{"paper_id":"3f344be5-c9ed-4ba5-a8d0-b23940f14abd","body_text":"Data from the Nationwide Inpatient Sample from the Agency for Healthcare\nResearch and Quality were used for the analysis. The Nationwide Inpatient Sample,\nthe largest publicly available all-payer inpatient care database in the United\nStates, contains a random sample of approximately 20% of discharges from all\nhospitals within the United States. The sampling frame for Nationwide Inpatient\nSample includes nonfederal, general, and specialty-specific hospitals throughout the\nUnited States. Sampled hospitals include both academic and community facilities. The\nNationwide Inpatient Sample included approximately 8 million hospital stays from 45\nstates in 2010. 16  Institutional\nreview board exemption was obtained from Columbia University to perform this\nstudy.\nWe analyzed women aged 18 years or older who underwent inpatient\nhysterectomy between 1998 and 2010. Patients were stratified based on the\nInternational Classification of Diseases, 9th Revision, Clinical Modification\n(ICD-9-CM) coding into five groups based on the type of hysterectomy performed:\nabdominal (68.3, 68.39, 68.4, 68.49, 68.9), vaginal (68.5, 68.59), laparoscopic\n(68.31, 68.41, 68.51), robotic (17.4× and any other code for hysterectomy),\nand radical (68.6, 68.61, 68.69, 68.7). Each procedure was further classified as a\ntotal or subtotal (supracervical) hysterectomy.\nConcomitant procedures performed at the time of hysterectomy were recorded\nbased on ICD-9-CM coding and included oophorectomy (either unilateral or bilateral),\nanterior colporrhaphy, posterior colporrhaphy, and anti-incontinence repair\nprocedures. 17 - 19  Each of the following indications for\nsurgery was examined: leiomyoma, endometriosis, abnormal bleeding, benign ovarian\nneoplasms, pelvic organ prolapse, and gynecologic cancer. Patients may have had\nmultiple indications for surgery. 17 - 19\nAge was classified as less than 40 years, 40–49 years, 50–59\nyears, 60–69 years, 70–79 years, and 80 or more years. Race was\ncategorized as white, black, Hispanic, other, and unknown. Each patient’s\nhousehold income was classified by Nationwide Inpatient Sample as low, medium, high,\nor highest. Similarly, insurance status was grouped as private, Medicare, Medicaid,\nself-pay, other, and unknown. Risk adjustment for medical comorbidities was\nperformed using the Elixhauser comorbidity index. Patients were categorized based on\nthe number of medical comorbidities into: zero, one, or two or more, as previously\nreported. 20\nThe hospitals in which patients were treated were characterized based on\nlocation (urban, rural), region of the country (northeast, midwest, west, south),\nsize (small, medium, large), and teaching status (teaching, nonteaching). Hospital\nvolume was calculated annually as the total number of hysterectomies performed\nwithin a given hospital. For each year, the numbers of patients treated at the\nhighest decile by volume and highest quartile by volume were estimated.\nNational estimates of the number of inpatient hysterectomies performed were\nobtained through weighted discharge-level estimates provided by Nationwide Inpatient\nSample. Within the Nationwide Inpatient Sample, each patient record contains a\n“discharge weight.” These weights are calculated by stratifying\nhospitals within the Nationwide Inpatient Sample based on the following\ncharacteristics: geographic region, urban or rural location, teaching status, bed\nsize, and hospital ownership. Based on this schema, a weight is obtained by dividing\nthe number of Nationwide Inpatient Sample discharges within a given hospital stratum\nby the number of discharges within that universe of hospital discharges within that\nstratum using data obtained from the American Hospital Association. When the\nresulting weight is applied, it is an estimate of all hospital discharges within the\nUnited States. 21\nFrequency distributions between categorical variables were compared using\nχ 2  tests. Trends in use of each type of hysterectomy as well\nas trends based on indication and hospital characteristics are reported\ndescriptively. Mean and median hospital volumes were compared across the years of\nstudy using analysis of variance and Kruskal-Wallis tests, respectively.\nχ 2  tests were used to examine changes in the number of\npatients treated in the top decile and top quartile by volume hospitals over the\ncourse of the study.\nIn addition to the overall analyses, a series of sensitivity analyses were\nperformed. In the sensitivity analyses, the patients who underwent hysterectomy for\nleiomyomata were selected and trends in performance based on hospital teaching\nstatus, hospital size, payer mix, and race were performed.\n P <.05 was considered statistically significant. All\nanalyses were conducted with SAS 9.13. All statistical tests were two-sided.