Pooled analysis of all-cause and cause-specific mortality among Nordic military veterans following international deployment.

OBJECTIVES: To investigate all-cause and cause-specific mortality risks, including deaths from external, cardiovascular and cancer causes, among deployed Nordic military veterans in comparison to the general population in each country. DESIGN: Pooled analysis. SETTING: Denmark, Norway, Finland and Sweden. PARTICIPANTS: Military veterans deployed between 1990 and 2010 were followed via nationwide registers and compared with age-sex-calendar-year-specific rates in the general population using pooled standardised mortality ratios (SMRs). MAIN OUTCOMES: All-cause and cause-specific mortality retrieved from each country's Causes of Death Register, including deaths from external, cardiovascular and cancer causes. RESULTS: Among 83 584 veterans 1152 deaths occurred of which 343 were from external causes (including 203 suicides and 129 traffic/transport accidents), 134 from cardiovascular causes and 297 from neoplasms. Veterans had a lower risk of death from any cause (pooled SMR 0.58, 95% CI 0.52 to 0.64), external causes (0.71, 95% CI 0.64 to 0.79), suicide (0.77, 95% CI 0.67 to 0.89), cardiovascular causes (0.54, 95% CI 0.46 to 0.64) and neoplasms (0.78, 95% CI 0.70 to 0.88). There was no difference regarding traffic/transport accidents for the whole period (1.10, 95% CI 0.92 to 1.31) but the pooled point estimate was elevated, though not statistically significant, during the first 5 years (1.17, 95% CI 0.89 to 1.53) but not thereafter (1.01, 95% CI 0.77 to 1.34). For all other causes of death, except suicide, statistically significantly lower risk among veterans was observed both during the first 5 years and thereafter. For suicide, no difference was observed beyond 5 years. Judged from the country-specific SMR estimates, there was a high degree of consistency although statistically significant heterogeneity was found for all-cause mortality. CONCLUSIONS: Nordic military veterans had lower overall and cause-specific mortality than the general population for most outcomes, as expected given the predeployment selection process. Though uncommon, fatal traffic/transport accidents were an exception with no difference between deployed military veterans and the general population.

Violent crime among Swedish military veterans after deployment to Afghanistan: a population-based matched cohort study.

OBJECTIVE: To investigate the incidence of violent crime conviction among Swedish military veterans after deployment to Afghanistan versus non-deployed comparators. The main outcome was first conviction of a violent crime, retrieved from the Swedish National Council for Crime Prevention Register until December 31, 2013. METHODS: This was a cohort study of military veterans identified through personnel registers regarding deployment to Afghanistan between 2002 and 2013 (n = 5894). To each military veteran, up to five non-deployed comparators identified via the Military Service Conscription Register were matched by age, sex, conscription year, cognitive ability, psychological assessment, self-reported mental health, body mass index, antidepressants/anxiolytics prescriptions and self-harm (fully matched comparators; n = 28 895). Multivariable adjustment was made for substance abuse and previous health care visits with psychiatric diagnoses. An additional comparator group matched only for age, sex and conscription year was also used (age-sex-matched comparators; n = 29 410). RESULTS: During 21 898 person-years of follow-up (median = 3.6 years) there were 26 events among deployed military veterans compared with 98 in non-deployed fully matched comparators [12 vs 9 per 10 000 person-years, adjusted hazard ratio (aHR) 1.36; 95% confidence interval (CI) 0.88-2.10]. Among non-deployed age-sex-matched comparators there were 170 violent crime convictions (16 per 10 000 person-years; aHR 0.85; 95% CI 0.56-1.29). Factors associated with greater risk of violent crime convictions were younger age, lower scores on cognitive ability tests and psychological assessment, and convictions preceding deployment. CONCLUSION: The violent crime conviction rate after returning from military deployment to Afghanistan was not different compared with non-deployed comparators in individuals without history of violent crime convictions.

Marriage and divorce after military deployment to Afghanistan: A matched cohort study from Sweden.

