The blunt truth: The role of marijuana in PTSD after intentional traumatic injury.

Kern J.; Wilson C.; Joshi S.; Ghio M.; O'Neill K.; Reese J.; Babb R.; Emili P.; Williams A.; Seamon M. et al. · Injury · 2026

**Background & Methods** This prospective cohort study examined relationships between PTSD and marijuana use in survivors of intentional traumatic injury admitted to an urban, level-1 trauma center between October 2019 and July 2024. Among 105 intentionally injured patients with complete follow-up data, 69 who screened negative for PTSD at baseline were included in the analysis, with assessments at baseline and 6- or 12-month follow-up using standardized PTSD screening and self-reported substance use measures. **Key Findings** • Patients who screened positive for PTSD at follow-up demonstrated significantly higher marijuana use both at baseline (29% vs 3%, p=0.002) and at follow-up (42% vs 13%, p=0.007) compared to PTSD-negative patients. • In multivariable logistic regression adjusting for demographic and injury characteristics, follow-up PTSD screening positivity was associated with 7.1 times greater odds of marijuana use at follow-up (p=0.007, 95% CI: 1.7-29.5). • PTSD-positive patients demonstrated worse quality of life across all PROMIS-29 domains compared to PTSD-negative patients (p≤0.01), suggesting broader functional impairment beyond substance use patterns. **Dosage & Administration** Not reported. **Safety & Adverse Effects** Not reported. The study examined marijuana use as an outcome variable rather than as a therapeutic intervention, therefore adverse effects of cannabis were not assessed or documented. **Evidence Quality** This is a Level III prognostic/epidemiological study with notable limitations. The small sample size (n=69 after exclusions) limits generalizability, and the study demonstrates association rather than causation—it remains unclear whether PTSD drives increased marijuana use, marijuana use increases PTSD risk, or whether both reflect unmeasured confounding factors. The reliance on self-reported substance use and screening instruments rather than diagnostic assessments may introduce bias. The single-center urban academic setting may not represent diverse trauma populations. The study's primary strength is its prospective design with structured follow-up in a well-characterized trauma cohort. The authors appropriately conclude that screening for marijuana use could identify patients at psychological risk, though the directional relationship between PTSD and cannabis use requires further investigation.

More recent cannabis research