Estimate of the incidence of bladder cancer in Africa: A systematic review and Bayesian meta-analysis

To quantify the epidemiology of bladder cancer in Africa to guide a targeted public health response and support research initiatives.

We systematically searched publicly available sources for population-based registry studies reporting the incidence of bladder cancer in Africa between January 1980 and June 2017. Crude incidence rates of bladder cancer were extracted. A Bayesian network meta-analysis model was used to estimate incidence rates.

The search returned 1328 studies. A total of 22 studies carried out across 15 African countries met our pre-defined selection criteria. Heterogeneity across studies was high (I2  = 98.9%, P < 0.001). The pooled incidence of bladder cancer in Africa was 7.0 (95% credible interval 5.8-8.3) per 100 000 population in men and 1.8 (95% credible interval 1.2-2.6) per 100 000 in women. The incidence of bladder cancer was consistently higher in North Africa in both sexes. Among men, we estimated a pooled incidence of 10.1 (95% credible interval 7.9-11.9) per 100 000 in North Africa and 5.0 (95% credible interval 3.8-6.6) per 100 000 in sub-Saharan Africa. In women, the pooled incidence was 2.0 (95% credible interval 1.0-3.0) per 100 000 and 1.5 (95% credible interval 0.9-2.0) per 100 000 in North Africa and sub-Saharan Africa, respectively. Incidence rates increased significantly among men from 5.6 (95% credible interval 4.2-7.2) in the 1990s to 8.5 (95% credible interval 6.9-10.1) per 100 000 in 2010.

The present study suggests a growing incidence of bladder cancer in Africa in recent years, particularly among men and in North Africa. This study also highlights the lack of quality data sources and collection of essential clinical and epidemiological data in several African countries, and this hinders public health planning.

International journal of urology : official journal of the Japanese Urological Association. 2018 Oct 21 [Epub ahead of print]

Davies Adeloye, Michael O Harhay, Olayemi O Ayepola, Jhonathan Pr Dos Santos, Rotimi A David, Olubanke O Ogunlana, Muktar Gadanya, Victor C Osamor, Ann O Amuta, Emeka E Iweala, Asa Auta, Timothy R Rebbeck

Centre for Global Health Research, Usher Institute of Population Health Sciences and Informatics, The University of Edinburgh, Edinburgh, UK., Department of Biostatistics, Epidemiology and Informatics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA., Department of Biological Sciences, Covenant University, Ota, Nigeria., Department of Genetics, University of São Paulo, São Paulo, Brazil., Department of Urology, Morriston Hospital, Abertawe Bro Morgannwg University Health Board, Swansea, UK., Department of Biochemistry, Covenant University, Ota, Nigeria., Department of Community Medicine, Aminu Kano Teaching Hospital, Bayero University, Kano, Nigeria., Computer and Information Sciences, Covenant University, Ota, Nigeria., Department of Health Studies, Texas Woman's University, Denton, Texas, USA., School of Pharmacy and Biomedical Sciences, University of Central Lancashire, Preston, UK., Dana Farber Cancer Institute and Harvard T.H. Chan School of Public Health, Boston, Massachusetts, USA.