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. 2025 Mar 14:12:1517162.
doi: 10.3389/fmed.2025.1517162. eCollection 2025.

Anticoagulation quality through time in therapeutic range in Sub-Saharan Africa: a systematic review and meta-analysis

Desalegn Getnet Demsie  1 , Zenaw Debasu Addisu  1 , Chernet Tafere  1 , Kebede Feyisa  1 , Bereket Bahiru  1 , Malede Berihun Yismaw  1 , Getahun Mihret  2 , Abere Tilahun  3 , Desye Gebrie  4 , Derbew Fikadu Berhe  5
Affiliations

Anticoagulation quality through time in therapeutic range in Sub-Saharan Africa: a systematic review and meta-analysis

Desalegn Getnet Demsie et al. Front Med (Lausanne). .

Abstract

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 I 2 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% (I 2 = 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% (I 2 = 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.

Keywords: INR; Sub-Sahara Africa; TTR; anticoagulation; warfarin.

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Conflict of interest statement

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Figures

Figure 1
Figure 1
Preferred reporting items for systematic reviews and meta-analyses (PRISMA).
Figure 2
Figure 2
Funnel plot of therapeutic INR.
Figure 3
Figure 3
Funnel plot of good-TTR.
Figure 4
Figure 4
Sensitivity analysis of therapeutic INR.
Figure 5
Figure 5
Sensitivity analysis of good TTR.
Figure 6
Figure 6
Forest plot of therapeutic INR.
Figure 7
Figure 7
Forest plot of Good TTR.
See this image and copyright information in PMC

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