Increasing Risk for Infective Endocarditis Among People Who Inject Drugs

The risk for infective endocarditis among people who inject drugs is on the rise and appears to be associated with an increase in prescriptions for hydromorphone, according to retrospective study results published in the Canadian Medical Association Journal.

Because of an increase in the illicit use of prescription opioids, there has also been an increase in cases of infective endocarditis related to injection drug use.

Hydromorphone is associated with a higher risk for contamination and bacteremia from injection compared with oxycodone; therefore, an increase in hydromorphone use may explain this increase in infective endocarditis.

Researchers conducted a population-based time series analysis using health administrative databases in Ontario, Canada, and measuring the quarterly risk for admissions for infective endocarditis related to injection drug use and changes in opioid prescription rates from 2006 to 2015.

Traditional controlled-release oxycodone was removed from the Canadian market in 2011; therefore, this served as the intervention point for the study. The researchers found that before the intervention point, there was a mean of 13.4 admissions for infective endocarditis per quarter; after the intervention, there was a mean of 35.1 admissions per quarter.

In addition, at the beginning of the observation period, 16% of all opioid prescriptions were for hydromorphone, whereas by the end of the observation period, hydromorphone accounted for 53% of all opioid prescriptions. The risk for infective endocarditis appeared to increase earlier than the intervention point and in parallel with the rise in hydromorphone prescriptions.

“The risk of infective endocarditis related to injection drug use is increasing and is temporally associated with increasing prescriptions for hydromorphone. This relation warrants further exploration,” concluded the authors.

Reference

Weir MA, Slater J, Jandoc R, Koivu S, Garg AX, Silverman M. The risk of infective endocarditis among people who inject drugs: a retrospective, population-based time series analysis. CMAJ. 2019;191(4):E93-E99.