Obesity Measures and Definitions of Sarcopenic Obesity in Singaporean Adults - the Yishun Study.

OBJECTIVES: Due to the lack of a uniform obesity definition, there is marked variability in reported sarcopenic obesity (SO) prevalence and associated health outcomes. We compare the association of SO with physical function using current Asian Working Group for Sarcopenia (AWGS) guidelines and different obesity measures to propose the most optimal SO diagnostic formulation according to functional impairment, and describe SO prevalence among community-dwelling young and old adults. DESIGN: Obesity was defined according to waist circumference (WC), percentage body fat (PBF), fat mass index (FMI), fat mass/fat-free mass ratio (FM/FFM), or body mass index (BMI). SO was defined as the presence of both obesity and AWGS sarcopenia. Muscle function was compared among phenotypes and obesity definitions using ANOVA. Differences across obesity measures were further ascertained using multiple linear regressions to determine their associations with the Short Physical Performance Battery (SPPB). SETTING: Community-dwelling adults 21 years old and above were recruited from a large urban residential town in Singapore. PARTICIPANTS: 535 community-dwelling Singaporeans were recruited (21-90 years old, 57.9% women), filling quotas of 20-40 participants in each sex- and age-group. MEASUREMENTS: We took measurements of height, weight, BMI, waist and hip circumferences, body fat, muscle mass, muscle strength, and functional assessments. Questionnaire-based physical and cognitive factors were also assessed. RESULTS: Overall prevalence of SO was 7.6% (WC-based), 5.1% (PBF-based), 2.7% (FMI-based), 1.5% (FM/FFM-based), and 0.4% (BMI-based). SO was significantly associated with SPPB only in the FMI model (p<0.05), and total variance explained by the different regression models was highest for the FMI model. CONCLUSIONS: Our findings suggest FMI as the most preferred measure for obesity and support its use as a diagnostic criteria for SO.

Malnutrition and Sarcopenia in Community-Dwelling Adults in Singapore: Yishun Health Study.

OBJECTIVES: To determine the overlapping prevalence of malnutrition and sarcopenia and the association between parameters of malnutrition with muscle mass and strength in a community-dwelling Singaporean adult population. DESIGN: This was a cross-sectional study. SETTING: Large north-eastern residential town of Yishun in Singapore. PARTICIPANTS: Random sampling of community-dwelling Singaporeans aged 21-90 years old (n=541). MEASUREMENTS: Anthropometry, body composition and handgrip strength (muscle strength) were measured. Sarcopenia was identified using dual-energy x-ray absorptiometry scan (muscle mass). Nutritional status was measured using Mini Nutritional Assessment (MNA-SF). Other questionnaires collected included physical activity and cognition. Associations between nutritional status with sarcopenia as well as with muscle mass and strength were analysed using multinomial logistics and linear regressions. RESULTS: The overall population-adjusted prevalence of those at nutritional risk and malnourished were 18.5% and 0.1% respectively. More than a third of participants (35%) who were at nutritional risk were sarcopenic. Malnourished participants were all sarcopenic (100%, N=2) whereas those who were sarcopenic, 27.0% (N=37) were at nutritional risk/malnourished. Being at nutritional risk/malnourished was significantly associated with 2 to 3 times increased odds of sarcopenia in multivariate analyses adjusting for age, gender, physical activity level and cognition, and fat mass index. Favourable MNA parameter scores on food intake and BMI were positively associated with greater muscle mass and handgrip strength (p<0.05). CONCLUSION: Given the overlapping clinical presentation of malnutrition and sarcopenia, community screening protocols should include combination screening of nutritional status and sarcopenia with appropriate interventions to mitigate risk of adverse health outcomes.