Impaired renal function in a rural Ugandan population cohort

Abstract

Background: Chronic kidney disease (CKD) is an important cause of morbidity and mortality globally. However, there are limited data on the prevalence of impaired kidney function in sub-Saharan Africa. We aimed to determine the prevalence of CKD and associated factors in a rural Ugandan population. Methods: We undertook a study of a representative sample of the General Population Cohort in South-western Uganda. We systematically collected data on cardiovascular disease risk factors, anthropometric measurements and blood tests for haemoglobin, HIV, HbA1c, Hepatitis B and C and serum creatinine.  The estimated glomerular filtration rate (eGFR) was calculated using the CKD-Epi formula, without the race component of the equation. Results: A total of 5,979/6,397 (93.5%) participants had valid creatinine results. The mean age was 39 years (Range: 16-103 years) and 3,627 (60.7%) were female. HIV prevalence was 9.7% and about 40% of the population were pre-hypertensive or hypertensive. The mean serum creatinine level was 0.75 mg/dl (95% CI 0.74–0.75), and the average eGFR was 109.3 ml/min/1.73 m 2 (95% CI 108.8–109.9). The overall prevalence of CKD (eGFR <60 ml/min/1.73 m 2 ) was 1.64% (98/5,979) (95% CI 1.34–1.99).  Additionally, 4,792 (80.2%) were classified as normal (eGFR ≥90 ml/min/1.73 m 2 ), 1,089 (18.2%) as low (eGFR 60–89 ml/min/1.73 m 2 ), 91 (1.52%) as moderate (eGFR 30–59 ml/min/1.73 m 2 ), 4 (0.07%) as severe (eGFR 15-29 ml/min/1.73 m 2 ), and 3 (0.05%) classified as having kidney failure (eGFR <15 ml/min/1.73 m 2 ).  When age-standardised to the WHO Standard Population the prevalence of CKD was 1.79%. Age above 35 years (OR 78.3, 95% CI 32.3–189), and the presence of hypertension (OR 2.98, 95% CI 1.47-6.02) and anaemia (OR 2.47, 95% CI 1.37-4.42) were associated with CKD. Conclusion: We found a substantial prevalence of CKD in rural Uganda, strongly associated with high blood pressure and anaemia.