Substitution Patterns After Discontinuation of CNS ‐Active Medications in Older Adults in Primary Care

BACKGROUND: Little is known about substitution of alternative medications in the context of deprescribing. The objectives were to: (1) determine the frequency of medication substitutions among those who discontinued a central nervous system (CNS)-active medication, and (2) characterize substitutions as potentially inappropriate (as per the 2023 Beers Criteria) versus not. METHODS: We conducted a secondary analysis that combined data from the intervention and usual care arms from the STOP-FALLS deprescribing trial that tested a health-system-embedded intervention designed to reduce prescription of CNS-active medications. This analysis focused on participants followed for 360 days following baseline with chronic use of opioids, benzodiazepines, tricyclic antidepressants, skeletal muscle relaxants, or Z-drugs. Discontinuation was defined as the first date when there was no evidence of a prescription fill for 90 days, thus only participants with a discontinuation that occurred in the first 270 days were included. A list of likely alternative treatments was developed for each target medication. A substitution was operationalized as a new alternative medication prescribed during the 30 days prior to or 60 days after discontinuation of a target medication. RESULTS: The study sample included 2182 individuals (average age 70.5 years, 63.1% female). At baseline, a total of 2415 target medications were prescribed, of which 442 (18.3%) were discontinued. Discontinuation rates varied from 122 (8.0%) for users of opioids to 86 (49.7%) for users of skeletal muscle relaxants. Substitutions were made for 42 (9.5%) drug discontinuations. Of these substitutions, 11 of 42 (26.2%) were to a potentially inappropriate medication: tricyclic antidepressants (n = 5), benzodiazepines (n = 3) and hydroxyzine (n = 3). Other common substitutions included gabapentin, selective serotonin norepinephrine reuptake inhibitors, and trazodone. DISCUSSION: Of medication discontinuations with a substitution, one-quarter were to at least one potentially inappropriate medication. This finding highlights the need for additional guidance for prescribers to ensure safe deprescribing of CNS-active medications.