Background:  Chronic kidney disease remains a prevalent problem among HIV-infected patients. The contribution of HAART and HIV disease factors relative to traditional factors toward kidney dysfunction remains controversial.

Methods:  Cross-sectional study of all HIV-infected patients seen at the Washington University HIV Outpatient Clinic during the year 2005. Demographics, medication history, co-morbidities, and laboratory data were collected from an electronic database and manual chart review. Multivariate logistic regression was used to identify independent predictors of declining glomerular filtration rate (GFR) from among factors significant in univariate analysis. GFR in mL/minute/1.73 m² was determined using the simplified modification of diet in renal disease equation. Chronic kidney disease was defined as a GFR <60. Results were compared with those of persons from the National Health and Nutrition Examination Study III (NHANES), matched for age, race, and gender.

Results:  Data were available for 847 matched pairs. Among the HIV-infected, 63% were men, 34% Caucasian, mean age 39.6 years, mean log₁₀ viral load 3.04 copies, median CD4 count 397 cells/mm³ (IQR 214 to 590); 29% had proteinuria, 4% had chronic kidney disease, and 42% had GFR <90. Patients on HAART (63%) had lower mean GFR than patients not on HAART (92.0 vs 101.6, p <0.01). In multivariate analyses, excluding variables in the modification of diet in renal disease equation (age, race, gender), significant predictors of GFR decline were diagnoses of hypertension, hyperlipidemia, any proteinuria, any use of tenofovir, and lower viral load (all p <0.01). Compared to NHANES, HIV-infected patients had lower mean GFR (95.5 vs 103.6, p <0.01) and higher prevalence of chronic kidney disease (4% vs 2%, p <0.01). HIV-infected patients weighed significantly less, were more likely to use tobacco or illicit drugs, and had higher prevalence of hepatitis B and hepatitis C infection than NHANES subjects (all p <0.01). The prevalence of diabetes and hypertension were similar between groups.

Conclusions:  In this cohort, the prevalence of chronic kidney disease is low, but remains higher than that of the general population. Nevertheless, early declines in GFR are prevalent and appear to be attributable not only to traditional risk factors but also to HAART. Chronic kidney disease is likely to become more prominent as patients age and are on long-term therapy.