THE PHENOTYPE OF FRAILTY PREDICTS DISABILITY AND MORTALITY AMONG MEXICAN COMMUNITY-DWELLING ELDERLY

Abstract

Background: Frailty represents a major public health priority in Western countries. Specific social and cultural factors may influence the prevalence and predictive value for negative health-related events of this syndrome. Objective: To determine the prevalence and predictive value of the phenotype of frailty among community-dwelling Mexican American older persons. Design, Setting and Participants: Two-year longitudinal study of 5,644 men and women aged 60 years and older participating in the Mexican Health and Aging Study. Measurements: The Frailty index used in the present study was a modified version of the operational definition proposed in the Cardiovascular Health Study (CHS). Frailty was defined by the presence of at least three of the four following criteria: weight loss, weakness, exhaustion, slowness, and low physical activity. The main outcomes were incident disability and mortality. Chi-square, ANOVA and multiple logistic regression analyses were used to test the prognostic value of frailty for the outcomes of interest. Results: The mean age of the study sample was 68.7 (SD 6.9) years. Thirty-seven percent of participants (n=2,102) met the definition of frailty. Frail subjects were significantly older, and more likely to be women than non-frail participants. They also presented lower education, more chronic diseases, lower income, and poorer self-reported health status. After adjusting for potential confounders, frailty was found to be a predictor of incident mobility disability (odds ratio [OR] 1.91, 95% confidence interval [CI] 1.37-2.66), activities of daily living (ADL) disability (OR 9.33; 95%CI 3.37-25.82), and instrumental ADL (IADL) disability (OR 1.81, 95%CI 1.23-2.68). The risk of mortality among frail participants was almost three-fold higher than in non-frail ones. Conclusion: The prevalence of frailty is higher in this elderly population than what previously reported in other cohorts. The phenotype of frailty was confirmed to be a predictor for adverse health-related outcomes (including mobility, ADL, and IADL disability). Further studies in Latin American countries are needed to identify frailty and develop adapted interventions for the prevention of adverse outcomes in older persons.