Incidence of stage 3 chronic kidney disease and progression on tenofovir-based regimens

Objective: To describe the incidence of rapid kidney function decline (RKFD), and stage 3 chronic kidney disease (CKD) in HIV-1-infected adults initiated on tenofovir-containing antiretroviral therapy. Methods: A retrospective cohort study at the infectious diseases clinic of Tygerberg Academic Hospital in Cape Town, South Africa. Patients with more than 3ml/min per year decline in estimated glomerular filtration were classified as having RKFD, and stage 3 CKD was defined as a value less than 60ml/min per 1.73m 2. We used logistic and Cox proportional hazards regression models to determine factors associated with RKFD and stage 3 CKD. Results: Of 650 patients, 361 (55%) experienced RKFD and 15 (2%) developed stage 3 CKD during a median interquartile range follow-up time of 54 (46.6-98) weeks. For every 10-year increase in age and 10ml/min lower baseline estimated glomerular filtration, the odds of RKFD increased by 70% [adjusted odds ratio=1.70, 95% confidence interval (CI) 1.36-2.13] and 57% (adjusted odds ratio=1.57, 95% CI 1.38-1.80), respectively. Each 10-year older age was associated with a 1.90-fold increased risk of developing stage 3 CKD (adjusted hazard ratio=1.90, 95% CI: 1.10-3.29). Women had about four-fold greater risk of stage 3 CKD compared with men (adjusted hazard ratio=3.96, 95% CI: 1.06-14.74). Conclusion: About half of our study population developed RKFD but only 2% progressed to stage 3 CKD. Approaches that provide balanced allocation of limited resources toward screening and monitoring for kidney dysfunction and HIV disease management are critically needed in this setting.