Demographic and clinical profile of black patients with chronic kidney disease attending Charlotte Maxeke Johannesburg Academic Hospital (CMJAH) in Johannesburg, South Africa

Abstract

AbstractBackgroundThe prevalence of chronic kidney disease (CKD) is increasing worldwide; black patients have an increased risk of developing CKD and end stage kidney disease (ESKD) at significantly higher rates than other races.MethodsA cross sectional study was carried out on black patients with CKD attending the kidney outpatient clinic at Charlotte Maxeke Johannesburg Academic Hospital (CMJAH) in South Africa, between September 2019 to March 2020. Demographic and clinical data were extracted from the ongoing kidney outpatient clinic records and interviews, and were filled in a questionnaire. Patients provided blood and urine for laboratory investigations as standard of care, data were descriptively and inferentially analysed using STATA version 17. Multivariable logistic regression analysis was used to identify demographic and clinical data associated with advanced CKD.ResultsA total of 312 black patients with CKD were enrolled during the study period; 58% patients had advanced CKD, of whom 31.5 % had grossly increased proteinuria, 96.7 % had hypertension, 38.7 % had diabetes mellitus and 38.1 % had both hypertension and diabetes mellitus. For patients with advanced CKD, the median age was 61 (IQR 51-69) years, eGFR 33 (30 -39) mL/min/1.73 m2, serum bicarbonate 22 (IQR 20 – 24), hemoglobin 12.9 (IQR 11.5 – 14.0) g/dl, serum transferrin 2.44 (IQR 2.23 – 2.73) g/L, serum uric acid 0.43 (IQR 0.37 – 0.53) and serum potassium 4.4 (IQR 3.9 – 4.8) mmol/L. The prevalence of metabolic acidosis was 62.4 %, anemia 46.4 %, gout 30.9 %, low transferrin levels 16.6 % and hyperkalemia 8.8 % among those with advanced CKD, while the prevalence of metabolic acidosis and anemia was 46.6 % and 25.9 % respectively in those with early CKD. Variables with higher odds for advanced CKD after multivariable logistic regression analysis were hypertension (OR 3.3, 95 % CI 1.2 - 9.2, P = 0.020), diabetes mellitus (OR 1.8, 95 % CI 1.1 - 3.3, P = 0.024), severe proteinuria (OR 3.5, 95 % CI 1.9 - 6.5, P = 0.001), angina (OR 2.5, 95 % CI 1.2 - 5.1, P = 0.008), anaemia (OR 2.9, 95% CI 1.7 - 4.9, P= 0.001), hyperuricemia (OR 2.4, 95 % CI 1.4 - 4.1, P = 0.001), and metabolic acidosis (OR 2.0, 95% CI 1.2 - 3.1, P= 0.005). Other associations with advanced CKD were widow/widower (OR 3.2, 95 % CI 1.4 - 7.4, P = 0.006), low transferrin (OR 2.4, 95% CI 1.1 - 5.1, P= 0.028), hyperkalemia (OR 5.4, 95% CI 1.2 - 24.1, P= 0.029), allopurinol (OR 2.4, 95 % CI 1.4 - 4.3, P = 0.005) and doxazosin (OR 1.9, 95% CI 1.2 - 3.1, P = 0.006).ConclusionHypertension and diabetes mellitus were strongly associated with advanced CKD, suggesting a need for primary and secondary population-based prevention measures. Metabolic acidosis, anaemia with low transferrin levels, hyperuricemia and hyperkalemia were highly prevalent in our patients, including those with early CKD, and they were strongly associated with advanced CKD, calling for the proactive role of clinicians and dietitians in supporting the needs of CKD patients in meeting their daily dietary requirements towards preventing and slowing the progression of CKD.