Assessing renal function and its association with cardiovascular factors among human immunodeficiency virus-infected patients

Abstract

The purpose of this study was to investigate the effect of cART on renal function and assess the association between renal function and cardiovascular risk factors in a black rural HIV-positive population in Limpopo Province, Mankweng district. We have conducted a cross-sectional study which included both male and female cART-treated patients (n=84), cART-naïve patients (n=27) and HIV-negative controls (n=44). We have measured biomarkers of renal function (plasma cystatin C, clusterin, retinol binding protein 4 [RBP4]) and determined the estimated glomerular filtration rate (eGFR) using the chronic kidney disease-epidemiology collaboration formula (CKD-EPI). We have also measured blood pressure (BP), body mass index (BMI) and fasting blood glucose (FBG). The prevalence of renal dysfunction was similar among the study groups. A significant difference in RBP4 was found among the groups after controlling for covariates (age, gender, alcohol consumption, BMI, systolic blood pressure and FBG) (F (2, 146) = [4.479], p=0.010). The significant difference in RBP4 was specifically observed between the cART-treated and cART-naïve groups (p=0.008). Cystatin C, clusterin and eGFR were not significantly different among the study groups after controlling for the covariates. The cardiovascular risk factors age (β=0.207; p=0.039), CD4+ T-cell count (β=-0.236; p=0.040), and duration of cART (β=0.232; p=0.043) were independently associated with cystatin C. The use of cART independently associated with RBP4 (β=0.282; p=0.004). Age (β=-0.363; p=0.001), CD4+ T-cell count (β=0.222; p=0.034) and duration of cART (β=-0.230; p=0.034) independently associated eGFR. Renal dysfunction is common in this HIV-positive population, with similar rates as the HIV-negative population. Plasma cystatin C as a promising alternative renal biomarker need to be re-evaluated in this HIV-positive population. RBP4 may be a more promising renal function biomarker in the HIV-positive population. Cardiovascular risk factors are associated with renal dysfunction in this rural HIV-positive population and CD4+ T-cell count may be an independent predictor for renal function.