Article

Sarcopenia refers to the loss of skeletal muscle mass with aging. It
is believed to be associated with functional impairment and physical disability.
The purposes of this study were: (1) to compare the physical activity,
muscle strength (force-generating capacity), cardiopulmonary fitness, and
physical disability in community-dwelling elderly people with sarcopenia,
borderline sarcopenia, and normal skeletal muscle mass in Taiwan and (2) to test
the hypothesis that sarcopenia is associated with physical disability and examine
whether the association is mediated by decreased muscle strength or
cardiopulmonary fitness. DESIGN: This was a cross-sectional investigation.
METHODS: Two hundred seventy-five community-dwelling elderly people (148 men, 127
women) aged > or =65 years participated in the study. The participants were
recruited from communities in the district of Zhongzheng, Taipei. Predicted
skeletal muscle mass was estimated using a bioelectrical impedance analysis
equation. The skeletal muscle mass index (SMI) was calculated by dividing
skeletal muscle mass by height squared. Physical disability was assessed using
the Groningen Activity Restriction Scale. Physical activity was assessed using a
7-day recall physical activity questionnaire. Cardiopulmonary fitness was
assessed using a 3-minute step test, and grip strength was measured to represent
muscle strength. RESULTS: Cardiopulmonary fitness was significantly lower in
elderly people with sarcopenia than in those with normal SMIs. Grip strength and
daily energy expenditure (kcal/kg/day) were not significantly different between
the participants with sarcopenia and those with normal SMIs. The odds ratio for
physical disability between the participants with sarcopenia and those with
normal SMIs was 3.03 (95% confidence interval=1.21-7.61). The odds ratio
decreased and the significant difference diminished after controlling for
cardiopulmonary fitness. LIMITATIONS: A causal relationship between sarcopenia
and physical activity, cardiopulmonary fitness, and physical disability cannot be
established because of the cross-sectional nature of study design. CONCLUSIONS:
Sarcopenia was associated with physical disability in elderly men. The
association between sarcopenia and physical disability was mediated to a large
extent by decreased cardiopulmonary fitness.

Langue : ANGLAIS