Ethnic prevalence of anemia and predictors of anemia among chronic kidney disease patients at a tertiary hospital in Johannesburg, South Africa

Introduction: Anemia is a complication of chronic kidney disease (CKD) that can greatly impact on its prognosis. However, the risk factors for anemia, including the influence of ethnicity, are not well established among the CKD population in Johannesburg.

Methods: This was a cross-sectional study of 353 adult CKD patients attending the renal outpatient clinic of the Charlotte Maxeke Johannesburg Academic Hospital (Johannesburg, South Africa) from June 1, 2016 to December 30, 2016. Sociodemographic and clinical characteristics were obtained using a proforma. Blood samples were collected for serum electrolytes and hematological parameters. Predictors of low hemoglobin and iron deficiency anemia (IDA) were evaluated using multivariable binary logistic regression.

Results: The mean age and prevalence of anemia among the CKD participants were 55.3±15.0 years and 43.18% (95% CI: 38.1%-48.4%), respectively. Blacks had the highest prevalence of anemia (46.9%), while Indians/Asians had the lowest (18.2%). Although the odds of anemia was 3.8-fold higher (odds ratio =3.8, P-value =0.059) among CKD stage V participants as compared to CKD stage I, the relationship between anemia and stages of CKD was non-linear. Diabetes mellitus (odds ratio =2.31, P-value =0.005) had a strong association with anemia among the CKD participants.

Conclusion: Almost half of the CKD participants were anemic, and the odds of anemia did not increase linearly with increasing severity of CKD. There was a marked ethnic disparity in anemia prevalence. Our study highlights the need for risk-based management of anemia among CKD patients.