LOW SKELETAL MUSCLE MASS IS ASSOCIATED WITH INCREASED ARTERIAL STIFFNESS IN COMMUNITY-DWELLING ELDERLY INDIVIDUALS

Abstract

Objective: Age-related decline of skeletal muscle mass, known as sarcopenia, is related to insulin resistance, inflammation, and oxidative stress. The aim of this study was to investigate the association between low skeletal muscle mass and arterial stiffness in a community-dwelling elderly individuals. Design and method: Study participants consisted of general population who participated in the Wakayama Health Promotion Study (the Wakayama Study). Of the participants, 1795 apparently healthy elderly individuals (mean age; 71 ± 5 years) without a history of treatment for cardiovascular disease, renal disease and orthopedic disease were enrolled in this study. Bioelectrical impedance analysis was performed to estimate appendicular skeletal muscle mass (ASM). A value of ASM was normalized for height and conversed to an ASM index. The brachial-ankle pulse wave velocity (baPWV) was measured using a simple automatic oscillometric technique with an appropriate size cuff. Results: The ASM and ASM index were 11.1 ± 2.5 kg and 4.4 ± 0.7 kg/m2 respectively, and were significantly lower in females than in males (p < 0.001). The subjects were divided into subgroups according to sex-specific percentiles of ASM index and were defined as sarcopenic group (<15 percentile) and normal group (>=15 percentile). In females and males, the baPWV was significantly higher in sarcopenic group than normal group after adjusting for potential confounders (females: 17.7 ± 4.1m/s vs. 17.2 ± 3.3m/s, P = 0.001; males: 18.6 ± 4.0m/s vs. 17.4 ± 3.5m/s, P < 0.001). Multiple regression analysis revealed that ASM index was associated with baPWV independent of age, obesity, systolic BP, antihypertensive medication and diabetes mellitus (females: β = −0.147, P < 0.001; males: β = −0.192, P < 0.001). Conclusions: In elderly individuals, the excessive loss of skeletal muscle mass is significantly associated with increase of arterial stiffness, and may lead to greater risk of cardiovascular events.