The prevalence and social patterning of chronic diseases among older people in a population undergoing health transition. A 10/66 Group cross-sectional population-based survey in the Dominican Republic

Background: Very little of the increased attention towards chronic diseases in countries with low and middle incomes has been directed towards older people, who contribute 72% of all deaths, and 14% of all Disability Adjusted Life Years linked to this group of conditions in those regions. We aimed to study the prevalence of physical, mental and cognitive diseases and impairments among older people in the Dominican Republic, their social patterning, and their relative contributions to disability. Methods: A cross-sectional catchment area one-phase survey of chronic disease diagnoses, physical impairments, risk factors and associated disability among 2011 people aged 65 years and over (of whom 1451 gave fasting blood samples) in Santo Domingo, Dominican Republic. Results: The most prevalent diagnoses were hypertension (73.0%), anaemia (35.0%), diabetes (17.5%), depression (13.8%) and dementia (11.7%), with 39.6% meeting criteria for metabolic syndrome. After direct standardization (for age and sex) the prevalences of stroke (standardized morbidity ratio [SMR] 100) and hypertension (SMR 108) were similar to those in the United States of America National Health and Nutrition Examination Survey (NHANES reference SMR 100), while those of diabetes (SMR 83) and metabolic syndrome (SMR 72) were somewhat lower. Anaemia was three times more common than in the USA (SMR 310). Diabetes, hypertension, dyslipidaemia, obesity and the metabolic syndrome were associated with affluence and female sex. Arthritis, anaemia, dementia and stroke were strongly age-associated and these conditions were also the main independent contributors to disability. Conclusions: The prevalence of many chronic diseases is similar in predominately low socioeconomic status neighbourhoods in the Dominican Republic to that in the USA. Prevalence of age-associated conditions is likely to increase with demographic ageing. There is also scope for increases in cardiovascular disease prevalence, if, as observed in other settings undergoing the epidemiologic transition, the burden of risk factors shifts towards the less affluent. Monitoring future trends in the prevalence and social patterning of chronic diseases may help to assess the effectiveness and equity of primary and secondary prevention strategies. Specific recommendations from our research include identifying and targeting the causes of anaemia among older people, and addressing women's health disadvantages.