Anticholinergic burden and polypharmacy in primary care referrals to tertiary outpatient clinics in Brazil

Abstract

AbstractBackgroundAnticholinergic burden (ACB) and polypharmacy are associated with cognitive/functional impairment in the elderly and their frequency in primary care has been poorly studied in Brazil. We aimed to evaluate the frequency ACB/polypharmacy and association with cognitive impairment in two large tertiary care outpatients memory clinics in Brazil.MethodsWe retrospectively analyzed records of referrals from primary care to two tertiary outpatients memory clinics in Brazil (Hospital de Clínicas de Porto Alegre (HCPA), Porto Alegre and Hospital Santa Marcelina (HSM), São Paulo) from 2014 to 2022. Sociodemographic, clinical and medications in use in the first appointments were recorded. The ACB was calculated using the Brazilian Anticholinergic Activity Drug (BAAD) score, which classified drugs according to their central anticholinergic activity from 1 to 3, with higher values indicating greater anticholinergic activity. The BAAD score was dichotomized as = 0 or ≥ 1. Polypharmacy was defined as ≥ 5 drugs. A logistic regression was performed using age, sex, education, disease duration, dementia etiology, center and Mini Mental State Examination (MMSE) as covariates.ResultsAmong 980 referrals (HCPA = 429; HSM = 551), 602 (64.9%) had a final diagnosis of dementia, HCPA = 226 (56.1%); HSM = 376 (71.8%); p<0.001. Alzheimer’s disease, 93 (21.7%) and multifactorial dementia, 109 (19.8%), was the most common dementia diagnosis in HCPA and HSM, respectively. Most patients, 666 (74%), had BAAD ≥ 1 and nearly half 438 (48.7%) had polypharmacy, with no difference between centers (Table 1). BAAD was not different between diagnoses, but polypharmacy was more frequent in vascular (71, 63.4%) and multifactorial (82, 59.9%) dementia. BAAD was associated with MMSE (OR 0.95, IC 95% 0.93‐0.97) and polypharmacy (OR 3.71, IC 95% 2.66‐5.24). In addition to BAAD, polypharmacy was also associated with female sex (OR 1.45, IC 95% 1.09‐1.91) and age (OR 1.01, IC 95% 1‐1.02).ConclusionMost patients referred from primary care were using some drug with anticholinergic activity and almost half had polypharmacy, which suggests liberality in the prescription of medications in this context.