The Longitudinal Relationship of Loneliness With Frequency and Problematic Use of Alcohol and Cannabis Among Young Adults.

PURPOSE: Despite theoretical frameworks linking loneliness with substance use and misuse, there is little longitudinal research on this relationship. This study examined lagged associations of loneliness with subsequent frequency and problematic use of alcohol and cannabis among young adults.

METHODS

Data were from 4,407 young adults participating in the Community Youth Development Study. A four-item loneliness measure was assessed at ages 21 and 23 years, and alcohol and cannabis use outcomes were assessed at ages 23 and 26 years. Past-month alcohol and cannabis use frequency were treated as ordinal categorical outcomes, and past-year hazardous alcohol use and cannabis use disorder diagnosis were treated as dichotomous outcomes. Marginal structural modeling was used to account for multiple time-fixed and time-varying confounders, including depressive symptoms, substance use, and other psychosocial factors.

RESULTS

Combined across lagged intervals, there was a statistically significant association of standardized loneliness score with greater cannabis use frequency (odds ratio = 1.13; 95% confidence interval [CI]: 1.06, 1.20) but not alcohol use frequency (odds ratio = 1.01; 95% CI: 0.96, 1.06) at the following study wave. Loneliness was also associated with increased likelihood of hazardous alcohol use (prevalence ratio = 1.10; 95% CI: 1.03, 1.17) and cannabis use disorder (prevalence ratio = 1.20; 95% CI: 1.12, 1.29).

DISCUSSION: The findings suggest that loneliness may play a role in increased cannabis use frequency and problematic alcohol and cannabis use. Strategies to reduce loneliness and increase social connection may have downstream effects on reducing the risk of problematic alcohol and cannabis use among young adults.