Predictors of nephropathy in sickle cell disease: A cross-sectional analysis across age and clinical phenotypes in Zaria, Nigeria.

BACKGROUND: Sickle cell disease (SCD) is associated with significant complications, including nephropathy, which can progress to end-stage renal disease. While risks for SCD nephropathy have been identified globally, their specific prevalence and predictors in Nigerian, especially across age and clinical phenotypes, are less well understood. This study assessed the prevalence and predictors of nephropathy among Nigerian SCD patients. METHODS: This was a cross-sectional study among paediatrics, adolescent, and adult patients with SCD attending hematology clinics of Ahmadu Bello University Teaching Hospital (ABUTH), Zaria. Interviewer-administered questionnaires were utilised to collect demographic and clinical data. Nephropathy was defined by the presence of proteinuria, haematuria, or eGFR <60 ml/min. Patients were classified into hyper-haemolytic and vaso-occlusive sub-phenotypes. Statistical analyses involved Mann-Whitney U tests, chi-square tests, and logistic regression, with a significance level set at p < 0.05. RESULTS: A total of 311 SCD patients were enrolled, with a median age of 17 (IQR 9-25) years and 65% female. Nephropathy was present in 13.8% of patients, with significantly higher prevalence among adults (23.7%) compared to adolescents (9.1%) and paediatrics patients (3.8%) respectively (X2= 19.27, p < 0.001). The odds of nephropathy were significantly higher in adults (OR 5.57, 95% CI: -0.53-3.96) and females (OR 2.05, 95% CI: 1.72-3.16). Patients with hyper-haemolytic complications had higher odds of nephropathy than those with a vaso-occlusive phenotype (P = 0.366). CONCLUSION: The prevalence of nephropathy in Nigerian SCD patients increases with age and is more common in females, with hyper-hemolytic sub-phenotypes showing a higher risk profile.