Waist circumference is an important determinant of relative muscle strength in patients with type 2 diabetes mellitus.

Abstract

Background: Muscle damage has recently been recognized as a complication of type 2 diabetes mellitus (T2DM). Impaired muscle function adversely affects physical activity, quality of life, and mortality risk. Moreover, waist circumference (WC) is associated with visceral fat and insulin resistance. This study investigated the correlation between relative muscle strength and WC in patients with T2DM.

Methods: Patients aged 50 years or older with T2DM were recruited from Taipei Veterans General Hospital. WC was measured at the umbilicus level. Total muscle mass was assessed using bioelectrical impedance analysis. The muscle strength of handgrip, knee extension, ankle dorsiflexion, and ankle plantar flexion were evaluated using a hand-held dynamometer.

Results: A total of 252 patients (mean age 69.4 years; 122 men and 130 women) were enrolled. They were stratified into three groups according to WC (<85, 85-94, >94 cm). Patients with a larger WC had a higher body mass index and greater muscle mass but had lower relative muscle strength of handgrip, knee extension, ankle dorsiflexion, and ankle plantar flexion. Of note, patients with abdominal obesity (WC ≥90 cm in men and WC ≥80 cm in women) had significantly lower relative muscle strength of handgrip and lower limb compared to those without in both sexes. Multivariable analyses revealed that WC was significantly and negatively correlated with relative muscle strength after adjusting for other clinical variables.

Conclusion: WC, independent of muscle mass, is a good determinant of relative muscle strength in patients with T2DM. Measuring WC can help identify patients with T2DM at a high risk of low relative muscle strength, thereby broadening the scope of health screening in this population.