# Impact of Sarcopenia, Dynapenia, and Obesity on Muscle Strength and Quality in Chronic Kidney Disease Patients: A Sex-Specific Study

## TL;DR

This study finds that men on hemodialysis have worse muscle strength and quality than women, and obesity worsens muscle quality in both sexes.

## Contribution

The study provides sex-specific insights into muscle dysfunction and obesity's impact in CKD patients.

## Key findings

- Men had significantly lower muscle strength and quality compared to women.
- Excess adiposity was independently linked to poorer muscle quality in both sexes.
- Men were more likely to have dynapenia and sarcopenia than women.

## Abstract

Sex-specific differences in the prevalence of sarcopenia, dynapenia, and the impact of obesity on muscle strength and quality in patients with chronic kidney disease (CKD) remain underexplored. Background/Objectives: In this cross-sectional study, 78 adults with stage 5 CKD undergoing thrice-weekly maintenance hemodialysis in Brazil (44 men, 34 women; mean ± SD age = 57.55 ± 4.06 years) were assessed. Anthropometry (BMI, waist circumference, waist-to-height ratio), dual-energy X-ray absorptiometry, circulating IL-6, Timed Up and Go, handgrip strength (Jamar ® dynamometer), and muscle quality index (MQI = handgrip/BMI) were obtained. Dynapenia (handgrip < 27 kg men and < 16 kg women) and sarcopenia (1.0 kg/kg for men and 0.56 kg/kg for women) were classified using EWGSOP2-2018 and FNIH thresholds. Results: Compared with reference values, men showed markedly reduced muscle strength and muscle quality (men: handgrip 21.3 ± 5.1 kg; MQI 0.80 ± 0.23 AU) than women. Also, men were 5.1 times more likely to present with dynapenia (88.6%; 95% CI 2.28–11.60) and 3.15 times more likely to present with sarcopenia (75.0%; 95% CI 1.88–5.30) than women. Waist circumference, waist-to-height ratio, BMI, and body fat % correlated inversely with MQI in both sexes (p ≤ 0.01) and with handgrip strength in men (p ≤ 0.01) but not in women. Conclusions: Among hemodialysis patients, men exhibit a substantially higher burden of dynapenia and sarcopenia than women and excess adiposity is independently associated with poorer muscle quality in both sexes. These findings highlight the need for sex-specific screening cut-offs and integrated strategies targeting both muscle dysfunction and central obesity in CKD management.