Anxiety sensitivity as a moderator of the relationship between trait anxiety and illicit substance use

Anxiety and substance use problems are common and often comorbid, and past research has shown that young adults in particular are especially at risk for developing these disorders. To further delineate the relationship between anxiety and substance use, the current study evaluated anxiety sensitivity (AS)-a cognitive vulnerability factor-as a moderator of the association between trait anxiety and illicit substance use in a large sample of young adults (N = 845; M = 18.7 years, SD = 1.0). It was hypothesized that AS would moderate the association between trait anxiety and illicit substance use, such that trait anxiety would significantly predict illicit substance use among those with high, but not low, AS. Consistent with prediction, a significant trait Anxiety × AS interaction was found, χ²(5) = 29.38, p < .001. Specifically, analyses of simple slopes revealed that for the high-AS group, as trait anxiety increased, so did frequency of illicit substance use (odds ratio [OR] = 1.03, p = .005; 95% confidence interval [CI] [1.01, 1.06]). The slope for the low AS was not significant (OR = 0.98, p = .100; 95% CI [0.95, 1.01]). Results also showed significant moderation effects for the AS physical concerns and cognitive concerns facets but not AS social concerns. These findings suggest that AS may be an important cognitive vulnerability that may help to identify those at particular risk for substance use, and that interventions should target AS reduction in anxiety-prone individuals to reduce and prevent substance abuse.