Emergency Department Visits in a Cohort of Persons with Substance Use: Incorporating the Role of Social Networks.

BACKGROUND: Frequent emergency department (ED) visits often suggest inappropriate use for low acuity needs and multiple comorbidities, including substance use disorders.

OBJECTIVE: This study examines associations of individuals and their social networks with high frequency ED use among persons reporting substance use.

METHODS: Information was obtained from interview responses from the first 6-month follow-up visit of a longitudinal. Prevalence ratios for the outcome of high frequency ED visits (≥2 in 6 months) were determined with a generalized linear model, log link, Poisson distribution and robust standard errors.

RESULTS: Of 653 participants, 131 (20%) had ≥2 ED visits. In multivariable analysis, greater likelihood of high frequency ED visits over 6 months was associated with being homeless (PR: 1.58; 95% CI: 1.19, 2.10), taking ≥3 medications (PR: 1.58; 95% CI: 1.19, 2.10) and having had a hospitalization over the same period (PR: 4.33; 95% CI: 3.26, 7.56). Among social network factors, lower likelihood of high frequency visits was associated with each increasing year of mean alter age (PR: 0.98; 95% CI: 0.6, 0.99) and greater likelihood with having received health-related informational support from ≥2 alters (PR: 1.62; 95% CI: 1.04, 2.53). Conclusions/Importance: Social network factors may play an important role in ED use. Interventions to promote health behaviors through social influence may be helpful in reducing high frequency ED visits.