\n\nA total of 1,507,433 women who underwent inpatient hysterectomy were\nidentified ( Table 1 ). After weighting, this\nyielded a cohort of 7,438,452 women who underwent inpatient hysterectomy between\n1998 and 2010. The total number of hysterectomies performed annually in the United\nStates rose from 543,812 in 1998 to a peak of 681,234 procedures in 2002. From 2002\nto 2010, the number of inpatient hysterectomies performed annually declined\nconsistently each year and reached 433,621 cases in 2010 ( Fig. 1 ). Overall, 247,973 (36.4%) fewer inpatient\nhysterectomies were performed in 2010 compared with 2002.\nFigure 2A  displays the route of\nhysterectomy used stratified by year of diagnosis. Abdominal hysterectomy accounted\nfor 65% of procedures in 1998, increased to a peak of 68.9% of cases\nin 2002, and then declined to 54.2% by 2010. The use of vaginal hysterectomy\ndeclined throughout, from 24.8% in 1998 to 16.7% in 2010. Use of\nlaparoscopic hysterectomy increased to a peak of 15.5% of cases in 2006 and\nthen declined to 8.6% of procedures, whereas use of robotic hysterectomy\nincreased from 2008 to 2010 (0.9–8.2%).\nIndications for hysterectomy are shown in  Figure 2B . There was a sharp decline in inpatient hysterectomy for\nleiomyoma that peaked at 373,629 procedures in 2002 and then decreased to 195,735\ncases in 2010 (−177,894 cases [−47.6%]).\nSimilarly, hysterectomy for endometriosis rapidly declined from a high of 239,844\noperations in 2002 to only 83,158 hysterectomies in 2010 (−156,686 cases\n[−65.3%]), whereas hysterectomy for benign ovarian\nmass decreased from 189,560 to 69,937 (−119,623 cases\n[−63.1%]) during the same timeframe. During the\nstudy period, hysterectomy for abnormal bleeding increased to 274,473 in 2002 and\nthen decreased to 195,231 in 2010 (−79,242 cases\n[−28.9%]). Hysterectomy for pelvic organ prolapse\ndeclined from 122,495 cases in 2002 to 74,230 procedures in 2010 (−48,265\ncases [−39.4%]). Hysterectomy for gynecologic\ncancers remained relatively stable with a slight increase from 1998 (47,018) to 2010\n(53,506).\nTable 2  displays the hospital-level\ntrends in performance of hysterectomy. The mean and median hospital case volumes\nincreased from 1998 to peak values in 2002 (mean 157.2 procedures, standard\ndeviation 201.4; median 83 procedures, interquartile range 15–219). The\naverage hospital volume then decreased over the remaining years of study to a mean\nof 101.1 cases (standard deviation 131.9) ( P <.001) and\nmedian of 50 cases (interquartile range 11–134)\n( P <.001) in 2010. Despite the decrease in mean hospital\ncase volume, the percentage of patients treated at the highest volume hospitals\nincreased over time. The percentage of patients treated at the highest decile by\nvolume hospitals increased from 39.0% in 1998 to 41.5% in 2010\n( P <.001). Similarly, 68.8% underwent surgery at\nthe highest quartile by volume hospitals in 1998 compared with 71.2% in 2010\n( P <.001).\nFigure 3  shows the use of hysterectomy\nbased on hospital and regional characteristics. In 2010, non-teaching hospitals\nperformed 83,479 fewer hysterectomies than in 1998, whereas teaching hospitals\nperformed 25,422 fewer cases ( P <.001). The percentage of\nhysterectomies performed at teaching hospitals increased from 43.2% in 1998\nto 48.3% in 2010. The number of hysterectomies performed decreased at\nhospitals regardless of size. Between 2002 and 2010, the number of hysterectomies\nperformed decreased in the northeast (−19,830 cases\n[−20.3%]), midwest (−58,634 cases\n[236.2%]), and west (−46,626\n[−33.3%]), but the greatest reduction was in the\nsouth (−122,523 [−43.5%]). In a series of\nsensitivity analyses in which the cohort was limited to just those women who\nunderwent hysterectomy for leiomyomas, our findings were largely unchanged.\n\nThese data suggest that the number of inpatient hysterectomies performed in\nthe United States has declined substantially with nearly one-fourth of a million\nfewer procedures in 2010 than 2002. There has been minimal market concentration for\nhysterectomy with a resultant decrease of more than 40% in the median number\nof procedures performed per hospital.\nA number of factors have likely contributed to the substantial decline in\nthe number of inpatient hysterectomies. Perhaps most importantly, a number of less\ninvasive alternatives to hysterectomy have diffused into practice over the past\ndecade for benign gynecologic disease. 6 - 8 , 10 , 22 - 27  Uterine artery embolization is now\nfrequently used for symptomatic uterine leiomyomas and is associated with\nsatisfaction rates similar to hysterectomy and a quicker return to normal\nactivities. 7  Similarly,\nendometrial ablation is a less invasive alternative to hysterectomy for symptomatic\nvaginal bleeding. 6 , 8 , 23 - 27  Over a relatively short period of\ntime, the number of hysterectomies performed for uterine leiomyomata and genital\ntract bleeding has dropped substantially.\nAlthough uterine-sparing surgical options have been introduced for many\ngynecologic disorders, there has also been a general trend toward more conservative,\nnonsurgical management for a number of diseases. Hormonal therapy is frequently used\nfor abnormal bleeding. 