Prevalence, Predictors, and Clinical Consequences of Potentially Inappropriate Prescribing in Older Adults with Multimorbidity in Ibadan, South West Nigeria

Background: Potentially inappropriate prescribing (PIP) in older adults with multimorbidity is a significant source of preventable drug-related harm globally. In Nigeria, the ageing population and rising burden of non-communicable diseases create an urgent need for geriatric pharmacotherapy research. This study assessed the prevalence, predictors, and clinical consequences of PIP in older multimorbid patients in Ibadan. Methods: A prospective observational study recruited 310 patients aged 65 years and above with three or more concurrent chronic conditions from the medicine outpatient clinic of University College Hospital, Ibadan. PIP was identified using the Beers Criteria (2023 update) and STOPP/START criteria version 3. Multivariate logistic regression identified independent predictors of PIP. Clinical outcomes including falls, hospitalisations, and ADRs were assessed over a six-month follow-up period. Results: PIP was identified in 54 percent of patients using STOPP criteria and 61 percent using Beers Criteria. Polypharmacy (OR 3.4), renal impairment (OR 2.1), and age above 80 years (OR 1.8) were independent predictors. At follow-up, PIP was significantly associated with falls (OR 2.3) and drug-related hospitalisations (OR 2.6). Conclusion: PIP is highly prevalent in older multimorbid patients in Ibadan and is associated with significant adverse outcomes. Structured medication reviews using validated screening tools must be integrated into geriatric outpatient care. Keywords: potentially inappropriate prescribing, older adults, multimorbidity, Beers Criteria, Ibadan