Polypharmacy in older patients at primary care units in Brazil

Background Despite extensive studies of polypharmacy in older patients, no consensus regarding the definition of this practice exists in the literature. Several studies have defined polypharmacy as problematic when considering only the numbers of medications used by patients. Objective This study aimed to assess the prevalence of polypharmacy prescribing by comparing two different definitions (quantitative and qualitative) and evaluating factors associated with this practice in older patients. Setting Twenty-three basic health units. Method A cross-sectional study involving 386 older adults who received a prescription after a medical consultation. Multivariate analyses were conducted using a Poisson regression with robust variance. Main outcome measure The main outcome measures included patients with a prescription of five or more medications (quantitative polypharmacy) and those with a prescription of five or more medications including at least one drug considered potentially inappropriate for older adults (qualitative polypharmacy). Results The frequency of quantitative polypharmacy was 20.5%. The results of an adjusted analysis showed that the frequency of quantitative polypharmacy was associated with a higher number of self-reported morbidities and the prescription of potentially inappropriate drugs. The prevalence of qualitative polypharmacy was 10.4%, and after adjustment, this outcome remained significantly associated with the presence of three or more self-reported morbidities. Conclusions The presence of multiple comorbidities was identified as the main factor associated with the prescription of both quantitative and qualitative polypharmacy.