Using PEth and AUDIT-4 to Detect Harmful Alcohol Use Among People with Severe Substance Use

Subst Use Misuse. 2026 May 12:1-10. doi: 10.1080/10826084.2026.2634253. Online ahead of print.

Abstract

Aims: People with severe substance use (PWSSU) face increased health risks, which contributes to higher mortality rates and reduced life expectancy. Concurrent harmful alcohol use may further exacerbate these risks but is often overlooked in this population. The aim of this study was to assess levels of harmful alcohol use among PWSSU.

Methods: Participants were recruited from two sites in Oslo, Norway, that either shelters and/or treats PWSSU. Alcohol and substance use was assessed with self-report questionnaires and a blood sample. The blood sample was analyzed for 20 commonly used illicit and medicinal substances, ethanol and phosphatidylethanol (PEth). Harmful alcohol use was defined as AUDIT-4 ≥ 7 (men)/≥5 (women), having PEth concentration ≥ 300 nM, or both. Associations between harmful alcohol use and sex, age, and substance use profile were assessed.

Results: Of the 165 participants (70% male) included in the study, most (n = 94, 57%) stated opioids as their main substance, and polysubstance use was common (median substances in blood samples = 5). Alcohol use in the last 12 months was reported by 75% (n = 125) of the participants. Harmful alcohol use was detected in 28 (24%) of male participants and 23 (47%) of female participants. Being female, decreasing age, and reporting a non-opioid as main substance were associated with harmful alcohol use.

Conclusion: A harmful drinking pattern was frequently observed among PWSSU, especially among women. In addition to treating excessive substance use in this underserved group, reduction of harmful alcohol use would be beneficial to reduce health risk.

Keywords: Alcohol use; co-use; harm reduction; substance use.