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) <60ml/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 ≥60ml/min (group-II). The study was retrospective, included patients 16yrs 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 2861 and 7526 patients, respectively. In group-I, improvement in CrCl was observed in 40.1% (n=1,146), and was associated with stage IV of CrCl (adjusted Odds Ratio [aOR]=13.4 [95%CI: 6.7 – 26.9, p<0.001]); male gender (aHR=1.8 [95%CI: 1.5 – 2.2, p<0.001]); and a poor HIV-status (aHR=1.2 [95%CI: 1.0 – 1.4], p=0.033). In groups-I and group-II, respectively, decline occurred in 2.3% and 13.0%, (p<0.001); transition to lower stages occurred in 1.0% and 25.2% (p<0.001); and migration to stage IV CrCl occurred in 1.0% and 0.5% (p<0.001). 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 <60ml/min