Disability in relation to basic and instrumental activities of daily living among elderly subjects

Objective: To assess the prevalence of disability and associated factors in elderly, by focusing on basic and instrumental activities of daily living. Methods: This was a cross-sectional study on 598 subjects aged 60 years or over who were selected through two-stage cluster sampling in Pelotas, Southern Brazil, between 2007 and 2008. Basic and instrumental activities were evaluated using the Katz Index and the Lawton Scale, respectively. Disability relating to each domain was defined as the need for partial or total assistance to perform at least one activity of daily living. Poisson regression with robust variance was used in the crude and adjusted analyses, taking the cluster sampling into account. Results: The prevalence of disability relating to basic activities was 26.8% (95% CI: 23.0; 30.8). The lowest proportion of independence was in relation to controlling the urination and/or evacuation functions. In relation to instrumental activities, the prevalence of disability was 28.8% (95% CI: 24.5; 33.1), particularly in relation to moving around using means of transportation. A high proportion of the elderly subjects (21.7%) presented more than one instrumental activity with disability. In relation to basic activities, the greatest proportion presented dependence for only one activity (16.6%). In the adjusted analysis, disability relating to basic activities was associated with non-white skin color (p=0.01) and increasing age (p<0.001). Disability relating to instrumental activities was only associated with increasing age (p<0.001). Conclusions: The association between disability relating to basic and instrumental activities and increasing age is an indicator of importance for enabling the health services to plan actions that aim to prevent or delay the occurrence of disability, thereby ensuring independence and better quality of life among the elderly.