Renal impairment risk in Indigenous and non-Indigenous people who take HIV pre-exposure prophylaxis (PrEP): a retrospective cohort study

Background Tenofovir disoproxil-containing HIV pre-exposure prophylaxis (PrEP) is associated with a small risk of renal impairment. How this risk may differ in Aboriginal and Torres Strait Islander peoples (hereafter, respectfully, 'Indigenous') who have higher rates of chronic kidney disease and associated risk factors than non-Indigenous Australians, has yet to be described. Methods A retrospective longitudinal open cohort study of adults with a baseline estimated glomerular filtration rate (eGFR) >= 60 mL/min/1.73 m(2) commencing tenofovir disoproxil-containing PrEP as part of routine care was conducted. Client data were collected from 67 clinics participating in the Australian Collaboration for Coordinated Enhanced Sentinel Surveillance of Sexually Transmissible Infections and Blood Borne Viruses network between January 2012 and December 2019. The primary outcome was the rate of new renal impairment, defined as an eGFR of <60 mL/min/1.73 m(2) or >25% decline of eGFR from baseline. Results Of the 8696 adults, 203 identified as Indigenous and were eligible for inclusion. The median age was 34 years (IQR 28-44), 96.8% were men who have sex with men and 90.1% resided in major cities. Indigenous clients were less likely to have a baseline eGFR 60-90 mL/min/1.73 m(2) (15.8% vs 24.1%; P = 0.006). Over a median follow-up period of 1.7 years (IQR 1.1-2.4), rates of renal impairment were similar for Indigenous and non-Indigenous clients: 5.6 events/1000 person-years (95% CI 1.4-22.8) and 4.8 events/1000 person-years (95% CI 3.9-6.1) respectively (P = 0.83). Conclusions Renal impairment was rare among Australians commencing PrEP as part of usual care. We observed no difference in the development of renal impairment among Indigenous and non-Indigenous Australians.