OBJECTIVE: To evaluate the prevalence of polypharmacy and the influence of income on the association between medication use and cognitive impairment among elderly people. METHODS: Out of the 1,606 baseline members of the Bambuí cohort of elderly people, which started in 1997, 1,554 took part in the study. The Mini-Mental State Examination was applied to all the participants. The association between cognitive impairment and polypharmacy was tested by means of multivariate ordinal regression, performed for the whole population and for each of the income strata. RESULTS: The prevalence of polypharmacy (two or more medications consumed) was 70.4% and the number of medications used presented an independent negative association with cognitive impairment (OR=0.72; 95% CI: 0.55;0.95). When this was stratified according to personal income (<2 minimum monthly salaries versus > 2 minimum monthly salaries), a negative association was observed between medication use and cognitive impairment among elderly people with lower income (OR=0.64; 95% CI: 0.48;0.86), but not among those with higher income (OR=1.74; 95% CI: 0.81;3.74). CONCLUSIONS: With regard to the association between cognitive impairment and number of medications consumed, the results indicate social inequality in the use of medications. It is possible that these elderly people are not consuming the medicines needed for appropriate treatment of their health problems.
Health of the elderly; Polypharmacy; Pharmacoepidemiology; Drug utilization; Cognitive impairment; Income