9 , 28  Increased evidence is now available for\nnumerous pharmacologic interventions for the treatment of endometriosis-related\npain, including oral contraceptives, gonadotropin-releasing hormone agonists,\ntranexamic acid, nonsteroidal anti-inflammatory drugs, progestins, androgen\nderivatives, and several alternative medicine approaches. 5 , 29 - 33  Finally, there is growing evidence\nthat many ovarian cysts are low risk for malignancy and can safely be monitored by\nultrasonography. 4 , 34\nAn important consideration in the current analysis is that the Nationwide\nInpatient Sample does not capture same-day surgery and, as a result, patients\ndischarged on the day of surgery were not included. Our findings thus represent\ninpatient hysterectomies. This likely led to some underestimation of the number of\nhysterectomies performed, particularly for laparoscopic and robotic procedures.\nNonetheless, the Nationwide Inpatient Sample represents one of the only data sources\nthat allows extrapolation of population-level procedural trends in the United States\nand provides valuable data regarding the patterns of care of women.\nAlong with the rapid decline in the rate of hysterectomy, we noted a marked\nreduction in the average hospital case volume for the procedure. Over the past\ndecade, there has been a general trend toward increasing hospital procedural volume\nfor high-risk surgical procedures. This trend has predominantly been observed for\nprocedures with a strong association between outcomes and surgical volume. 2  The hospital-level trends for\nhysterectomy have been similar to coronary artery bypass graft, also a procedure\nthat has seen a rapid decline in use over the past decade. In a report of Medicare\nbeneficiaries, Birkmeyer and colleagues 2  noted that the median hospital volume of coronary artery bypass\ngraft decreased from 244 cases in 1999–2000 to 130 procedures in\n2007–2008. From 2002 to 2010, the median hospital hysterectomy volume\ndecreased by more than 40%. Although the relationship between volume and\noutcome for hysterectomy is less robust than for more high-risk procedures,\ndecreasing hospital volume may have important implications for quality and resource\nuse. 17 , 19 , 35\nDespite the inclusion of a large cohort of patients, we recognize a number\nof important limitations. In the Nationwide Inpatient Sample, classification of\nhysterectomy is based solely on ICD-9-CM coding and, therefore, we cannot exclude\nthe possibility that the type of procedure performed was miscoded in a small number\nof women. Because new procedures are introduced, there is a lag before the\nintroduction of an ICD-9-CM code. Although it is likely that a small number of\nlaparoscopic and robotic procedures was incorrectly classified before the\nintroduction of a claims code, this misclassification would have minimal effect\ngiven the large sample. Likewise, we lack data on clinical characteristics likely to\ninfluence the route of surgery, including prior surgical procedures, pathology,\npatient health factors, and other uterine factors. The Nationwide Inpatient Sample\nlacks data on longitudinal follow-up. As such, we lack data on whether a woman had\npreviously undergone hysterectomy and are unable to calculate age-specific rates of\nhysterectomy. This has important implications with the aging of the population and\nthe increase in the number of elderly women.\nIf the total number of hysterectomies, including both inpatient and\noutpatient procedures, falls significantly, this could result in an adverse effect\non resident training, which has already become increasingly challenging given the\nnumber of modalities now available to perform hysterectomy. A recent survey found\nthat 58% of graduating residents were “completely prepared”\nto perform an abdominal hysterectomy compared with only 28% for vaginal,\n22% for laparoscopic, and 3% for robotic hysterectomy. 36  A large number of residents are\nnow obtaining postresidency training in minimally invasive surgery as well as other\ngynecologic subspecialties. Improved surgical simulation systems may partially\ncompensate for decreasing teaching volume as well.\nThese trends also have important implications for practicing gynecologists.\nAs with hospital volumes, if the overall hysterectomy rate is declining, it will be\nassociated with lower physician case volumes. A study of laparoscopic hysterectomy\nfound that 39% of women who underwent surgery between 2000 and 2006 were\ntreated by a low-volume surgeon compared with greater than 50% from 2007 to\n2010. 17  With fewer\navailable procedures, some gynecologists may alter their practice patterns and refer\neven uncomplicated procedures to other health care providers. Based on these data,\nthe decline in the hysterectomy rate appears to be continuing and, as such, these\ntrends will likely have an important influence on the practice of gynecology going\nforward.","source_license":"public-domain-us","license_restricted":false}