The objective of this study was to develop a scoring system to predict 5-year risk of developing chronic kidney disease in HIV-infected individuals and to estimate difference in risk associated with tenofovir disoproxil fumarate use. 21,590 HIV-infected men from the Veterans Health Administration initiating antiretroviral therapy from 1997 to 2010 were selected for this analysis. During a median follow-up of 6.3 years, 2,059 chronic kidney disease events occurred. Chronic kidney disease was defined as the first occurrence of an estimated glomerular filtration rate below < 60 ml/min per 1.73m 2 . A point-based score was developed using multi-variable Cox regression models. Dominant contributors to the chronic kidney disease risk score were traditional kidney risk factors (age, glucose, systolic blood pressure, hypertension, triglycerides, proteinuria), as well as CD4 + cell count, while HIV RNA was not. The overall 5-year event rate was 7.7% in tenofovir users and 3.8% in nonusers (overall adjusted hazard ratio 2.0, 95% confidence interval 1.8–2.2). There was a progressive increase in 5-year chronic kidney disease risk, ranging from less than 1% to 16% in nonusers of tenofovir, and from 1.4 to 21.4% among tenofovir users. The duration of tenofovir exposure and the increased risk score were associated with higher risk of chronic kidney disease.

In conclusion, the chronic kidney disease risk score can be used to predict an HIV-infected individual's absolute risk of developing chronic kidney disease over 5 years and may facilitate clinical decision-making around tenofovir use. The limitations of this study are its observational nature, the absence of consideration of active HCV infection in the analysis. This risk score algorithm needs to be validated in an independent cohort and doesn't substitute for regular clinical and laboratory monitoring of patients on tenofovir.