Risk and Cost Associated With Drug–Drug Interactions Among Aging HIV Patients Receiving Combined Antiretroviral Therapy in France

BACKGROUND: We aimed to describe the frequency, risk factors, and costs attributable to drug–drug interactions (DDIs) among an aging French HIV population. METHODS: We conducted a retrospective cohort study using French nationwide health care e-records: the SNIIRAM database. People living with HIV (PLWH) aged >65 years and receiving combined antiretroviral treatment (cART) during 2016 were included. A DDI was defined as “These drugs should not be co-administered,” represented by a red symbol on the University of Liverpool website. Attributable DDIs’ cost was defined as the difference between individuals with and without DDIs regarding all reimbursed health care acts. RESULTS: Overall, 9076 PLWH met the study criteria. Their baseline characteristics were: mean age, 71.3 ± 4.9 years; 25% female; median HIV duration (interquartile range [IQR]), 16.2 (9.5–20.3) years; median comorbidities (IQR), 2 (1–3). During 2016, they received a median (IQR) of 14 (9–21) comedications (non-cART), and 1529 individuals had at least 1 DDI (16.8%; 95% confidence interval [CI], 16.1–17.6). In multivariate analysis, raltegravir or dolutegravir plus 2 nucleoside reverse-transcriptase inhibitors (NRTIs) significantly and independently reduced the risk of DDIs (adjusted odds ratio [aOR], 0.02; 95% CI, 0.005–0.050; P < .0001) compared with non-nucleoside reverse-transcriptase inhibitor plus 2 NRTIs, whereas cART with boosted agents (protease inhibitors or elvitegravir) significantly increased the risk (aOR, 4.12; 95% CI, 3.34–5.10; P < .0001). Compared with propensity score–matched PLWH without DDIs, the presence of DDIs was associated with a $2693 additional cost per year (P < .0001). CONCLUSIONS: The presence of DDIs is frequent and significantly increases health care costs in the aging population of PLWH.