The Bambui health and ageing study (BHAS): methodological approach and preliminary results of a population-based cohort study of the elderly in Brazil

Objective A cohort study has been designed to identify predictors of adverse health e vents in the elderly. The methodology of the study and preliminary descript ive results are presented. Methods The study population comprises all residents of Bambui (Minas Gerais, Brazi l), aged 60 or more years (n=1.742). From these, 92.2% were interviewed and 85.9% underwent clinical examination, consisting of haematological and bio chemical tests, serology for Trypanosoma cruzi, anthropometric and blood pr essure measures and electrocardiogram. Aliquots of serum, plasma and DNA we re stored for future investigations. The baseline interview included sociod emographic characteristics, self-referred health condition and history of s elected diseases, medication use, health service use, source of medical car e, physical activities, smoking, drinking and eating habits, reproductive h istory, physical functioning, life events, social support and mental health . Individuals are being followed up annually. Results The following characteristics predominated among participants: women (60,0% ), married (48.9%) or widowed (35.4%), people living in households with up to 2 residents (73.8%), heads of family (76.7%), people with monthly income between 1.00 and 2.99 Brazilian minimum wages (62.0%) and people with up t o 4 years of schooling (89.1%). The median age was 68 years. Among the coho rt members, only 1.7% were lost in the first follow-up. Conclusions In general, the characteristics of the study population were very similar t o those from other epidemiological studies of the elderly based on large Br azilian cities. The small number of losses to follow-up indicates that the choice of Bambui was adequate, assuring the feasibility of a long term coho rt study.