FP769IS THERE ASSOCIATION BETWEEN MUSCLE STRENGTH AND BODY COMPOSITION PARAMETERS IN ELDERLY PATIENTS ON HEMODIALYSIS?

Abstract

Introduction and Aims: Chronic kidney disease, hemodialysis (HD) and aging can lead to diminished muscle mass and muscle strength. However, it is not clear whether the reduction of strength in elderly on HD is accompanied by a reduction in body composition parameters. Thus, we aimed to evaluate whether changes in handgrip strength (HGS) are associated with changes in body weight, body fat (BF%), fat free mass (FFM) and skeletal muscle mass (SMM) in elderly on HD. Methods: Observational, longitudinal and prospective study including 66 elderly (≥60 years) on HD. All patients underwent anthropometric measurements, bioelectrical impedance (BIA), HGS (by dynamometer), serum albumin, SMM (by BIA), and subjective global assessment for assessment of protein energy wasting (PEW). After 12 months, the same protocol applied at baseline was repeated. Groups were built according to the HGS change (final value ‐ initial): HGS Gain Group (HGS‐Gain): gain ≥1kg; HGS Loss Group (HGS‐Loss): loss ≥1kg and HGS Maintenance Group (HGS‐M): no change. Results: Out of 66 patients, 32 gained strength (HGS min:1kg, max: 8kg), 20 showed lost strength (HGSmin: 2kg, max: 6kg) and 14 have not changed the HGS. When comparing the 3 groups we noted that the HGS‐Gain group had a significantly lower age (HGS‐Gain: 69.4±5.8 years; HGS‐Loss: 71.2±6.7 years; HGS‐M: 77.7±6.3 years; P=0.001), lower proportion of PEW (HGS‐Gain: 43.8%; HGS‐Loss: 75%; HGS‐M: 71.4%, P=0.04) and higher albumin (HGS‐Gain: 4.2 (3.9; 4.4)g/dL (median and 25th‐75th percentile), HGS‐Loss: 3.9 (3.5; 4.1)g/dL, HGS‐M: 3.7 (3.5; 3.8)g/dL, P <0.001). The proportion of males and diabetes, length of dialysis, body weight and BMI were similar among groups. Bivariate correlations were conducted with all patients and then separately within the groups. When evaluating all patients and HGS‐Gain group, no significant associations between changes in HGS and changes in body weight, BF%, FFM and SMM were observed. In the HGS‐Loss group, a negative association was observed between loss in HGS and changes in BF% (r= ‐0.56, P=0.01), implying that higher decline in HGS was associated with higher BF% gain over 12 months. In addition, a similar trend was observed between loss in HGS and changes in body weight (r= ‐0.40, P=0.08). For the HGS‐Loss group, the linear regression analysis adjusted for gender and age showed that a greater decline in HGS was associated with higher gain in BF% (ß= ‐0.57, P=0.005). Conclusions: Over 12 months of follow up, there was no association between changes in HGS and changes in body composition parameters in the total group. In addition, our results suggested that the group that gained strength had better overall condition indicated by the younger age, lower prevalence of PEW and increased albumin concentration. Finally, the group that lost strength was associated with an increased gain in BF%, suggesting that this body compartment seems to negatively influence change in strength in elderly patients on HD.