Polypharmacy and risk of non-fatal overdose for patients with HIV infection and substance dependence.

INTRODUCTION

People living with HIV (PLWH) are at risk of both polypharmacy and unintentional overdose yet there are few data on whether polypharmacy increases risk of overdose. The study objective was to determine if the number and type of medication (e.g., sedating) were associated with non-fatal overdose (OD) among PLWH with past-year substance dependence or a lifetime history of injection drug use.

MATERIALS AND METHODS

This was a longitudinal study of adults recruited from two urban, safety-net HIV clinics. Outcomes were i) lifetime and ii) past-year non-fatal OD assessed at baseline and a 12-month follow-up. We used logistic regression to examine the association between each outcome and the number of medications (identified from the electronic medical record) in the following categories: i) overall medications, ii) non-antiretroviral (non-ARV), iii) sedating, iv) non-sedating, as well as any vs no opioid medication and any vs no non-opioid sedating medication. Covariates included demographics, medical comorbidities, depressive and anxiety symptoms, and substance use.

RESULTS

Among 250 participants, 80% were prescribed a sedating medication, 50% were prescribed an opioid; 51% exceeded risky drinking limits. In the past month, 23% reported illicit opioid use and 9% illicit opioid sedative use; 37% reported lifetime non-fatal OD and 7% past-year non-fatal OD. The median number (interquartile range) of total medications was 10 (7, 14) and 2 (1, 3) sedating. The odds of lifetime non-fatal OD were significantly higher with each additional sedating medication (OR 1.26, 95% CI 1.08, 1.46) and any opioid medication (OR 2.31; 95% CI 1.37, 3.90), but not with each overall, non-ARV, or non-sedating medication. The odds of past year non-fatal OD were greater with each additional sedating medication (OR 1.18; 95% CI 1.00, 1.39, p=0.049), each additional non-ARV medication (OR 1.07; 95% CI 1.00, 1.15, p=0.048), and non-significantly for any opioid medication (OR 2.23; 95% CI 0.93, 5.35).

CONCLUSIONS

In this sample of PLWH with substance dependence and/or injection drug use, number of sedating medications and any opioid were associated with non-fatal overdose; sedating medications were prescribed to the majority of patients. Polypharmacy among PLWH and substance dependence warrants further research to determine whether reducing sedating medications, including opioids, lowers overdose risk.