Prevalence of sickle cell disease and sickle cell traits among children and adolescents in Nigeria: a systematic review and meta-analysis

Abstract

Sickle cell disease (SCD) is one of the most common genetic disorders in the world, with Nigeria believed to have the highest burden. Despite the high burden in the country, the true prevalence of SCD and its main driver—the sickle cell trait (SCT)—is unknown, which is important for planning and resource allocation. Hence, we conducted a systematic review and meta-analysis of the prevalence of SCD, SCT, and associated factors in Nigerian children and adolescents. Using the PRISMA guidelines [ID: CRD42024556354], we systematically search the following major databases: AJOL, Google Scholar, PubMed, EMBASE, Cochrane Library, Scopus, and Web of Science collections from January 1950 to October 2024 on Nigerian children and adolescents with SCD and/or SCT. The quality of the studies was assessed using the Newcastle–Ottawa Scale adapted for cross-sectional studies. We performed a cumulative meta-analysis to estimate the pooled prevalence and associated factors for SCD and SCT. Thirty studies, comprising 211,938 participants, were included in the final analysis after stepwise screening. The pooled prevalences of SCD and SCT were 4.0% (95% CI 3.0 to 6.0, I 2 = 99.6%) and 21.0% (95% CI 20.0 to 23.0, I 2 = 90.5%), respectively. The northwestern geopolitical zone had the highest pooled prevalence of SCD (7.0%; 95% CI 3.0 to 11.0; I 2 = 98.9% ) and SCT (23.0%; 95% CI 19.0 to 28.0%, I 2 = 54.2%). The southeastern region had the lowest pooled prevalence of SCD (2.0%, 95% CI 0.3 to 3.0%, I 2 = 96.5), whereas the southwestern region had the lowest pooled prevalence of SCT (19.0%, 95% CI 14.0 to 25.0%, I 2 = 92.2). There was no relationship between sex, socioeconomic status, and SCD. The pooled prevalence of SCD and SCT among children and adolescents was high, with the highest burden occurring in the northwestern geopolitical zone in Nigeria. In addition, there was no relationship between sex, socioeconomic class, and prevalence of SCD. PROSPERO ID: CRD42024556354.