Veteran adherence to oral versus injectable AUD medication treatment

Area of Science:

• Pharmacology
• Addiction Medicine
• Health Services Research

Background:

• Medication adherence significantly impacts treatment efficacy for alcohol use disorder (AUD).
• Conflicting evidence exists regarding adherence rates between oral and injectable AUD pharmacotherapies.
• Limited data are available on adherence risk factors in the veteran population.

Purpose of the Study:

• To compare adherence rates between oral and injectable AUD treatments in veterans during the first year of therapy.
• To identify patient characteristics associated with high versus low medication adherence.
• To compare alcohol-related readmission and discontinuation rates between treatment groups.

Main Methods:

• Retrospective chart review of veterans undergoing AUD pharmacotherapy.
• Utilized the portion of days covered model to assess adherence at 3, 6, 9, and 12 months.
• Compared adherence rates, patient characteristics, readmission rates, and discontinuation rates.

Main Results:

• Injectable extended-release (XR) naltrexone demonstrated higher adherence than oral naltrexone and disulfiram at multiple time points.
• Acamprosate showed similar adherence to XR naltrexone, and higher adherence than oral naltrexone at 9 and 12 months.
• Higher adherence was associated with more frequent mental health clinic visits and previous medication trials; discontinuation and readmission rates did not differ significantly.

Conclusions:

• XR naltrexone may offer improved adherence over oral naltrexone and disulfiram, but not acamprosate.
• Increased patient engagement with mental health services and prior medication experience may enhance AUD treatment adherence.