OBJECTIVE: Tenofovir disoproxil fumarate (TDF), an integral component of first-line antiretroviral therapy (ART), is associated with nephrotoxicity, including a decline in glomerular filtration rate (GFR). The study describes renal function outcomes and risk factors for TDF-associated renal impairment in a Ghanaian cohort who had no known risk factors for renal impairment.

PATIENTS AND METHODS: We included 97 HIV patients who were antiretroviral-naïve at baseline, initiated a TDF-based ART between 2010 and 2018, and had documented baseline renal function tests. We measured follow-up creatinine and urea levels and calculated eGFR using the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) formula. We described changes in eGFR from ART initiation using paired t-test.

RESULTS: In patients with eGFR >90 ml/min and <90 ml/min at baseline, the mean eGFR change was -5 ml/min (95% CI: -13-2.7, p = 0.1981) and 31 ml/min (95% CI: 23-39, p < 0.0001) respectively. All 5 patients in whom TDF was initiated in error (baseline eGFR <50 ml/min), had eGFR above 60 ml/min during follow-up. Overall, 5 (3.9%) patients experienced moderate renal impairment (eGFR; 30-59 ml/min) and no incidence of severe renal impairment (eGFR; <30 ml/min). Patients who had been on treatment for <24 months had a mean eGFR change of 21 ml/min (95% CI: 12-31, p < 0.0001) but no significant change was observed in those who had been on treatment for >24 months. Significant associations with decreased eGFR included longer duration of treatment and older age.

CONCLUSIONS: TDF-associated renal impairment was uncommon; however, the risk increases with age and long-term treatment. In this setting, regular monitoring of renal function should be targeted at higher-risk patients.