Urinary Transforming Growth Factor-Beta 1 (uTGF-β1) and Prevalent CKD Risk in HIV-Positive Patients in West Africa

Introduction: This study investigated the association of urinary transforming growth factor-beta 1 (uTGF-beta 1) with prevalent chronic kidney disease (CKD) in the HIV-infected population. Methods: HIV-positive patients without CKD (HIV+CKD-, n = 194) and 114 with CKD (HIV+CKD+) who did not have hypertension, diabetes mellitus, or hepatitis B or C, had their urinary protein-creatinine ratio (uPCR), serum transforming growth factor (TGF)-beta 1, and uTGF-beta 1 measured. uTGF-beta 1-creatinine ratios (uTGF-beta 1Cr) were calculated. Spearman correlation was used to determine the association between uTGF-beta 1Cr and various attributes, and the Cuzick trend test was used to assess the presence of a linear trend in median uTGF-beta 1Cr levels across the stages of CKD. Multivariable robust linear regression models were used to assess independent association with variability in uTGF-beta 1Cr and estimated glomerular filtration rate (eGFR) levels. Results: The age of the participants was 38.3 +/- 10.3 years with 73.4% women. The median uTGF-beta 1Cr was higher among HIV+CKD+ (4.85 ng/mmol [25th-75th percentile 1.96-12.35] vs. 2.95 [1.02-5.84]; P = 0.001]). There was significant correlation between uTGF-beta 1Cr and age (P = 0.02), eGFR (P = 0.001), and uPCR (P < 0.001) in the HIV+CKD+ group. Among the HIV+CKD+ patients, there was gradual reduction in the median level of uTGF-beta 1Cr with CKD severity (P = 0.04). HIV+CKD+ patients had significantly higher levels of uTGF-beta 1Cr after controlling for potential confounders. Using eGFR as dependent variable, proteinuria explained the changes associated with uTGF-beta 1Cr levels. Conclusion: HIV+CKD+ patients express higher levels of uTGF-beta 1 especially in the early stages of CKD apparently related to proteinuria levels.