Association between a lifestyle-based healthy heart score and risk of frailty in older women: a cohort study

Abstract Background Evidence on the comprehensive role of lifestyle in frailty risk is scarce. To assess the association between a lifestyle-based Healthy Heart Score (HHS), which estimates the 20-year risk of cardiovascular disease (CVD), and risk of frailty among older women. Methods Prospective cohort study in 121,700 nurses from the USA participating at the Nurses’ Health Study. This study included 68,416 women aged ≥60 year with a follow-up from 1990 to 2014. The HHS was computed using the gender-specific beta-coefficients of the nine lifestyle factors, including current smoking, high body mass index, low physical activity, lack of moderate alcohol intake and unhealthy diet. Frailty incidence was assessed every 4 years from 1992 to 2014 as having ≥3 of the following five criteria from the FRAIL scale: fatigue, low strength, reduced aerobic capacity, having ≥5 illnesses and weight loss ≥5%. Results During 22 years of follow-up, 11,041 total incident cases of frailty were ascertained. Compared to women in the lowest quintile of the HHS (lowest estimated CVD risk), the multivariable-adjusted hazard ratio of frailty across quintiles was: Q2:1.67 (95% confidence interval 1.53, 1.82); Q3: 2.34 (2.15, 2.53); Q4: 3.54 (3.28, 3.83) and Q5: 5.92 (5.48, 6.38); P-trend > 0.001. Results were consistent for each frailty criterion, among participants with 0 frailty criteria at baseline, when using only baseline exposure or in 6-year-, 10-year- and 14-year-exposure lagged analyses, and after excluding participants with diabetes and CVD at baseline. Conclusions The HHS, based on a set of modifiable-lifestyle factors, is strongly associated with risk of frailty in older women.