.18\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e8.24\u0026ndash;8.71\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c6\"\u003e\u003cp\u003e8.35\u0026thinsp;\u0026plusmn;\u0026thinsp;0.20\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e8.10\u0026ndash;8.61\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eB\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e20\u0026ndash;39\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e\u003cp\u003e\u003cb\u003e9.33\u0026thinsp;\u0026plusmn;\u0026thinsp;0.46\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e9.00\u0026ndash;9.66\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c6\"\u003e\u003cp\u003e\u003cb\u003e9.27\u0026thinsp;\u0026plusmn;\u0026thinsp;0.44\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e8.95\u0026ndash;9.59\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eC\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e40\u0026ndash;59\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e\u003cp\u003e8.20\u0026thinsp;\u0026plusmn;\u0026thinsp;0.39\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e7.71\u0026ndash;8.68\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c6\"\u003e\u003cp\u003e8.27\u0026thinsp;\u0026plusmn;\u0026thinsp;0.42\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e7.74\u0026ndash;8.79\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eD\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u0026ge;\u0026thinsp;60\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e\u003cp\u003e7.85\u0026thinsp;\u0026plusmn;\u0026thinsp;0.15\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e7.69\u0026ndash;8.00\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c6\"\u003e\u003cp\u003e7.78\u0026thinsp;\u0026plusmn;\u0026thinsp;0.19\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e7.57\u0026ndash;7.98\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eThe goal of this cadaveric study was to look into how the structure and function of human kidneys vary with age, focusing on glomerular number and diameter, tubular atrophy, interstitial fibrosis, and changes in blood vessels. The results back up earlier studies that showed that the kidneys get a lot worse over time, even when there are no obvious signs of kidney disease. Compared to younger groups, kidneys from people aged 60 and older (Group D) had a lot fewer glomeruli per mm\u0026sup2; and larger glomeruli, which is what happens when nephron loss causes compensatory hypertrophy. The results are similar to those of Zhao et al., who used sophisticated imaging to see how the structures of healthy human organs, such kidneys, change as people get older. They found that cells become less complicated and tissues become less stable [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. Rossiello et al. also stressed telomere dysfunction and cellular senescence as key factors in the decrease of organs with age, including the kidneys. This is in keeping with the histological evidence of impaired regeneration ability seen in this work [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. In addition, Walsh et al. used phase-contrast CT to show that the microarchitecture of aging human kidneys is quite disorganized, especially in the cortical and vascular compartments [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eThe glomerular hypertrophy found in older people is similar to what happens in other organs as they age: cells become stressed or die, causing the structure to grow to make up for it. For example, Davies et al. [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e] described alterations in the shape of microglia in the brain. In the same way, Miao et al. showed that Wnt/β-catenin signaling and problems with mitochondria are very important in renal fibrosis as people become older. These mechanisms are probably what caused the interstitial fibrosis shown in the oldest group in our study [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]. CKD is still a major public health problem around the world, affecting about 10% of people and disproportionately affecting older adults [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]. More than 30% of people over the age of 70 in Western countries and Europe have kidney problems, which is the same as the structural damage shown here [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e, \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. In South Asia, particularly Bangladesh, the number of people with CKD is rising since the population is getting older and more people are getting diabetes and high blood pressure. There isn't much histomorphological data from this area, thus this cadaveric study is a useful addition to our knowledge of how kidneys age in different populations [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e, \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]. This