External validation of a clinical pharmacy intervention in geriatric inpatients: a controlled study

Background Clinical pharmacist interventions have been shown to improve drug use in older adults. Study findings are seldom externally validated however. Objective First, to validate a minimized iteration of a previously tested intervention of clinical pharmacists in a non-academic setting with limited staffing resources. Second, to compare the potentially inappropriate medication (PIM) reduction to two previous controlled interventional studies. Methods A controlled study was performed at geriatric wards. The control group received usual care. The intervention group was exposed to a clinical pharmacist led medication review, based on the use of the RASP list, (the Rationalization of Home Medication by an Adjusted STOPP list in Older Patients). Drug use on admission and at discharge were evaluated, including the number of RASP-identified potentially inappropriate medications (PIMs). The PIM reduction was compared to two previous controlled study findings using a linear mixed model. Results Drug use declined during hospital stay, without differences between control (n = 29) and intervention group (n = 32). Antidepressants and hypnotic drugs were discontinued more frequently in IG patients. More PIMs were reduced in the intervention patients (control vs. intervention: 1.0 vs. 3.0, p < 0.001). Across three controlled studies, a robust reduction of 1.56 PIMs (95% confidence interval 1.10-2.02, p < 0.001) was observed in favor of the CP interventions. Conclusion The minimal CP intervention resulted in fewer RASP PIMs. No net reduction of drug use was observed, yet fewer antidepressants and hypnotic drugs were used. The RASP PIM reduction was comparable to previous investigations.