Use of drugs with anticholinergic activity in outpatients with multiple myeloma: associated factors and agreement between measurement scales

Objective: to determine frequency and factors associated with anticholinergic drugs (DAch) use in patients with multiple myeloma (MM) and analyse the agreement between three anticholinergic scales in classification and categorization of anticholinergic burden. Methods: it was carried out a cross-sectional study with MM outpatients in different services in a state capital city in Brazil. Anticholinergic activity was identified by Brazilian Anticholinergic Activity Drug Scale (BAADS), Anticholinergic Cognitive Burden Scale (ACB), and Anticholinergic Risk Scale (ARS). Multiple logistic regression was performed to identify associated factors. Agreement between scales in classification and categorization of anticholinergic burden determined by Fleiss Kappa and weighted Kappa, respectively. Results: 213 patients with MM were included, median age was 67.2 years. The median number of drugs used was 6 (IQR=6; min=1 and max=19), and approximately 153 (72%) of the patients used polypharmacy. It was identified 56 drugs used with anticholinergic activity. The most used DAch were antidepressants, antipsychotics, and opioids. Frequency of DAch use ranged from 12.7% to 70%. Low agreement was observed in the classification of DAch (k= 0.144). Between BAADS and ACB there is moderate agreement in the classification of cumulative anticholinergic burden (k=0.562; agreement=66.2%). Use of DAch was associated with polypharmacy, according to the three scales. Conclusion: Frequency of DAch use was high, according to BAADS and ACB scales, and positively associated with polypharmacy. There is low agreement classification of DAch and moderate agreement in categorization of anticholinergic burden. Future research should investigate the impact of DAch in clinical outcomes, benefits of anticholinergic deprescribing and criteria to determine DAch score.