Systematic Reviews
Copyright ©The Author(s) 2015. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Diabetes. Jun 10, 2015; 6(5): 759-773
Published online Jun 10, 2015. doi: 10.4239/wjd.v6.i5.759
Diabetic nephropathy in Africa: A systematic review
Jean Jacques N Noubiap, Jashira Naidoo, Andre P Kengne
Jean Jacques N Noubiap, Internal Medicine Unit, Edéa Regional Hospital, PO BOX 100 Edéa, Cameroon
Jashira Naidoo, Department of Medicine, Groote Schuur Hospital, University of Cape Town, 7925 Observatory, Cape Town, South Africa
Jashira Naidoo, Andre P Kengne, Non-Communicable Diseases Research Unit, South African Medical Research Council, 7505 Cape Town, South Africa
Author contributions: All authors contributed to this work.
Conflict-of-interest: None for all co-authors.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Andre P Kengne, Professor, Medical Research Council of South Africa, PO Box 19070 Tygerberg, 7505 Cape Town, South Africa. andre.kengne@mrc.ac.za
Telephone: +27-21-9380529 Fax: +27-21-9380460
Received: December 8, 2014
Peer-review started: December 9, 2014
First decision: January 20, 2015
Revised: February 18, 2015
Accepted: March 16, 2015
Article in press: March 18, 2015
Published online: June 10, 2015
Abstract

AIM: To determine the prevalence and incidence of diabetic nephropathy in Africa.

METHODS: We performed a systematic narrative review of published literature following the MOOSE Guidelines for Meta-Analysis and Systematic Reviews of Observational Studies. We searched PubMed-MEDLINE for all articles published in English and French languages between January 1994 and July 2014 using a predefined strategy based on the combination of relevant terms and the names of each of the 54 African countries and African sub-regions to capture the largest number of studies, and hand-searched the reference lists of retrieved articles. Included studies reported on the prevalence, incidence or determinants of chronic kidney disease (CKD) in people with diabetes within African countries.

RESULTS: Overall, we included 32 studies from 16 countries; two being population-based studies and the remaining being clinic-based surveys. Most of the studies (90.6%) were conducted in urban settings. Methods for assessing and classifying CKD varied widely. Measurement of urine protein was the most common method of assessing kidney damage (62.5% of studies). The overall prevalence of CKD varied from 11% to 83.7%. Incident event rates were 94.9% for proteinuria at 10 years of follow-up, 34.7% for end-stage renal disease at 5 years of follow-up and 18.4% for mortality from nephropathy at 20 years of follow-up. Duration of diabetes, blood pressure, advancing age, obesity and glucose control were the common determinants of kidney disease.

CONCLUSION: The burden of CKD is important among people with diabetes in Africa. High quality data from large population-based studies with validated measures of kidney function are still needed to better capture the magnitude and characteristics of diabetic nephropathy in Africa.

Keywords: Diabetes, Diabetes nephropathy, Chronic kidney disease, Epidemiology, Prevalence, Incidence, Mortality, Africa, Systematic review

Core tip: Chronic kidney disease is a serious health threat for people with diabetes in Africa, with prevalence figures ranging from 11% to 83.7%. The incidence estimates suggest that 95% of people with diabetes may have proteinuria after 10 years from diabetes diagnosis; about 35% may develop end-stage renal disease after 5 years and 18% die from nephropathy after 20 years of disease duration. Hypertension, obesity, poor glycemic control and diabetes duration are the main risk factors of chronic kidney disease among diabetic patients in Africa. High quality data are needed to refine the epidemiology of diabetic nephropathy on the continent.