There is a close association between sarcopenia and diabetic peripheral neuropathy (DPN), according to study results published in Diabetes Research and Clinical Practice.
Sarcopenia may lead to reduced exercise and increased risk for microvascular complications in patients with diabetes mellitus, including nephropathy and retinopathy. Because there is little information on the association between sarcopenia and DPN, the goal of the current cross-sectional study was to explore this association. In addition, a cohort study was carried out to investigate the changes in muscle mass and nerve conduction velocity.
The cross-sectional study included 1794 individuals (937 men; mean age, 60.22 years). Of these, 183 patients (98 men; mean age, 59.08 years) were enrolled in the follow-up study with a median follow-up of 2.7 years.
All patients underwent nerve conduction tests and muscle mass index was calculated using the following formula: appendicular skeletal muscle mass (ASM; in kg) divided by height squared (HT2; in m2 [ASM/HT2]). The composite z scores for the sensory nerve conduction velocity (SCV) and motor nerve conduction velocity (MCV) were calculated. The changes in ASM/HT2, SCV, and MCV were calculated from the measurements approximately 2 years apart and changes in skeletal muscle were classified into 3 groups: a decrease in ASM/HT2 of >3%, a minor change within ±3%, or an increase of >3%.
In men, the multivariate regression analysis showed that muscle mass index was positively associated with the median (β=0.928; P <.001), ulnar (β=1.462; P <.001), peroneal (β=1.059; P =.001), and tibial MCV (β=0.839; P =.001) among the motor neurons; the median (β=1.499; P <.001), ulnar (β=0.837; P =.044), peroneal (β=2.090; P =.002), and sural SCV (β=1.257; P =.014) among the sensory neurons; and the composite z scores of MCV (β=0.197; P <.001) and SCV (β=0.3000; P <.001).
Receiver operating characteristic analysis indicated that the optimal cutoff point for ASM/HT2 that indicated DPN was 7.09 kg/m2 (area under the curve, 0.605; 95% CI, 0.569-0.642; sensitivity, 53.1%; specificity, 72.3%).
No significant correlations were found between ASM/HT2 and MCV, SCV and neuropathy score, and DPN and sarcopenia in women.
In the follow-up cohort study, there was a strong positive association between 2-year changes in skeletal muscle and nerve conduction velocity. During the follow-up period, nerve conduction velocity increased in terms of the partial motor and sensory velocities with an increase in the muscle mass in men with diabetes. However, similar to the findings in the cross-sectional analysis, this phenomenon was generally not observed in women with diabetes.
The researchers noted several limitations to the study, including possible selection bias as the study was performed in a hospital and included mainly middle-aged adults with nonsevere diabetes. As such, the findings may not be generalizable to older patients.
“The assessment of muscle mass may have clinical implications in the prevention of DPN in men with diabetes,” concluded the researchers.
Zhang Y, Shen X, He L, Zhao F, Yan S. Association of sarcopenia and muscle mass with both peripheral neuropathy and nerve function in patients with type 2 diabetes [published online February 25, 2020]. Diabetes Res Clin Pract. doi:10.1016/j.diabres.2020.108096