THE COMBINATION OF RENAL DYSFUNCTION AND MUSCLE MASS REDUCTION IS ASSOCIATED WITH ARTERIAL STIFFNESS IN ELDERLY INDIVIDUALS

Abstract

Objective: Epidemiological studies have found that both renal dysfunction and muscle mass reduction (sarcopenia) are associated with the target organ damage and future risk of cardiovascular disease. This study aimed to examine whether the renal dysfunction, muscle mass reduction, and their combination related to arterial stiffness among elderly individuals. Design and method: From the participants in Wakayama study, a total of 552 normotensive and untreated hypertensive elderly individuals (mean age, 69.5 ± 3.6 years) without a history of stroke, coronary heart disease and renal disease was enrolled in this study. Brachial-ankle pulse wave velocity (baPWV) was measured by a simple automatic oscillometric technique and used as index of arterial stiffness. The skeletal muscle mass(SM) of the whole body was estimated by a bioelectrical impedance analysis. The renal dysfunction was evaluated by a glomerular filtration rate (eGFR) correlated by body surface area. Results: The eGFR and SM of subjects decreased with increase in age, and the values were significantly higher in men than women. The eGFR was positively correlated with SM in both genders. We divided the subjects into four groups according to eGFR and SM levels; namely, high-eGFR (> = 60 ml/min/1.73 m2) + high SM (> = age- and gender-specific median value) group (n = 228), high-eGFR + low-SM group (n = 189), low-eGFR + high-SM group (n = 58) and low-eGFR + low-SM group (n = 77). There was no significant difference in blood pressure between the four groups. The baPWV was the highest in the low-eGFR + low-SM group (1,751 cm/s), and followed by the high-eGFR + low-SM group (1,708 cm/s), the low-eGFR + high-SM group (1,687 cm/s) and the high-eGFR + high-SM group (1,610 cm/s). After adjustment for age and gender, the baPWV in the high-eGFR + low-SM group was significantly higher than that in the high-eGFR + high-SM group (p = 0.006); whereas no significant difference between the low-eGFR + high-SM group and the high-eGFR + high-SM group (p = 0.502). Conclusions: In elderly individuals, the combination of renal dysfunction and muscle mass reduction may contribute to the acceleration of arterial stiffening relative to the condition that they exist solely.