Larger skeletal muscle mass tied to lower risk for type 2 diabetes in women: Study

Skeletal muscles play a critical role in regulating glucose metabolism, however, there is no clarity on the link between skeletal muscle mass and the risk of developing T2D. Therefore, Dan Liu, Sichuan University, Chengdu, China, and colleagues set out to determine the sex-specific associations between predicted skeletal muscle mass index (pSMI) and incident type 2 diabetes in a retrospective longitudinal cohort of Chinese men and women.

For this purpose, a population-based cohort study was conducted using data from the West China Adult Health Cohort. The study included adults aged 18 to 90 years who underwent annual health check-ups at the West China Hospital of Sichuan University between 2010 and 2020.

The researchers calculated pSMI using participant age, body weight, haemoglobin levels, and serum creatinine to cystatin C ratio. The study population comprised 22,415 women and 25,470 men (median age: 40 years), and the median follow-up was five years.

Based on the study, the researchers reported the following findings:

· During the follow-up period, 5.32% of men and 2.14% of women developed type 2 diabetes.

· Among all women, a higher pSMI was associated with a lower incidence of type 2 diabetes (hazard ratio [HR], 0.79).

· Among men with lower muscular mass (pSMI ≤8.1), a higher pSMI was associated with a lower risk for type 2 diabetes (HR, 0.58). This association did not persist among men with higher muscular mass.

· In the subgroup analysis, higher pSMI (8.1 for men and 6.9 for women) was associated with an increased risk for type 2 diabetes among individuals aged 50 years or older. Higher pSMI was consistently associated with a lower risk for type 2 diabetes among men (HR, 0.79) and women (HR, 0.76) under 50 years of age. There was no significant interaction between pSMI and age.

"Our findings suggest that a greater muscular mass is associated with a lower risk of type 2 diabetes in both men with diminished muscle mass and all women," the researchers concluded.

Study limitations include the pSMI being a surrogate rather than a direct measure of muscle mass, data on factors related to muscular mass such as dietary patterns and physical activity being unavailable, and a lack of data on body fat distribution and fat mass.

Reference:

Liu D, Li N, Zhou Y, et al. Sex-specific associations between skeletal muscle mass and incident diabetes: a population-based cohort study. Diabetes Obes Metab. Published online November 23, 2023. doi:10.1111/dom.15373