Low muscle mass in older men: the role of lifestyle, diet and cardiovascular risk factors

OBJECTIVE: To explore associations between low muscle mass and a wide range of lifestyle, dietary and cardiovascular risk factors in older men including metabolic risk factors, markers of inflammation, endothelial dysfunction and coagulation.

DESIGN: Cross-sectional study.

SETTING: British Regional Heart Study.

PARTICIPANTS: 4252 men aged 60-79 years.

MEASUREMENTS: PARTICIPANTS attended a physical examination in 1998-2000, and completed a general questionnaire and a food frequency questionnaire. Low muscle mass was assessed by two measures: midarm muscle circumference (MAMC) and fat-free mass index (FFMI). Associations between risk factors and low muscle mass were analysed using logistic regression.

RESULTS: Physical inactivity, insulin resistance, C-reactive protein, von Willebrand factor and fibrinogen were associated with significantly increased odds of low MAMC and FFMI after adjustment for body mass index, lifestyle characteristics and morbidity. Those with higher percent energy intake from carbohydrates showed decreased odds of low MAMC (OR: 0.73, 95% CI: 0.55-0.96) and FFMI (OR: 0.76, 95% CI: 0.58-0.99). Other dietary variables, smoking, alcohol intake, D-dimer, interleukin 6 and homocysteine showed no important associations with MAMC and FFMI.

CONCLUSION: Increasing physical activity, consuming a diet with a high proportion of energy from carbohydrates, and taking steps to prevent insulin resistance and reduce inflammation and endothelial dysfunction may help to reduce the risk of low muscle mass in older men.