Assessing the Burden and Predictors of Drug-Related Hospital Admissions at a Tertiary Hospital in Enugu, South East Nigeria

Drug-related hospital admissions represent preventable failures of medication management and impose significant burdens on hospital resources and patient health. Understanding their burden and predictors is essential for designing targeted pharmacist-led prevention programs. This study assessed the prevalence, characteristics, and predictors of drug-related admissions at a tertiary hospital in Enugu, South East Nigeria. A prospective observational study was conducted over six months in the emergency and internal medicine wards. Admissions were classified as drug-related using a validated algorithm incorporating the Hallas criteria, and causality was assessed using the WHO-Uppsala Monitoring Centre scale. Of 1,240 admissions reviewed, 18.3 percent were classified as drug-related. Non-adherence accounted for 31 percent of drug-related admissions, followed by adverse drug reactions at 27 percent, drug interactions at 19 percent, and inappropriate drug use at 16 percent. Antihypertensives, antiretrovirals, and antidiabetics were the drug classes most frequently implicated. Independent predictors of drug-related admission included polypharmacy, previous drug-related hospitalization, age above 65, absence of pharmacist follow-up, and low health literacy. Economic analysis estimated the additional cost per drug-related admission at approximately 85,000 naira beyond standard care costs. These findings highlight the substantial and preventable burden of drug-related admissions and support investment in pharmacist-led medication management programs within the hospital. Keywords: drug-related admissions, adverse drug reactions, non-adherence, Enugu, hospital pharmacy