RESUMO
BACKGROUND: Polypharmacy may result from inappropriate prescribing of medications to treat adverse drug reactions (ADRs), i.e., "prescribing cascade." A potentially harmful prescribing cascade affecting those with severe dementia can result when anticholinergics are prescribed to manage side effects of cholinesterase inhibitors (ChEIs). We investigated 1) factors associated with co-prescribing of anticholinergics and ChEIs and 2) whether discontinuation of ChEIs was associated with subsequent discontinuation of anticholinergics-a potentially beneficial reversal or "deprescribing cascade." METHODS: We conducted a retrospective analysis of linked Medicare Part A/B/D claims, Master Beneficiary Summary File, Minimum Data Set, Area Health Resource File, and Nursing Home Compare from 2015 to 2016. Subjects were Medicare beneficiaries residing in nursing homes, ≥65 years old with severe dementia admitted for non-skilled stays, who were prescribed ChEIs. Cross-sectional analysis evaluated factors associated with co-prescribing of anticholinergics with ChEIs. Longitudinal Cox proportional hazards regression examined whether discontinuation of ChEIs was associated with subsequent discontinuation of anticholinergics over a 1-year period. RESULTS: We found 15% of our sample experienced co-prescribing of anticholinergics and ChEIs. Several resident and facility-level factors were associated with co-prescribing anticholinergics. Advancing age, minority race or ethnicity, end-stage renal disease, heart failure, and poor appetite were associated with a decreased likelihood of co-prescribing. Female sex, polypharmacy, and non-geriatric prescriber-type were associated with a higher likelihood of co-prescribing. In longitudinal analyses, we observed that discontinuation of ChEIs was associated with a reduced likelihood (HR 0.58 [95% CI, 0.47-0.71]) of discontinuing any medications with anticholinergic properties, except for bladder antimuscarinics (HR 1.32 [95% CI, 0.83-2.09]). CONCLUSIONS: Younger, healthier older adults with dementia were more likely to experience co-prescribing anticholinergics and ChEIs. Discontinuation of anticholinergics was infrequent. Further research is needed to understand prescribers' ability to recognize and reverse potential prescribing cascades through deprescribing.