Race and other risk factors for incident proteinuria in a national cohort of HIV-infected veterans

Background: Proteinuria in human immunodeficiency virus (HIV)-infected individuals has been associated with poorer outcomes. We examined risk factors associated with the development of proteinuria in a national registry of HIV-infected veterans.

Methods: A total of 21,129 HIV-infected veterans of black and white race without preexisting kidney disease were receiving health care in the Veterans' Health Administration (VHA) medical system between 1997 and 2011. Using the VHA electronic record system, we identified kidney-related risk factors (hypertension, diabetes, and cardiovascular disease) and HIV-related risk factors (CD4 lymphocyte count, HIV RNA level, hepatitis C virus, and hepatitis B virus) for developing proteinuria. Proteinuria was defined by 2 consecutive dipstick measures of 1⁺ or higher. The Fine-Gray competing risk model was used to estimate association between clinical variables and incident proteinuria, while accounting for intervening mortality events.

Results: During follow-up (median = 5.3 years), 7031 patients developed proteinuria. Overall, black race compared with white race was associated with a higher risk of proteinuria {hazard ratio [95% confidence interval (CI)] = 1.51 [1.43 to 1.59]}, but the association was stronger at younger ages (P interaction <0.001). Age-stratified risk of proteinuria for blacks relative to whites was greatest among veterans <30 years [2.19 (1.66 to 2.89)] and the risk diminished with increasing age [1.14 (0.97 to 1.34) for >60 years]. We found the race difference to be stronger for the outcome of 2⁺ or higher proteinuria [2.13 (1.89 to 2.39)]. Both HIV-related and traditional risk factors were also associated with incident proteinuria (P < 0.05).

Conclusions: Compared with whites, risk of proteinuria was higher in black veterans with HIV infection, particularly at younger ages. In both races, HIV- and kidney-related risk factors were associated with higher proteinuria risk.