Ageing with Trypanosoma cruzi infection in a community where the transmission has been interrupted: the Bambui Health and Ageing Study (BHAS)

Background The prevalence of Chagas' disease is decreasing in Brazil. Due t o cohort effect, the disease might remain a public health problem for some time among older individuals. The present burden of Trypanosoma cruzi infec tion for the elderly living in areas where the transmission has been interr upted has not been studied. Methods The prevalence of T cruzi infection and its association with indica tors of health status and health services use were assessed among the elder ly living in one of the oldest endemic areas in Brazil (Bambui, MG). Seropo sitivity was determined by blood tests (IHA and ELISA) performed in 85.6% o f all residents aged 60+ (1496/1742) and in 83.1% of sampled residents aged 5-59 years (1212/1458). Results Seropositivity showed a cohort effect, with no cases below 20 years and high prevalence among those aged 60+ years (37.7%). After adjustment f or confounders, seropositivity was associated with self-rated health reason able (OR = 1.43; 95% CI: 1.03-1.98) and bad/very bad (OR = 1.89; 95% CI: 1. 30-2.75), staying in bed in past 2 weeks (OR = 1.88; 95% CI: 1.21-2.92), ho spitalization in past 12 months (OR = 1.41; 95% CI: 1.05-1.89) and use of 5 + prescribed medications in past 3 months (OR = 1.75; 95% CI: 1.15-2.59). Implications Our results are an example of how survival of individuals with past exposure to infectious disease may lead to a different picture of age ing in the developing world. Policy makers need to consider the extra burde n imposed by increasing rates of non-infectious disease among the elderly ( as observed in Brazil) including the consequences of T cruzi infection in a reas where the infection was widespread in the past.