Prevalence and associated factors of Leukemia in Africa: A systematic review and meta-analysis

Leukemia is a group of diverse and biologically distinct blood cancers. While progress has been made in combating infectious diseases, chronic diseases like leukemia are increasingly prevalent. Current data on leukemia's prevalence in Africa are inconsistent, necessitating a comprehensive systematic review. This study aims to determine the pooled prevalence and associated risk factors of leukemia across Africa through a systematic review and meta-analysis.

This systematic review and meta-analysis were conducted based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A comprehensive literature search was conducted across multiple databases, including PubMed/MEDLINE, Scopus, and Science Direct, supplemented by searches using the Google Scholar and manual searches to identify eligible studies. Statistical analysis was performed using STATA version 11, with a random-effects model employed to compute pooled estimates. Higgen's I2 test statistics and meta-regression was conducted to explore potential sources of heterogeneity. Publication bias was assessed visually by Funnel plots and statistically using Egger's weighted regression test, a p-value of less than 0.05 indicates the presence of significant publication bias.

A total of 17,546 articles were retrieved, of which fifteen studies, which recruited 42,884 individuals, were included in the meta-analysis. The pooled prevalence of leukemia was 5.09% (95% CI: 4.02, 6.17) with I2 of 97.1%. Due to the heterogeneity, subgroup analyses by country showed that the highest prevalence was 10.58% in Nigeria, and the lowest was 0.58% in Zambia. Subgroup analysis based on publication year revealed 4.16% among studies conducted before 2015 and 6.67% among studies conducted after 2016. Additionally subgroup by sample size showed: smaller sample sizes (<384 participants) yielded a higher pooled estimate of 7.99%, conversely, studies with larger sample sizes (≥385 participants) showed 3.61%. Whereas subgroup analysis by population showed that 3.38% in children and 7.15% in the general population. Among the factors identified, rural residency (OR: 56.98, 95% CI: 9.97-326.70) and older age (OR: 3.90, 95% CI: 1.39-10.98) were significant predictors of leukemia in Africa.

This review reveals a pooled prevalence of 5.09%, with rural residency and older age identified as significant predictors of leukemia in Africa, underscoring a public health concern.