study gives direct human histology data, which is different from animal models of kidney aging as those talked about by Stenvinkel et al. and Cohen et al. [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e, \u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]. This means that there is no variability between species. Also, using cadaveric samples avoids confounding factors like treatment effects, as Jespersen et al. pointed out, because physiological differences in human renal tissue are not usually shown in live research [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eThe Western diet, which is heavy in advanced glycation end-products (AGEs), has been associated to faster kidney deterioration and could cause histological abnormalities to happen earlier, similar to what was reported in older cadaveric samples in this investigation [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]. These changes in the environment are especially worrisome in South Asian areas that are quickly becoming cities, where lifestyles are changing to look more like those in the West. This work adds new histomorphological evidence from a South Asian context to what we already know about how the kidneys age. The clear drop in the number of glomeruli, glomerular hypertrophy, and interstitial fibrosis that happens with age shows how important it is to find and stop problems early in older people. These results are especially important for places like Bangladesh, where there aren't many diagnostic tools and kidney illness typically goes undiagnosed until it's too late.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eThe study of dead bodies shows that human kidneys change a lot with age. For example, the number of glomeruli goes down, the size of the glomeruli increases, fibrosis in the interstitial space occurs, and the blood vessels get thicker. These changes in structure, which become more obvious after age 60, are linked to global trends of diminishing kidney function in older people. The results show how important it is to be able to tell typical changes that happen with aging from abnormal ones. This study gives important baseline information about the South Asian population, especially Bangladesh, where there isn't much research like this. To improve early identification and treatment of age-related kidney problems in places with few resources, it is important to understand these changes.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eConflict of interest:\u003c/strong\u003e No\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding:\u003c/strong\u003e Self-funding\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eIRB-\u003c/strong\u003e\u003cem\u003eSCMST/DPT/IRB-20/03-005\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor Contributions:\u003c/strong\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eDr.Ashrafi Akter Zahan\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eGROUP 1: Conception of the work, Acquisition and Analysis of data\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eGROUP 2: Revising the work critically for important intellectual content\u003c/p\u003e\n\u003cp\u003eGROUP 3: Final approval of the version to be published\u003c/p\u003e\n\u003cp\u003eGROUP 4: Agree to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eDr.Farida Yesmin\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eGROUP 1: Design of the work, Analysis and Interpretation of data\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eGROUP 2: Revising the work critically for important intellectual content\u003c/p\u003e\n\u003cp\u003eGROUP 3: Final approval of the version to be published\u003c/p\u003e\n\u003cp\u003eGROUP 4: Agree to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eDr. Shakil Mahmood\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eGROUP 1: Analysis of data\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eGROUP 2: Revising the work critically for important intellectual content\u003c/p\u003e\n\u003cp\u003eGROUP 3: Final approval of the version to be published.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eDr. Shutopa Islam Akhi\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eGROUP 1: Analysis and Interpretation of data\u003c/p\u003e\n\u003cp\u003eGROUP 2: Revising the work critically for important intellectual content\u003c/p\u003e\n\u003cp\u003eGROUP 3: Agree to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eDr. Mohammad Fokhruzzaman\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eGROUP 1: Interpretation of data\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eGROUP 2: Revising the work critically for important intellectual content\u003c/p\u003e\n\u003cp\u003eGROUP 3: Final approval of the version to be published\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eRubaya