Aim: Decreased muscle mass has been suggested to be a risk factor for arterial stiffness in older population, though evidence in a large-scale study is lacking. Furthermore, it is unclear whether the association can be extrapolated to middle-aged population, where loss of muscle mass and arterial stiffening begins to occur. We aimed to clarify the association between muscle mass and arterial stiffness in a large general population including a wide age ranged individuals.
Method: We analyze a dataset of the Nagahama study. Muscle mass was assessed using skeletal muscle index (SMI) obtained by a bioelectrical impedance analysis. Arterial stiffness was assessed by brachial to ankle pulse wave velocity (baPWV).
Results: Study population consisted of 9,740 individuals (58 ± 12 years old). baPWV was significantly higher in men (n = 3,138, 1346 ± 236 cm/sec) than women (n = 6,602, 1256 ± 230 cm/sec), and showed positive relationship with systolic blood pressure (r = 0.669). SMI also showed significant sex difference (men: 7.7 ± 0.7, women: 6.2 ± 0.6 kg/m2). However, SMI was identified as an independent inverse determinant for baPWV (β = -0.196, P < 0.001) in a regression model adjusted for age, sex, body height, body weight, systolic blood pressure, Brinkman index, and antihypertensive medication. Further the association between SMI and baPWV remained significant in a separate analysis at 65 years old (older population: β = -0.256, P < 0.001, middle-aged population: β = -0.189, P < 0.001).
Conclusion: Low skeletal muscle mass is an independent risk factor for arterial stiffness even in a middle-aged population.

05 - LOW SKELETAL MUSCLE MASS IS AN INDEPENDENT RISK FACTOR FOR ARTERIAL STIFFNESS: THE NAGAHAMA STUDY