Impact of Pharmacist-Led Interventions on Patient Outcomes in Gulf Cooperation Council Countries: A Systematic Review...

Pharmacist-led interventions in Gulf Cooperation Council (GCC) countries have been increasingly studied, yet their overall effectiveness across clinical and healthcare outcomes remains incompletely defined. To address this gap, a systematic review and meta-analysis of randomized controlled trials and quasi-experimental studies published between 2000 and 2025 was conducted, following PRISMA 2020 and Cochrane standards.

Searches of PubMed/MEDLINE, Scopus, Web of Science, and CENTRAL identified 437 records, of which 20 studies met the inclusion criteria; 13 contributed meta-analyzable data as randomized controlled trials and seven as quasi-experimental studies.

Pooled random-effects estimates favored pharmacist-led care for HbA1c, fasting glucose, low-density lipoprotein cholesterol, diastolic blood pressure, and medication knowledge, although these estimates carried substantial, largely unexplained heterogeneity and were rated as low to very low certainty under GRADE. The effects on systolic blood pressure, total cholesterol, triglycerides, high-density lipoprotein cholesterol, unplanned healthcare use, and antimicrobial utilization were favorable but not statistically significant. Quasi-experimental studies consistently demonstrated reductions in mortality and readmissions, though hospital and ICU length of stay remained variable. Risk of bias was judged as some concerns for randomized trials and moderate to serious for quasi-experimental studies, with substantial heterogeneity observed across blood pressure and lipid outcomes.

Overall, pharmacist-led interventions in GCC settings were associated with improvements in glycemic control and LDL cholesterol, with additional benefits in mortality and readmissions, although the certainty of evidence was low to very low, owing to substantial heterogeneity and the predominance of non-randomized designs for the inpatient outcomes. These findings underscore the need for standardized intervention models and outcome measures.