Associações entre comportamentos de movimento de 24 horas e o declínio cognitivo em idosos

Abstract

With the increase in the number of elderly people in Brazil and the consequences of cognitive decline in this population group, knowledge of the prevalence and the effect of different behaviors on cognitive responses can contribute to the prevention, reduction and protection of the disease. Thus, two surveys were carried out: 1) a systematic review and meta-analysis to estimate the prevalence of cognitive decline in elderly Brazilians; 2) verify the hypothetical effects of replacing sedentary behavior with an equivalent amount of physical activity from different domains on cognitive decline in an elderly population in the community. For the systematic review, the electronic databases Medline (via PubMed) and Lilacs were searched and studies with elderly Brazilians who identified the prevalence of cognitive decline were selected. Meta-analysis was performed to estimate cognitive decline using a random effect model. The heterogeneity of the results was assessed by the chi-square test (significance at p <0.10), while the magnitude of the effects was quantified by I2. The second study was carried out with 473 elderly people registered in the Family Health Strategy and living in the urban area of the municipality of Alcobaça, BA. The elderly who met the inclusion criteria of the study were informed about the objective of the research and gave their consent to participate, answered a questionnaire structured in the form of an interview. Cognitive decline was assessed by the Mine Mental State Examination. For data analysis, isotemporal replacement models were built in Poisson Regression models. According to the meta-analysis, the estimated prevalence of cognitive decline in elderly Brazilians was 28.0% (95% CI: 24.0 - 33.0; I2 = 98.5%). In the analysis of isotemporal models, it was found that the substitution of time spent sitting, transportation and sleep for the same time in physical activity during leisure time can have a protective factor against cognitive decline. The results of the present study indicate the need for intervention strategies to reduce the prevalence of cognitive decline. When considering interventions related to leisure-time physical activity and the reduction of sedentary behavior to minimize the deleterious effects of cognitive aging, factors of physical activity in transportation and sleep must be taken into account.