Aging and Alzheimer is a prospective, longitudinal cohort study involving 2944 adults aged ≥65 years from selected areas in Cuba’s Havana and Matanzas Provinces. This door-to-door study, which began in 2003, includes periodic assessments of the cohort based on an interview; physical exam; anthropometric measurements; and diagnosis of dementia and its subtypes, other mental disorders, and other chronic non-communicable diseases and their risk factors. Information was gathered on sociodemographic characteristics; disability, dependency and frailty; use of health services; and characteristics of care and caregiver burden. The first assessment also included blood tests: complete blood count, blood glucose, kidney and liver function, lipid profile and ApoE4 genotype (a susceptibility marker). In 2007–2011, the second assessment was done of 2010 study subjects aged ≥65 years who were still alive. The study provides data on prevalence and incidence of dementia and its risk factors, and of related conditions that affect the health of older adults. It also contributes valuable experiences from field work and interactions with older adults and their families. Building on lessons learned, a third assessment to be done in 2016–2018 will incorporate a community intervention strategy to respond to diseases and conditions that predispose to dementia, frailty and dependency in older adults.

KEYWORDS Dementia, Alzheimer disease, chronic disease, aging, chronic illness, frailty, dependency, cohort studies, Cuba

INTRODUCCIÓN Con el envejecimiento poblacional se incrementa el número de personas con enfermedades crónicas, discapacidad, fragilidad y dependencia. Es importante el estudio de la fragilidad —un síndrome clínico que se asocia al incremento del riesgo de caídas, discapacidad, hospitalización, institucionalización y muerte— para mejorar la práctica clínica y los indicadores de salud de la población.

OBJETIVOS Estimar la prevalencia de la fragilidad y sus factores de riesgo, determinar la incidencia de la dependencia, estimar el riesgo de mortalidad e identificar los factores predictores de la muerte en una cohorte de adultos mayores en las provincias de La Habana y Matanzas, en Cuba.

MÉTODOS Se realizó un estudio longitudinal prospectivo de puerta en puerta entre junio de 2003 y julio de 2011, para lo cual se empleó una cohorte de 2 813 adultos de 65 o más años provenientes de los municipios seleccionados de las provincias de La Habana y Matanzas; el seguimiento promedio fue de 4.1 años. Las variables independientes incluyeron aspectos demográficos, factores conductuales de riesgo e indicadores socioeconómicos, enfermedades crónicas no transmisibles (hipertensión, ictus, demencia, depresión, diabetes, anemia), el número de comorbilidades, y el genotipo APOE ε4. Las variables dependientes fueron: fragilidad, dependencia y mortalidad. Los criterios de fragilidad fueron: lenta velocidad de desplazamiento, agotamiento, pérdida de peso, poca actividad física y declinación cognitiva. Se estimaron la prevalencia y el riesgo de fragilidad mediante la regresión de Poisson, a la vez que la dependencia y los riesgos de mortalidad y sus pronosticadores se determinaron mediante la regresión de Cox.

RESULTADOS El síndrome de fragilidad tuvo una prevalencia de 21.6% (IC 17.9%–23.8%) en la población estudiada, y se asoció positivamente con la edad avanzada, la anemia y la presencia de comorbilidades (ictus, demencia, depresión, y tres o más enfermedades físicas limitantes). La prevalencia de fragilidad estuvo inversamente asociada con: la pertenencia al sexo masculino, tener mayor nivel educacional, estar casado o tener pareja y contar con mayor número de bienes y servicios en el hogar.

La incidencia de dependencia durante el seguimiento fue de 33.1 por 1 000 personas por año (IC 29.1–37.6) y la mortalidad fue de 55.1 por 1 000 personas por año. El mayor riesgo de muerte se asoció con: la edad avanzada, pertenecer al sexo masculino, tener menor posición ocupacional durante los años productivos, la dependencia, la fragilidad, la demencia, la depresión, el ictus y la diabetes.

CONCLUSIONES Debido al desafío que representan las transiciones demográfica y epidemiológica para los países en desarrollo, expresado en la alta prevalencia de la fragilidad, la dependencia y las enfermedades crónicas no transmisibles en los adultos mayores, así como por la asociación de todo lo anterior con una mayor mortalidad, es necesario que la atención se centre en los adultos mayores como grupo de riesgo. Esto debe abarcar una mayor protección social, servicios de salud adecuados según la edad y la modificación y el control de factores de riesgo cardiovasculares.

PALABRAS CLAVE Fragilidad del anciano, fragilidad de los adultos mayores, edad avanzada, ancianos, dependencia, mortalidad, enfermedades crónicas, demencia, enfermedad de Alzheimer, factores de riesgo, mama, sistema reproductor femenino, fertilidad, Cuba

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.

KEYWORDS Frail elderly, frail older adults, aged, elderly, dependency, mortality, chronic disease, dementia, Alzheimer disease, risk factors, Cuba

The following error has been corrected in all online versions of this article. 

Page 24, Introduction, first paragraph, line 2, “600,000 to 2 billion” should read “600 million to 2 billion.”

Introduction: Cerebrovascular disease (CVD) is the third cause of death and second cause of disability and dementia in adults aged ≥65 years worldwide. The few epidemiological studies of stroke in Latin America generally report lower prevalence and different patterns than developed countries.

Objective: Estimate the prevalence of stroke and associated risk factors in adults aged ≥65 years in Havana City and Matanzas provinces, Cuba.

Methods: Single phase, cross-sectional, door-to-door study of 3015 adults aged ≥65 years in selected municipalities of Havana City and Matanzas provinces. Variables studied were age, sex, educational level, and self-report and description of chronic disease (stroke, heart attack, angina, and diabetes mellitus), substance use (alcohol, tobacco), and dietary habits. Respondents were given a structured physical and neurological exam, and blood pressure was measured. Laboratory tests comprised complete blood count, fasting glucose, total cholesterol and fractions, triglycerides, and apolipoprotein E (APOE) genotype. Diagnosis of stroke was based on the World Health Organization’s definition. Stroke prevalence ratios (crude and adjusted), with 95% confidence intervals (CI), were calculated for the variables studied using a Poisson regression model. Risk association was analyzed using multiple logistic regression for dichotomous responses.

Results: Assessments were made of 2944 older adults (97.6% response rate). Prevalence of stroke was 7.8% (95% CI 6.9–8.8), and was higher in men. The risk profile for this population group included history of hypertension (OR 2.8; 95% CI 2.0–4.0), low HDL cholesterol (OR 2.6; 95% CI 1.7–3.9), male sex (OR 1.7; 95% CI 1.2–2.5), anemia (OR 1.6; 95% CI 1.1–2.5), history of ischemic heart disease (OR 1.5; 95% CI 1.0–2.3), carrier of one or two apolipoprotein E4 genotype (APOE ε4) alleles (OR 1.4; 95% CI 1.0–2.0), and advanced age (OR 1.3; 95% CI 1.1–1.9).

Conclusions: Stroke prevalence in this study is similar to that reported for Europe and North America, and higher than that observed in other Latin American countries. The risk profile identified includes classic risk factors plus anemia and APOE ε4 genotype.

Keywords: Apolipoprotein E4, population-based study, epidemiology, risk factors, stroke, prevalence, Cuba