Human immunodeficiency virus and tuberculosis coinfection prevalence and treatment outcomes in Cameroon: a systematic review and meta-analysis

Background: Human immunodeficiency virus (HIV) and tuberculosis (TB) form one of the deadliest syndemics, and sub-Saharan Africa bears over 80% of HIV-associated TB deaths. In Cameroon, evidence on HIV/TB coinfection remains unsynthesized across regions and populations, obscuring the national burden. Hence, we estimated the prevalence of HIV/TB coinfection and treatment outcomes in Cameroon. Methods: Following PRISMA 2020 (PROSPERO: CRD420261399169), we searched PubMed, Scopus, Embase, Web of Science, Cochrane Library, African Journals Online, and grey literature for English- and French-language studies conducted in Cameroon. Reports were independently screened, their data extracted, and their methodology appraised using Joanna Briggs Institute tools. Random-effects models pooled prevalence, treatment outcomes, and adjusted odds ratios. Heterogeneity was assessed with I2. Results: Seventy studies (1995-2023) were included, 87.1% at low risk of bias. Pooled HIV prevalence among TB patients was 29.2% (95% CI: 26.3-32.3; 67 studies; n=57,169; I2 = 97.8%), with no significant evidence of publication bias. Prevalence was higher from 2007 onwards (29.9%; 62 studies; n=55,358) than before (20.5%; 5 studies; n=1,811). It was highest in the North-West (41.9%; 7 studies; n=6,324) versus Littoral (25.0%; 15 studies; n=10,419) and West (23.8%; 6 studies; n=4,206); and in extrapulmonary TB (42.3%; 3 studies; n=371) versus mixed forms (37.7%; 21 studies; n=37,239) and pulmonary TB (23.9%; 37 studies; n=16,096) (all p<0.05). Among coinfected patients, pooled treatment success was 75.9% (95% CI: 70.4-80.8; 8 studies; n=4,230), mortality 21.1% (95% CI: 11.9-34.7; 10 studies; n=4,403), loss to follow-up 7.7% (95% CI: 4.3-13.3; 5 studies; n=3,103), and treatment failure 0.3% (95% CI: 0.1-1.5; 6 studies; n=3,520). Lack of antiretroviral therapy (ART) increased the odds of unfavorable outcomes (AOR = 1.90; 95% CI: 1.15-3.12; 2 studies). Conclusions: Approximately three in ten TB patients in Cameroon are coinfected with HIV, with marked regional and clinical variation. Treatment success remains below national targets. Strengthening TB-HIV service integration, routine HIV testing, and timely ART initiation and continuation is essential to reduce the HIV-associated TB morbidity and mortality in the country.