Sex- and Age-Specific Associations Between Metabolic Syndrome and Future Functional Disability in the Japanese Older Population

Abstract

Whether the association between metabolic syndrome (MetS) and functional disability differs depending on sex or age remains unknown. To determine the association between MetS and functional disability in older people separately by sex and age groups. A total of 11 083 participants (4407 men and 6676 women) aged 65 years or over without functional disability were enrolled. MetS was defined according to the revised NCEP ATP III guidelines. Functional disability was defined by a new certification in the long-term care insurance in Japan. Cox proportional hazards models were used to assess the risk of functional disability with adjustment for possible confounding factors. Over the mean observation period of 10.5 years, 1282 men and 2162 women experienced functional disability. For those aged 65 to 74 years, HRs (95% CIs) for functional disability in the MetS group were 1.33 (1.07-1.66) in men and 1.15 (1.000-1.32) in women. For those aged 75 years or older, there was no significant association in men or women. In subjects with a severe care need level, there was a marginal significant association in men aged 65 to 74 years. Among the MetS components that independently increased the risk of functional disability were glucose intolerance and elevated blood pressure (men and women aged 65-74 years), obesity (women aged 65-74 years), and glucose intolerance (women aged 75 years or older). MetS contributed to an increase in a high risk of future functional disability among individuals aged 65 to 74 years. In this age group, improvement of lifestyle, health promotion and interventions for MetS from middle age may prevent future functional disability.