Funcionalidade em idosos e sua relação coma a atividade física e o comportamento sedentário

Abstract

Disability is negatively associated with health in older adults, and its prevention can be achieved by maintaining healthy behaviors throughout life. In this sense, understanding the interrelationships between sedentary behavior (SB), physical activity (PA) and disability, may help in the implementation of more assertive health actions. Thus, the objective of this study was to estimate the prevalence of disability in older adults and to verify their interrelationship with PA and SB. To this end, two studies were performed. The first aimed to estimate the prevalence of disability for Brazilian community-dwelling older adults through a systematic review with meta-analysis of the existent literature. The second study was a cross-sectional study, with the objectives of 1) identifying the prevalence of disability for basic activities (BADL) and instrumental of daily living (IADL) and their associated factors in older adults; 2) to investigate the relationship between PA and SB with disability in BADL and IADL in older adults and their possible mediators; and 3) to verify the impact of isotemporal substitution of SB, sleep time and PA on disability for BADL and IADL in older adults. For the systematic review, we searched the electronic databases Medline (via PubMed), SciELO, Web of Science, Scopus e CINAHL. The cross-sectional study was conducted with older adults enrolled in the Family Health Strategy and living in the urban area of the city of Alcobaça, State of Bahia. Participants answered an interview-based questionnaire, containing questions on sociodemographic, health and behavioral issues. The prevalence of disability in Brazil, according to the meta-analysis, was 19.0% (95%CI: 16.0-22.0, I2 = 99.1%) for BADL and 43.0% (95%CI: 36.0-50.0, I2 = 98.9%) for IADL. In Alcobaça, BA, prevalences were 21.2% for BADL and 69.5% for IADL. Sociodemographic, health, PA and SB factors were associated to disability in BADL and IADL. PA was directly and indirectly associated with IADL. The indirect association was mediated by self-esteem, aerobic endurance, agility/balance. SB had an indirect association with AIVD, being mediated by aerobic endurance, nutritional status and agility/balance. In relation to BADL, PA presented an indirect association mediated by aerobic endurance and IADL. The association of SB with BADL was mediated by aerobic endurance and lower body flexibility. The isotemporal replacement analysis indicated that reallocation of time spent in sleep or SB for the same amount of time in moderate to vigorous PA resulted in a lower probability of disability for BADL and IADL.The results of the present study made it possible to understand the relationship of PA and SB with disability, indicating the need for strategies to reduce the prevalence of disability in older adults and the importance of PA in this process. It should be emphasized that intervention strategies based on the reduction of SB and increase of PA should consider the effects of the mediating variables.