Frailty, dependency and mortality predictors in a cohort of Cuban older adults, 2003-2011.

INTRODUCTION: Population aging translates into more people with chronic non-communicable diseases, disability, frailty and dependency. The study of frailty--a clinical syndrome associated with an increased risk of falls, disability, hospitalization, institutionalization and death--is important to improve clinical practice and population health indicators.
OBJECTIVES: In a cohort of older adults in Havana and Matanzas provinces, Cuba, estimate prevalence of frailty and its risk factors; determine incidence of dependency; estimate mortality risk and identify mortality predictors.
METHODS: A prospective longitudinal study was conducted door to door, from June 2003 through July 2011, in a cohort of 2813 adults aged ≥65 years living in selected municipalities of Havana and Matanzas provinces; mean followup time was 4.1 years. Independent variables included demographics, behavioral risk factors and socioeconomic indicators, chronic non-communicable diseases (hypertension, stroke, dementia, depression, diabetes, anemia), number of comorbidities, and APOE ε4 genotype. Dependent variables were frailty, dependency and mortality. Criteria for frailty were slow walking speed, exhaustion, weight loss, low physical activity and cognitive decline. Prevalence and frailty risk were estimated by Poisson regression, while dependency and mortality risks and their predictors were determined using Cox regression.
RESULTS: Frailty syndrome prevalence was 21.6% (CI 17.9%-23.8%) at baseline; it was positively associated with advanced age, anemia and presence of comorbidities (stroke, dementia, depression, three or more physically debilitating diseases). Male sex, higher educational level, married or partnered status, and more household amenities were inversely associated with frailty prevalence. In followup, dependency incidence was 33.1 per 1000 person-years (CI 29.1-37.6) and mortality was 55.1 per 1000 person-years. Advanced age, male sex, lower occupational status during productive years, dependency, frailty, dementia, depression, cerebrovascular disease and diabetes were all associated with higher risk of death.
CONCLUSIONS: Given the challenge for developing countries presented by demographic and epidemiologic transition; the high prevalence in older adults of frailty syndrome, dependency and chronic non-communicable diseases; and the association of all these with higher mortality, attention should be targeted to older adults as a risk group. This should include greater social protection, age-appropriate health services, and modification and control of cardiovascular risk factors.