AIM: To investigate the probability of marriage and divorce among Swedish military veterans deployed to Afghanistan relative to non-deployed matched comparators. STUDY DESIGN AND SETTING: Matched cohort study in Sweden. PARTICIPANTS: Military veterans were identified through Swedish military personnel registers regarding foreign deployments, and comparators from the Military Service Conscription Register (1969-2013). Of 1,882,411 eligible conscripts, 7041 had served in Afghanistan at some point in time between 2002 and 2013. To each military veteran, up to 5 non-deployed comparators who underwent conscription were matched by age, sex, psychological assessment, cognitive ability, psychiatric history and social characteristics. After matching there were 4896 (82%) unmarried and 1069 (18%) married deployed military veterans. The main outcome was marriage or divorce after deployment to Afghanistan. Data on marital status were retrieved from Statistics Sweden until December 31, 2014. RESULTS: During a median follow-up of 4.1 years after deployment of married individuals, 124 divorces were observed among deployed military veterans and 399 in the matched non-deployed comparator cohort (277 vs. 178 per 10,000 person-years; adjusted hazard ratio 1.61, 95%CI 1.31-1.97). During a median follow-up of 4.7 years after deployment in the unmarried cohort, 827 new marriages were observed among deployed military veterans and 4363 in the matched non-deployed comparators cohort (399 vs. 444 per 10,000 person-years; adjusted hazard ratio 0.89, 95%CI 0.83-0.96). CONCLUSION: Military veterans were more likely to divorce and less likely to marry after deployment compared with matched non-deployed comparators.

Suicide and all-cause mortality in Swedish deployed military veterans: a population-based matched cohort study.

OBJECTIVE: To investigate suicide and mortality risk in deployed military veterans versus non-deployed comparators who had gone through military conscription testing. DESIGN: Population-based matched cohort study. SETTING: Sweden. PARTICIPANTS: Participants were identified from the Military Service Conscription Register and deployment status from the Swedish Military Information Personnel Register. Of 1.9 million conscripts, 21 721 had deployed at some time between 1990 and 2013 (deployed military veterans). Non-deployed comparators were matched to deployed military veterans in two ways: (1) by cognitive ability, psychological assessment, mental health, body mass index, sex, birth-year and conscription-year (carefully matched), with further adjustment for exercise capacity and suicide attempt history; and (2) by sex, birth-year and conscription-year (age- and sex-matched). MAIN OUTCOME: Suicide retrieved from the Swedish National Patient and Causes of Death Register until 31 December 2013. RESULTS: During a median follow-up of 12 years, 39 and 211 deaths by suicide occurred in deployed military veterans (n=21 627) and carefully matched non-deployed comparators (n=107 284), respectively (15 vs 16/100 000 person-years; adjusted HR (aHR) 1.07; 95% CI 0.75 to 1.52; p=0.72) and 329 in age- and sex-matched non-deployed comparators (n=108 140; 25/100 000 person-years; aHR 0.59; 95% CI 0.42 to 0.82; p=0.002). There were 284 and 1444 deaths by suicide or attempted suicides in deployed military veterans and carefully matched non-deployed comparators, respectively (109 vs 112; aHR 0.99; 95% CI 0.88 to 1.13; p=0.93) and 2061 in age- and sex-matched non-deployed comparators (158; aHR 0.69; 95% CI 0.61 to 0.79; p<0.001). The corresponding figures for all-cause mortality for carefully matched non-deployed comparators were 159 and 820 (61 vs 63/100 000 person-years; aHR 0.97; 95% CI 0.82 to 1.15; p=0.71) and 1289 for age- and sex-matched non-deployed comparators (98/100 000 person-years; aHR 0.62; 95% CI 0.52 to 0.73; p<0.001). CONCLUSION: Deployed military veterans had similar suicide and mortality risk as non-deployed comparators after accounting for psychological, psychiatric and physical factors. Studies of mental health in deployed veterans need to adjust for more factors than age and sex for comparisons to be meaningful.