Impaired muscle quality and physical performance in diabetic neuropathy: associations with skeletal characteristics from the Deep Phenotyping Study.

Aims

We examined whether diabetic neuropathy is associated with altered muscle morphology, strength, and physical performance, and whether muscle characteristics relate to skeletal health.

Methods

In this cross-sectional study, 123 individuals with type 2 diabetes were classified into +/- neuropathy based on peripheral and autonomic assessments. Tibial muscle morphology and bone microarchitecture were assessed using high-resolution peripheral quantitative computed tomography, while dual-energy X-ray absorptiometry assessed appendicular lean mass (ALM/height2) and femoral neck bone mineral density (FN aBMD). Muscle strength was evaluated by handgrip and knee extension, and physical performance by chair stand test (CST), timed up-and-go (TUG), and usual gait speed (UGS). Associations were examined using multivariate linear regression adjusted for age, sex, and BMI.

Results

Neuropathy was associated with lower muscle volume and density, but not ALM/height2 or muscle strength. Individuals with neuropathy performed fewer CST repetitions, had longer TUG times, and slower UGS. Higher muscle density was associated with higher FN aBMD, favorable cortical bone parameters, and greater estimated bone strength.

Conclusions

Diabetic neuropathy is associated with lower distal muscle density and volume, poorer physical performance but preserved strength and ALM. Associations between muscle density and bone characteristics suggest an interrelationship between neuropathy, muscle quality and skeletal fragility in type 2 diabetes.