Understanding the Association Between Substance Use and Loneliness in Midlife and Older Adults.

Substance use, a significant public health concern, may be associated with worsening social connections and feelings of loneliness among adult populations. This study examined the associations between substance use (i.e., binge alcohol, e-cigarette, and traditional cigarette use) and loneliness among adults aged ≥50 years residing in the US. We conducted a secondary analysis of cross-sectional data from the 2023 Behavioral Risk Factor Surveillance System Social Determinant of Health Equity module. The sample included 138,614 adults aged ≥50 years, representing approximately 55.4 million individuals in this age group. Substance use was the key independent variable and categorized into two groups: no substance use and substance use-participants who reported current use of ≥1 of three substances (i.e., binge alcohol, e-cigarette, and traditional cigarette use). Overall, 19.0% of participants reported using ≥1 substance use, 21.0% reported feeling lonely sometimes, and 5.1% feeling lonely always/usually. Participants who reported using ≥1 substance had a 17.0% higher relative risk of feeling lonely always/usually (compared to feeling never/rarely lonely) than adults who did not report substance use, after adjusting for all covariates (RRR 1.17; 95% CI 1.10-1.35;