Sultana\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eGROUP 1: Design of the work\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eGROUP 2: Revising the work critically for important intellectual content\u003c/p\u003e\n\u003cp\u003eGROUP 3: Final approval of the version to be published\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eJannatul Taslima Meem\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eGROUP 1: Design of the work\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eGROUP 2: Revising the work critically for important intellectual content\u003c/p\u003e\n\u003cp\u003eGROUP 3: Agree to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eZannatul Mawa\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eGROUP 1: Interpretation of data\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eGROUP 2: Revising the work critically for important intellectual content\u003c/p\u003e\n\u003cp\u003eGROUP 3: Final approval of the version to be published\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eShahid Afridi\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eGROUP 1: Analysis and Interpretation of data\u003c/p\u003e\n\u003cp\u003eGROUP 2: Revising the work critically for important intellectual content\u003c/p\u003e\n\u003cp\u003eGROUP 3: Agree to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eKotob MH, Hussein A, Abd-Elkareem M. Histopathological changes of kidney tissue during aging. SVU-International J Veterinary Sci. 2021;4(1):54\u0026ndash;65.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eHommos MS, Glassock RJ, Rule AD. Structural and functional changes in human kidneys with healthy aging. J Am Soc Nephrol. 2017;28(10):2838\u0026ndash;44.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eDenic A, Lieske JC, Chakkera HA, Poggio ED, Alexander MP, Singh P, Kremers WK, Lerman LO, Rule AD. The substantial loss of nephrons in healthy human kidneys with aging. J Am Soc Nephrol. 2017;28(1):313\u0026ndash;20.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eAslan A, van den Heuvel MC, Stegeman CA, Popa ER, Leliveld AM, Molema G, Zijlstra JG, Moser J, van Meurs M. Kidney histopathology in lethal human sepsis. Crit Care. 2018;22(1):359.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eRyan D, Sutherland MR, Flores TJ, Kent AL, Dahlstrom JE, Puelles VG, Bertram JF, McMahon AP, Little MH, Moore L, Black MJ. Development of the human fetal kidney from mid to late gestation in male and female infants. EBioMedicine. 2018;27:275\u0026ndash;83.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eKomutrattananont P, Mahakkanukrauh P, Das S. Morphology of the human aorta and age-related changes: anatomical facts. Anat cell biology. 2019;52(2):109\u0026ndash;14.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eJingushi K, Uemura M, Ohnishi N, Nakata W, Fujita K, Naito T, Fujii R, Saichi N, Nonomura N, Tsujikawa K, Ueda K. Extracellular vesicles isolated from human renal cell carcinoma tissues disrupt vascular endothelial cell morphology via azurocidin. Int J Cancer. 2018;142(3):607\u0026ndash;17.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eZhao S, Todorov MI, Cai R, Ai-Maskari R, Steinke H, Kemter E, Mai H, Rong Z, Warmer M, Stanic K, Schoppe O. Cellular and molecular probing of intact human organs. Cell. 2020;180(4):796\u0026ndash;812.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eDavies DS, Ma J, Jegathees T, Goldsbury C. Microglia show altered morphology and reduced arborization in human brain during aging and A lzheimer's disease. Brain Pathol. 2017;27(6):795\u0026ndash;808.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eLowe JS, Anderson PG, Anderson SI. Stevens \u0026amp; Lowe's Human Histology-E-Book: Stevens \u0026amp; Lowe's Human Histology-E-Book. Elsevier Health Sciences; 2023. Dec 13.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eRossiello F, Jurk D, Passos JF. d\u0026rsquo;Adda di Fagagna F. Telomere dysfunction in ageing and age-related diseases. Nat Cell Biol. 2022;24(2):135\u0026ndash;47.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eAlfaras I, Mitchell SJ, Mora H, Lugo DR, Warren A, Navas-Enamorado I, Hoffmann V, Hine C, Mitchell JR, Le Couteur DG, Cogger VC. Health benefits of late-onset metformin treatment every other week in mice. NPJ aging Mech disease. 2017;3(1):16.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eSiva S, Ali M, Correa RJ, Muacevic A, Ponsky L, Ellis RJ, Lo SS, Onishi H, Swaminath A, McLaughlin M, Morgan SC. 5-year outcomes after stereotactic ablative body radiotherapy for primary renal cell carcinoma: an individual patient data meta-analysis from IROCK (the International Radiosurgery Consortium of the Kidney). Lancet Oncol. 2022;23(12):1508\u0026ndash;16.