The Association of Life Stress With Substance Use Symptoms: A Network Analysis and Replication

A growing body of evidence highlights the role of life stress as a risk factor for the development and relapse of substance use disorders (SUDs), but the relationship of life stress with the interactions among SUD symptoms is overlooked. The current study investigated the role of life stress in symptom networks of 3 different SUDs-alcohol, tobacco, and drug use-using the U.S. representative data from the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC) I and II (N = 34,653). The symptom networks were estimated using the Ising model and l1-regularziation with model selection based on the Extended Bayesian Information Criterion. We examined the association of stress with 2 network characteristics: the network connectivity and the network structure. In addition, we applied bootstrap routines to examine the stability of our results and tested whether our findings of Wave 1 replicated in Wave II of the NESARC. For alcohol and drug use symptoms, but not for tobacco use symptoms, greater network connectivity (which is related to psychiatric severity and prognosis) was associated with the number of stressors. In contrast, the structure of SUD symptom networks remained stable regardless of the level of stress, which indicated that the order of central nodes in the symptom networks was not significantly associated with stress. Altogether, our findings suggest that there is a quantitative (i.e., greater connectivity), but not qualitative (i.e., structure), difference in alcohol and drug use symptom relationships associated with life stress.