Prevalence of potentially inappropriate medication prescribing, inappropriate medication use, prescription omission and drug interactions among older adults in Ethiopia: a systematic review and meta-analysis

Objective To determine the prevalence of potentially inappropriate prescribing (PIP), potentially inappropriate medication (PIM), potential prescription omission (PPO), potentially harmful drug–drug interactions (PDDI) and identify associated factors among older Ethiopians. Design Systematic review and meta-analysis Data source We searched PubMed, HINARI, Scopus and Web of Science databases to identify eligible studies published up to 31 October 2025. Study selection Observational studies reported the prevalence of PIP, PIM, PPO and PDDI among older adults from any healthcare settings were screened. Data extraction and synthesis Two independent reviewers selected studies, extracted data and assessed the risk of bias. The quality and risk of bias of the studies were assessed using the Newcastle-Ottawa scale and Hoy risk of bias tool, respectively, while the certainty of evidence of outcomes was assessed using Grading of Recommendations, Assessment, Development and Evaluation based on Cochrane recommendations. We used a random-effects model for analyses to estimate the pooled prevalence and associated factors. All data analyses were done using Stata V.17 software. Main outcomes and measures The national prevalence of PIP, PIM, PPO and PDDI was estimated as main outcomes. Variations were estimated based on regions, age groups, outcome evaluation tool, disease type and healthcare setting. Results The review included 25 studies (n=5662 participants) for PIP or PIM, 14 studies (n=2706 participants) for PDDI and 6 studies (n=1342 participants) for PPO. The pooled prevalence estimate was 41% (95% CI 33% to 48%), I 2 =96.87% for PIP, 37% (95% CI 31% to 44%), I 2 =96.33% for PIM, 55% (95% CI 36% to 73%), I 2 =99.00% for PDDI and 14% (95% CI 6% to 24%), I 2 =95.07% for PPO. The majority of the studies have very good quality (very good=13, good=1, satisfactory=11 for PIP and PIM; very good=11, satisfactory=3 for PDDI; very good=6 for PPO) and low risk of bias (low risk=18, moderate risk=7 for PIP and PIM; low risk=12, moderate risk=2 for PDDI and low risk=6 for PPO), while all studies for each outcome have low certainty of evidence. Subgroup analyses revealed significant regional and contextual variations. Polypharmacy was significantly associated with PIP (OR=3.72, 95% CI 2.53 to 5.46, p<0.01, I 2 =69.56%), PIM (OR=4.20, 95% CI 2.91 to 6.06, p<0.01, I 2 =57.83%) and PDDI (OR=4.51, 95% CI 3.05 to 6.69, p<0.01, I 2 =0.00%), while hypertension (OR=2.46, 95% CI 1.38 to 4.36, p<0.01 I 2 =0.00%) was associated with PIP. Conclusions and relevance This review found a high prevalence of PIP, PIM, PDDI and PPO among older adults in Ethiopia, with notable heterogeneity across regions. Polypharmacy was associated with PIP, PIM and PDDI, while hypertension showed association with PIP. Despite generally good study quality, the certainty of evidence was low for the included studies due to the cross-sectional design nature, with high heterogeneity. Therefore, these findings should be interpreted cautiously. This study indicates a high burden of inappropriate medication prescribing and its associated factors, underscoring the importance of further robust studies to clarify prescribing practices and associated factors. PROSPERO registration number CRD42024556744.