IntroductionVeterans residing in Northern Ireland (NI) likely experience higher levels of co-occurring lifetime trauma exposure and associated co-occurring mental health symptoms, due to the Troubles. As NI veterans have been subject to little exploration it is difficult to know how to support them. This exploratory study explored the co-occurrence of mental health symptoms as a function of co-occurring traumatic experiences.MethodsTwo latent class analyses (LCA) were conducted on NI veteran data (n = 609). One LCA factored endorsements of 16-lifetime traumatic events, with a separate LCA exploring the co-occurrence of symptoms across six mental health domains. Mental health symptom classes were considered as a function of trauma classes, military-specific variables, gender and age.ResultsThree trauma classes were identified: High Multi Trauma (10.84%); High Combat/Conflict (47.62%); Moderate Combat Conflict (41.54%), and three mental health symptom classes: High Co-occurring Mental Health (19.38%); High Depression Moderate Anxiety/Alcohol (24.63%); Moderate Alcohol/Normative (55.99%). Significant predictors of High Co-occurring Mental Health class membership were UDR service, ‘Worst’ military trauma and High Multi Trauma class membership. Both combat classes had a negative relationship with the High Co-occurring Mental Health. Predictors of the High Depression Moderate Anxiety/Alcohol class were High Multi Trauma class membership and UDR service, with Age and Moderate Combat Class membership having a negative relationship.DiscussionNI veterans could be labelled as ‘traumatised’ due to high levels of combat/conflict exposure, yet the two combat classes seemed unrelated to membership of poorer mental health classes. UDR membership indicated that living in one’s theatre of war could have mental health implications. It was concerning that 45% experienced some co-occurring mental health symptoms with 19% experiencing the poorest symptoms. Hazardous alcohol use appeared unrelated to poor mental health. Further research is needed, utilising robust methods. No clinical inferences are to be made from this exploratory study.