The relationship between skeletal muscle mass and arterial stiffness in an elderly Korean population

Abstract

Introduction:Several studies have examined the relationship between skeletal muscle mass and arterial stiffness. The results, mostly, have shown an inverse relationship between skeletal muscle mass and arterial stiffness. But, there were only few studies to examine the relationship between skeletal muscle mass and arterial stiffness targeting an elderly Korean population. Thus, the aim of this study is to investigate the relationship between skeletal muscle mass and arterial stiffness in an elderly Korean population.Methods:This study used data from the Korean Social Life, Health and Aging Project (KSHAP) which started in 2011. A total of 814 people agreed to participate in the KSHAP, and 533 participants completed both questionnaire survey and health examinations. Skeletal muscle mass was measured with bioelectrical impedance analysis method using Inbody370 (Biospace, Seoul, Korea). Augmentation index, an indicator of systemic arterial stiffness, was measured by HEM-9000AI (Omron Healthcare, Kyoto, Japan) and adjusted to heart rate of 75 bpm. In this cross-sectional study, 180 men and 247 women aged 52-95 years were included, after excluding people missing augmentation index measurements (n=91), arm and leg muscle mass (n=15), or laboratory tests (n=17). The relationship between skeletal muscle mass and arterial stiffness was investigated by multiple linear regression analysis.Results:Mean age was 71.7 in men and 70.9 in women. In male participants, arm and leg muscle masses were inversely associated with augmentation index when adjusted for age (p=0.0003 and p=0.0007, respectively), and even after additional adjustment for body mass index, brachial systolic blood pressure, total cholesterol, high-density lipoprotein-cholesterol, fasting glucose and insulin, smoking and alcohol intake (p=0.025 and p=0.029, respectively). In women, arm muscle mass was not

significantly associated with augmentation index. Leg muscle mass was associated with augmentation index when adjusted for age (p=0.03) but the association disappeared when fully adjusted (p=0.23). Skeletal muscle mass was not significantly associated with brachial blood pressure in both sexes.Conclusion:Decreased skeletal muscle mass was independently associated with arterial stiffness but not with resting brachial blood pressure in an elderly Korean population. Our results suggest that an age-related loss of skeletal muscle mass may affect arterial wall elasticity rather than resting blood pressure.