Effect of basal metabolic rate on the development of sarcopenia, a Mendelian randomization study

Abstract Backgrounds There are various studies linking basal metabolic rate (BMR) and sarcopenia, but the causal relationship remains uncertain. We conducted a Mendelian random (MR) analysis to investigate the causal association between BMR and sarcopenia. Methods The inverse variance weighting approach was utilized as the primary method for Mendelian random analysis. This study analyzed the causal relationships between BMR and sarcopenia, and BMR as the exposure factor and characteristics associated with sarcopenia (grip strength, lean body mass, walking pace) as outcome indicators. To ensure the accuracy of our analysis, we conducted a sensitivity analysis using Cochran’s Q test, MR-Egger intercept test, leave-one-out analysis, and the funnel plot technique. Results Our study found that there was a positive relationship between BMR and grip strength in both the right hand (IVW: β = 0.30, 95% CI, 0.28-0.32, p=1.47e−159) and left hand (IVW: β = 0.28, 95% CI, 0.26-0.31, p=1.26e−149). We also observed a positive correlation between BMR and whole lean body mass (IVW: β = 0.97, 95% CI, 0.96-0.98, p=0.00), appendicular lean mass (IVW: β = 1.36, 95% CI, 1.32-1.41, p=0.00), and walking pace (IVW: β = -0.05, 95% CI, -0.07−-0.03, p=1.18e−8). Furthermore, we found that a lower BMR was associated with a higher risk of having low hand grip strength (OR =0.56; 95% CI, 0.52-0.60; P=4.97e−54). Conclusion MR analysis revealed that individuals with a higher BMR have a lower risk of developing sarcopenia, indicating an inverse causal relationship between BMR and sarcopenia.