Reduced flexibility associated with metabolic syndrome in community-dwelling elders

Abstract

Background: The ageing process may lead to reductions in physical fitness, a known risk factor in the development of metabolic syndrome. The purpose of the current study was to evaluate cross-sectional and combined associations of metabolic syndrome with body composition and physical fitness in a community based geriatric population.

Methods: A total of 628 community-dwelling elders attending a geriatric health examination were enrolled in the study. The diagnosis of metabolic syndrome was based on the modified National Cholesterol Education Program Adult Treatment Panel III (NCEP ATP III) criterion with Asian cutoff of waist girth was adopted in this study. Body composition was obtained using bioimpedance analysis, and physical fitness was evaluated through the measurement of muscle strength (handgrip force), lower extremity muscle endurance (sit-to-stand test), flexibility (sit-and-reach test), and cardiorespiratory endurance (2-minute step test). Multivariable logistic regression and correlation analysis were performed to determine the association of metabolic syndrome with body composition and functionality variables.

Results: Metabolic syndrome was associated with increased skeletal muscle index (SMI) (odds ratio (OR), 1.61, 95% confidence interval (CI), 1.25-2.07) and decreased flexibility (OR, 0.97, 95% CI, 0.95-0.99) compared with those without metabolic syndrome. When body mass index was accounted for in the analysis, the association of SMI with metabolic syndrome was reduced. Waist circumference was positively correlated with SMI but negatively correlated with flexibility, whereas high density lipoprotein was positively correlated with flexibility but negatively correlated with SMI.

Conclusion: Reduced flexibility was positively associated with metabolic syndrome independent of age, gender, body composition, and functionality measurements in a community based geriatric population. Significant associations between metabolic syndrome with muscle strength and cardiorespiratory fitness in the elderly were not observed. Furthermore, flexibility should be included in the complete evaluation for metabolic syndrome.

Figure 1. Receiver operating characteristics (ROC) curve of skeletal muscle index (SMI) and flexibility in discriminating the presence of metabolic syndrome.

An area under the curve (AUC) of 0.5 was indicative of no discriminative value of the selected variable.