Incidence and Risk Factors of Renal Dysfunction in Patients on Nevirapine-Based Regimens at a Referral Hospital in Kenya

Abstract

Introduction: Nevirapine-based regimens are the most commonly used ART in Kenya. There is little literature on the renal toxicity of NNRTIS in Kenyan settings. Some studies in Asia have demonstrated an association of NNRTIs and renal toxicity. Given that NNRTIs may cause renal toxicity, clinical studies on their contribution to the same are required.

Objectives: To evaluate the incidence and risk factors for renal dysfunction in HIV adult patients on Nevirapine based regimens.

Methodology: The design was a descriptive (right censored arm) hospital based retrospective cohort study carried out at a national referral hospital. Ethical approval was obtained. The study population was patients on Nevirapine based regimens seen between May and August, 2014. Convenient sampling was used to recruit 241 patients. Estimated glomerular filtration rate (eGFR) was calculated using the Modification of Diet in Renal Disease (MDRD) formula. Patients with eGFR < 50ml/min/1.73m² were considered to have renal dysfunction. Data obtained by the patient interviews and abstraction of patient files and was analyzed using STATA software. Ordered Logistic regression was used to identify covariates that determine the severity of renal dysfunction.

Results: The incidence of renal dysfunction was 4.3% (95% C.I, 1.68-6.94).Five (2.1%)   patients had a low eGFR at baseline, while ten (8.3%) patients had elevated serum creatinine (above 120µg/l). None of the patients developed severe renal dysfunction. Seventy (32%) and ten (4.6%) had mild and moderate renal dysfunction respectively. The females had a higher risk of developing renal dysfunction (adjusted O.R 0.48 (95% C.I 0.24-1.04; p=0.04). Alcohol consumption was a significant predictor of renal dysfunction (adjusted O.R 1.84 (95% C.I 1.01-3.29; p=0.04).All fifteen patients with a BMI of over 18.5 had elevated eGFR of below 50ml/min/1.73m.²Patients who had been initiated on stavudine based regimens had the highest incidence of renal dysfunction.

Conclusion: Routine eGFR calculations should be done at each clinical visit. Early detection of risk factors and systematic screening should be advocated for improved patient care.

Key Words: Body Mass Index, Renal dysfunction, Stavudine, Nevirapine