Prevalence of chronic kidney disease in Kinshasa: results of a pilot study from the Democratic Republic of Congo.

BACKGROUND: The burden of chronic kidney disease (CKD) in sub-Saharan Africa is unknown. The aim of this study was to investigate the prevalence and the risk factors associated with CKD in Kinshasa, the capital of the Democratic Republic of Congo (DRC).

METHODS: In a cross-sectional study, 503 adult residents in 10 of the 35 health zones of Kinshasa were studied in a randomly selected sample. Glomerular filtration rate was estimated using the simplified Modification of Diet in Renal Disease Study equation (eGFR) and compared with the Cockcroft-Gault equation for creatinine clearance. The associations between health characteristics, indicators of kidney damage (proteinuria) and kidney function (<60 ml/min/1.73 m(2)) were examined.

RESULTS: The prevalence of all stages of CKD according to K/DOQI guidelines was 12.4% [95% confidence interval (CI), 11.0-15.1%]. By stage, 2% had stage 1 (proteinuria with normal eGFR), 2.4% had stage 2 (proteinuria with an eGFR of 60-89 ml/min/1.73 m(2)), 7.8% had stage 3 (eGFR, 30-59 ml/min/1.73 m(2)) and 0.2% had stage 5 (eGFR < 15 ml/min/1.73 m(2)). Hypertension and age were independently associated with CKD stage 3. The prevalences of major non-communicable diseases considered in this study were 27.6% (95% CI, 25.7-31.3%) for hypertension, 11.7% (95% CI, 10.3-14.4%) for diabetes mellitus and 14.9% (95% CI, 13.3-17.9%) for obesity. Hypertension was also independently associated with proteinuria.

CONCLUSION: More than 10% of the Kinshasa population exhibits signs of CKD, which is affecting adults in their productive years. Risk factors for CKD, including hypertension, diabetes and obesity, are increasing. These alarming data must guide current and future healthcare policies to meet the challenge raised by CKD in this city and hopefully in the whole country.