Assessment of Handgrip Strength and Cardiac Autonomic Neuropathy Using Cardiovascular Autonomic Reflex Tests and Heart Rate Variability in Adults With Type 2 Diabetes Mellitus: A Single-Center Comparative Cross-Sectional Study

Introduction: Type 2 diabetes mellitus (T2DM) is associated with both neuromuscular impairment and diabetic autonomic neuropathy, including cardiac autonomic neuropathy (CAN).However, the relationship between handgrip strength (HGS) and cardiac autonomic dysfunction remains insufficiently characterized.This study aimed to compare HGS and cardiac autonomic parameters between adults with T2DM and healthy controls and to examine factors associated with definite CAN.Methods: This comparative cross-sectional study included 120 adults aged 30-65 years, comprising 60 participants with T2DM and 60 age-and sex-matched controls.HGS was assessed using a calibrated dynamometer, while cardiac autonomic function was evaluated using cardiovascular autonomic reflex tests and heart rate variability analysis.Correlation analysis and multivariable logistic regression were performed.Results: Participants with T2DM had significantly lower dominant, non-dominant, and relative HGS than controls (p<0.001).Cardiac autonomic assessment demonstrated reduced standard deviation of normal-tonormal RR intervals (SDNN) and root mean square of successive RR interval differences (RMSSD) and an increased low-frequency/high-frequency (LF/HF) ratio in the T2DM group (p<0.001 for all).Definite CAN was present in 20 (33.33%) participants with T2DM compared with four (6.67%) controls.HGS was positively associated with SDNN, RMSSD, and cardiovascular autonomic reflex indices and negatively associated with HbA1c, resting heart rate, and LF/HF ratio.Longer diabetes duration, higher HbA1c, and low HGS were independently associated with definite CAN.Low HGS showed the strongest association with definite CAN (adjusted OR=3.58, 95% CI: 1.13-11.31,p=0.030).Conclusion: Adults with T2DM demonstrated lower HGS and greater cardiac autonomic dysfunction than healthy controls.Reduced HGS was independently associated with definite CAN after adjustment for relevant clinical factors.These findings suggest that HGS may have potential clinical value as a simple adjunctive measure when assessing autonomic involvement in adults with T2DM.