Association Between Lifetime Posttraumatic Stress Disorder and Past Year Alcohol Use Disorder Among American Indians/Alaska Natives and Non-Hispanic Whites

Background: Posttraumatic stress disorder (PTSD) and alcohol use disorder disproportionately impact certain populations including American Indians/Alaska Natives (AIAN). While PTSD and alcohol use disorder have been studied both separately and in tandem, less is known about the association in AIAN. The objective was to examine the association between lifetime PTSD and past year alcohol use disorder among AIAN and non-Hispanic Whites (NHW). Methods: Data come from the 2012 to 2013 U.S. National Epidemiologic Survey on Alcohol and Related Conditions-III. We used logistic regression to estimate odds of AUD among adults with and without PTSD by race. Results: A total of 19,705 participants, of whom 511 were AIAN and 19,194 were NHW, were included in this study. The percentage of PTSD among AIAN was 22.9% (n=117) compared to 11.7% (n=2,251) in NHW (p-value <0.0001). The percentage of past year alcohol use disorder among AIAN was 20.2% (n=103) compared to 14.2% (n=2,725) in NHW (p-value <0.0001). The percentage of comorbid past year alcohol use disorder with lifetime PTSD among AIAN was 6.5% (n=33) compared to 2.4% (n=457) in NHW (p-value <0.0001). Regarding the joint distribution of PTSD and AUD, AIAN men have greater than 3 times the percentage compared to NHW men (9.5% vs. 3.1%). When stratifying by race (after adjusting for age, sex, depression, and education), among AIAN, the odds of past year alcohol use disorder with (vs. without) lifetime PTSD were 1.76 (95% CI 1.07, 2.90) and among NHW, the odds were 1.59 (95% CI 1.41, 1.80). Conclusions: PTSD is significantly associated with alcohol use disorder in the study populations. Despite a lack of pre-PTSD measures of alcohol use disorder, these findings show a trend indicating that AIAN exposed to PTSD are more burdened with alcohol use disorder compared to NHW in the general U.S. population.