Metabolic syndrome and insulin resistance are associated with frailty in older adults: a prospective cohort study

Background: diabetes increases the risk of frailty that is a leading cause of disability and premature mortality in older people. Metabolic syndrome (MS) and insulin resistance (IR) are strong risk factors for diabetes and could, thus, lead to frailty. However, the association between MS or IR and frailty has barely been investigated.

Methods: data were obtained from a cohort of 1,499 community-dwelling individuals aged ≥60, who were free of diabetes at 2008-10 and were followed up for 3.5 years. At baseline, MS was ascertained according to the harmonised definition, and IR with the Homoeostatic Model Assessment for IR index (HOMA-IR). Frailty was defined as having three or more of the Fried's criteria: exhaustion, low physical activity, slow walking, unintentional weight loss and low grip strength. Statistical analyses were performed with logistic regression, and adjusted for the main confounders.

Results: in 2012, 84 cases of incident frailty were identified. Compared with subjects without MS, those with MS showed increased risk of frailty (multivariate odds ratio [OR]: 1.85; 95% confidence interval [CI] 1.12-3.05). The association persisted after further adjustment for fibrinogen and C-reactive protein. When the frailty criteria were considered individually, low grip strength was the criterion that showed a stronger association with MS (OR: 1.67; 95% CI: 1.25-2.21). Higher HOMA-IR values were also associated with higher risk of frailty.

Conclusion: MS and IR were associated with increased risk of frailty. This work extends the spectrum of harmful consequences of MS, and suggests that preventing or controlling MS may serve to delay frailty.