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eBettiga A, Fiorio F, Di Marco F, Trevisani F, Romani A, Porrini E, Salonia A, Montorsi F, Vago R. The modern western diet rich in advanced glycation end-products (AGEs): An overview of its impact on obesity and early progression of renal pathology. Nutrients. 2019;11(8):1748.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eWalsh CL, Tafforeau P, Wagner WL, Jafree DJ, Bellier A, Werlein C, K\u0026uuml;hnel MP, Boller E, Walker-Samuel S, Robertus JL, Long DA. Imaging intact human organs with local resolution of cellular structures using hierarchical phase-contrast tomography. Nat Methods. 2021;18(12):1532\u0026ndash;41.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eMiao J, Liu J, Niu J, Zhang Y, Shen W, Luo C, Liu Y, Li C, Li H, Yang P, Liu Y. Wnt/β-catenin/RAS signaling mediates age‐related renal fibrosis and is associated with mitochondrial dysfunction. Aging Cell. 2019;18(5):e13004.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eStenvinkel P, Painer J, Kuro-o M, Lanaspa M, Arnold W, Ruf T, Shiels PG, Johnson RJ. Novel treatment strategies for chronic kidney disease: insights from the animal kingdom. Nat Rev Nephrol. 2018;14(4):265\u0026ndash;84.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eCohen EP, Hankey KG, Bennett AW, Farese AM, Parker GA, MacVittie TJ. Acute and chronic kidney injury in a non-human primate model of partial-body irradiation with bone marrow sparing. Radiat Res. 2017;188(6):741\u0026ndash;51.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eJespersen NZ, Feizi A, Andersen ES, Heywood S, Hattel HB, Daugaard S, Peijs L, Bagi P, Feldt-Rasmussen B, Schultz HS, Hansen NS. Heterogeneity in the perirenal region of humans suggests presence of dormant brown adipose tissue that contains brown fat precursor cells. Mol Metabolism. 2019;24:30\u0026ndash;43.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Renal Aging, Kidney Morphometry, Glomeruli, Interstitial Fibrosis","lastPublishedDoi":"10.21203/rs.3.rs-7317473/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7317473/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground: \u003c/strong\u003eAs people become older, their kidneys change in both structure and function, which makes them less able to do their job and raises the risk of chronic kidney disease (CKD), especially in older people. Even though a lot of research has been done on Western cultures, there isn't much information about how kidneys age in South Asian populations, like Bangladesh.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eObjective: \u003c/strong\u003eThe goal of this study was to look at how the structure of human kidneys varies with age in different age groups using cadaver samples from Bangladesh.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethodology\u003c/strong\u003e: At Dhaka Medical College, researchers did a descriptive cross-sectional study on 100 kidneys from unclaimed bodies. The bodies were divided into four age groups: 10–19, 20–39, 40–59, and 60 years or older. We assessed morphometric characteristics such kidney weight, length, width, thickness, and volume. We also used hematoxylin and eosin staining to look at the number and size of glomeruli. ANOVA and unpaired t-tests were used to do the statistical analysis.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults: \u003c/strong\u003eThe size and volume of the kidneys were highest in the 20–39 years group and dropped a lot in older age groups (≥ 60 years). As people got older, the number of glomeruli per mm² went down, but the diameter of the glomeruli went up. This is a sign of compensatory hypertrophy. Histological results also showed that older kidneys had more interstitial fibrosis and thicker blood vessels. These findings support global patterns of kidney aging and draw attention to unique structural changes in South Asia.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusion: \u003c/strong\u003eThe work gives important baseline histomorphological information about how kidneys age in a South Asian population, showing that the structure of kidneys starts to break down after age 60. To find and treat age-related kidney disorders early, it's important to understand these changes, especially in places like Bangladesh where resources are limited.\u003c/p\u003e","manuscriptTitle":"Age-Related Histomorphological Changes in Human Kidneys: A Cadaveric Study","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-08-12 09:30:30","doi":"10.21203/rs.3.rs-7317473/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"e41c1f82-6b93-46b7-8b95-b22b7a3c1a67","owner":[],"postedDate":"August 12th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-08-27T09:39:26+00:00","versionOfRecord":[],"versionCreatedAt":"2025-08-12 09:30:30","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7317473","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7317473","identity":"rs-7317473","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}