Racial/ethnic disparities in the dose-response relationship between syndemic risk factors and increased gun carrying odds among male high school students in the United States.

Objective: Substance use, mental health, and violence are co-occurring risks associated with gun carrying among adolescents. Using a syndemic framework, we examined the co-occurrence and cumulative effect of these risk factors on gun carrying in male adolescents and potential racial/ethnic disparities. Methods: We analyzed 2019-2023 Youth Risk Behavior Survey data with weighted multiple logistic regression models, controlling for age and sexual orientation. A syndemic risk factor variable was created by summing exposures to substance use, mental health, and victimization/violence. Interaction terms were tested, and models were stratified by race/ethnicity. A penalized maximum likelihood estimation (PMLE) regression was also applied to address potential instability due to the rarity of the outcome. Results: In multiple regression models, a significant dose-response relationship was found between the number of syndemic risk factors and the odds of gun carrying. Compared with male adolescents reporting 0-1 syndemic risk factors, the odds of gun carrying was more than five times higher among those with 2-3 syndemic risk factors (Adjusted Odds Ratio (AOR): 5.1, 95 % CI: 4.0, 6.6) and almost 17 times higher among those with 4+ syndemic risk factors (AOR: 17.3, 95 % CI: 12.9, 23.2). Stratified analyses revealed stronger effects among Black and Hispanic adolescents. Results were similar with PMLE regression. Conclusions: The odds of gun carrying increased as the number of syndemic risk factors increased, with notable racial/ethnic disparities. Understanding the syndemic risk factors associated with gun carrying and the disparities that exist is crucial for developing targeted prevention interventions.