Trajectories of alcohol misuse among the UK Armed Forces over a 12-year period

Aim To identify the main trajectories of alcohol misuse among UK military personnel from 12 years after the start of the Iraq war (2003) and the factors associated with each trajectory. Design Longitudinal cohort study with three phases of data collection (2004-06, 2007-09 and 2014-16). Setting United Kingdom. Participants Serving and ex-serving personnel of the UK Armed Forces (n = 7111) participating at Phase 1 and at least one follow-up phase of the King's Centre for Military Health Research (KCMHR) cohort study. Measurements Trajectories of alcohol misuse were derived from scores using the Alcohol Use Disorders Identification Test (AUDIT-10) over three data collection phases. Demographic and military characteristics were collected and, among the key covariates, post-traumatic stress disorder (PTSD) was measured using the PTSD checklist (PCL-C) and childhood interpersonal stress and violence was measured using items from the Adverse Childhood Experiences questionnaire. Findings Five trajectories of alcohol misuse were identified, including 'no misuse' (n = 2249, 31.6%) and 'hazardous' (n = 3398, 47.8%), 'harmful' (n = 832, 11.7%), 'severe-to-hazardous' (n = 258, 5.3%) and 'severe' (n = 374, 3.6%) drinking. Substantial changes were evident only among severe drinkers, where more than half reduced over the study period. The factors most strongly associated with belonging to harmful/severe drinking classes were young age, male gender and childhood adversities and antisocial behaviour. Severe drinkers at Phase 1 were more likely to report probable PTSD and shorter military careers and were less likely to serve as Officers. Persistent severe drinkers were less likely to serve in the RAF compared to the Army and were more likely to be reserves. Not misusing alcohol was also associated with reserve status and having left service. Conclusions In a cohort of approximately 7000 UK military personnel, trajectories of alcohol misuse appeared stable between 2004 and 2016. More than half of severe drinkers made substantial improvements over the period, but 68% of the cohort continued to drink hazardously or harmfully. Lack of change for the majority of the sample signals the need for strategies to address alcohol misuse and its cultural and psychosocial drivers.