Associated factors and health impact of sarcopenia in older chinese men and women: a cross-sectional study.

BACKGROUND: Sarcopenia is increasingly being recognized as a feature of frailty in old age and is associated with unfavorable health outcomes in Western populations. Little is known about sarcopenia among Asian elderly populations.
OBJECTIVES: The study was undertaken to study the association between sarcopenia and common chronic illnesses, lifestyle factors, psychosocial well-being and physical performance.
METHODS: 4,000 community-dwelling Chinese elderly >/=65 years were recruited. Medical illnesses, cigarette smoking, alcohol consumption, physical activity level and psychosocial well-being scores were recorded. Physical performance measured included grip strength, timed chair-stands, stride length and a timed 6-meter walk. Muscle mass was measured using dual-energy X-ray absorptiometry. Relationships between appendicular skeletal muscle mass (ASM/ht(2)) and multiple variables were analyzed using uni- and multivariate analyses.
RESULTS: Mean ASM/ht(2) was 7.19 and 6.05 kg/m(2) in men and women respectively. Older age, cigarette smoking, chronic lung disease, atherosclerosis, underweight, and physical inactivity were associated with low adjusted ASM, which was in turn associated with poorer physical well-being in men. After adjustment to age, lower appendicular muscle mass was associated with weaker grip strength in both sexes. In men, lower limb tests (chair-stands, walking speed and step length) were not related to ASM, while in women, lower muscle mass was not associated with poorer lower limb muscle performance.
CONCLUSIONS: Sarcopenia in community-dwelling older Chinese men and women was associated with cigarette smoking, chronic illnesses, underweight, physical inactivity, poorer well-being and upper limb physical performance. Copyright 2007 S. Karger AG, Basel.