Factors associated with instrumental activities of daily living dependence in the elderly: a case-control study

The main goal of the study was to determine the factors associated with dependence to perform instrumental activities of daily living in the elderly. A population-based case-control study was conducted, with 180 elderly people from Passo Fundo-RS, 2014. The cases were represented by 60 individuals aged ≥ 60 years, dependents to perform instrumental activities of daily living residents of the urban area of the city. The controls were represented by 120 individuals, not dependents to perform instrumental activities of daily living, residents of the urban area of the city. Crude and multivariate analysis using Poisson regression were performed to test the association between the outcome and the independent variables, estimating the crude and adjusted odds ratios (OR) and calculating the 95% confidence intervals respectively. All the variables with p ≤ 0.20 were included in the final model. Remained statistically significant after adjusted analysis: being aged 80 years or more (OR = 1.76; CI95%: 1.01-3.08), having studied from 1 to 4 years (OR = 2.36; CI95%: 1.35-4.14), being illiterate (OR = 2.98; CI95%: 1.52-5.84), having Parkinson's disease (OR = 2.44; CI95%: 1.39-4.29) and the presence of cognitive impairment (OR = 1.88; CI95%: 1.30-2.72).