Dr. Derbew Fikadu Berhe

Background: The quality of anticoagulation with warfarin is often assessed through the time in therapeutic range (TTR). However, achieving optimal TTR and maintaining therapeutic INR levels presents significant challenges in Sub-Saharan Africa. This review aims to summarize the existing evidence on the quality of warfarin anticoagulation among patients in Sub-Saharan Africa. Method: We searched MEDLINE via Ovid, PubMed, Embase via Ovid, and Scopus, and citation analysis from Google Scholar. The review’s primary focus was therapeutic INR and TTR ≥ 65. Meta-analysis was conducted using R version 4.3.3. A mixed-effects meta-regression model was used to examine the influence of moderators, with heterogeneity estimated using I2 and prediction intervals (PI), and publication bias assessed through funnel plots and Egger’s test, with p < 0.05 indicating potential bias. The robustness of pooled proportions was tested using a leave-one-out sensitivity analysis. The preparation of this review adhered to the guidelines outlined in the PRISMA. Results: We identified 15 observational studies for inclusion in this systematic review and meta-analysis. Egger’s test confirmed an absence of publication bias across these studies. Sensitivity analyses showed consistency in individual therapeutic INR (pooled estimate: 0.37; range: 0.37–0.40) and TTR (pooled estimate: 0.16; range: 0.15–0.17), closely aligning with pooled proportions. Meta-analysis of high-quality TTR measurements yielded a pooled prevalence of 17% (I2 = 89%), with study-specific values ranging from 10 to 29% and predicted effect sizes between 0.05 and 0.34. The therapeutic INR was observed at a pooled prevalence of 40% (I2 = 86%; prediction interval: 0.16, 0.67). Conclusion: Warfarin therapy is associated with very low percentage of TTR suggests poor quality of anticoagulation management. Sensitivity analyses confirmed the robustness of these findings.

ABSTRACTBackgroundWarfarin use in Sub‐Saharan Africa is associated with elevated risks of thromboembolic events and bleeding, but precise prevalence estimates are lacking. This systematic review and meta‐analysis aimed to quantify the prevalence of bleeding and thromboembolic events among patients on warfarin in Sub‐Saharan Africa.MethodsComprehensive searches were conducted in MEDLINE via Ovid, PubMed, Embase via Ovid, Scopus, and Google Scholar to identify relevant studies. Primary outcomes included major and minor bleeding events, while thromboembolic events were secondary outcomes. Meta‐analysis was conducted using RStudio version 4.3.3 with the meta and metaprop packages. Proportions were transformed using the Freeman–Tukey double arcsine method, and meta‐regression was performed with the metafor package's escal, rma, and res functions. Publication bias was assessed via funnel plots and Egger's test, with a p value < 0.05 indicating potential bias. Sensitivity analysis was conducted through leave‐one‐out analysis. The review was performed in adherence to PRISMA guidelines.ResultsWe identified 10 observational studies for inclusion in this systematic review and meta‐analysis. Egger's test indicated no publication bias. Meta‐regression analysis showed that moderators (publication year, sample size, setting, and follow‐up duration) did not significantly impact bleeding risk. The pooled prevalence of major and minor bleeding was 18% (95% CI: 0.10–0.27; I2: 96%, prediction interval: 0.00–0.53), with rates ranging from 4% to 46%. Thromboembolic events occurred in 7% of warfarin users (95% CI: 0.01–0.07).ConclusionWarfarin therapy in Sub‐Saharan Africa is associated with considerable bleeding and thromboembolic risks. The robustness of these findings was confirmed through meta‐regression and sensitivity analyses, underscoring the need for improved therapeutic monitoring and safety strategies in this population.