Effect of tenofovir containing ART on renal function in patients with moderate/severe reduced creatinine clearance at baseline: a retrospective study at two referral hospitals in Namibia

Prescription of tenofovir disoproxil fumarate (TDF) for patients with baseline creatinine clearances (CrCl) <60 mL/min is said to increase risk of further decline in CrCl. Study objectives were to assess incidence of improvement and predictors thereof; to assess incidence of decline and transition to lower stages of CrCl; and comparison of declines between patients with a baseline CrCl < 60mL/min (group-I) and ≥ 60 mL/min (group-II). The study was retrospective, included patients 16 yrs or older who received TDF-containing ART. Improvement and decline were defined as ≥ 25% increase or decrease in CrCl, respectively. Binary logistic regression was performed to identify predictors of improvement. Groups I and II had 2862 and 7526 patients, respectively. In group-I, improvement in CrCl was observed in 40.1% (n = 1146), and was associated with stage IV of CrCl (adjusted Odds Ratio [aOR]=13.4 [95% CI: 6.7 - 26.9, P <.001]); male gender (aHR = 1.8 [95% CI: 1.5 - 2.2, P <.001]); and a poor HIV-status (aHR = 1.2 [95% CI: 1.0 - 1.4], P =.033). In group-I and group-II, respectively, decline occurred in 2.3% and 13.0%, (P <.001); transition to lower stages occurred in 1.0% and 25.2% (P <.001); and migration to stage IV CrCl occurred in 1.0% and 0.5% (P <.001). Improvement was more likely than decline in group-I patients. Although, group-I patients were more likely to experience new onset severe reduced CrCl than group-II patients, the proportions were extremely low. TDF should not be withheld from HIV-positive patients with a baseline CrCl < 60 mL/min.