Introduction: The first Danish Helicopter Emergency Medical Service (HEMS) was introduced May 1st2010. The implementation was associated with lower 30-day mortality in severely injured patients. Theaim of this study was to assess the long-term effects of HEMS on labour market affiliation and mortalityof trauma patients.

Methods: Prospective, observational study with a maximum follow-up time of 4.5 years. Traumapatients from a 5-month period prior to the implementation of HEMS (pre-HEMS) were compared withpatients from the first 12 months after implementation (post-HEMS). All analyses were adjusted for sex,age and Injury Severity Score.

Results: Of the total 1994 patients, 1790 were eligible for mortality analyses and 1172 (n = 297 preHEMSand n = 875 post-HEMS) for labour market analyses. Incidence rates of involuntary earlyretirement or death were 2.40 per 100 person-years pre-HEMS and 2.00 post-HEMS; corresponding to ahazard ratio (HR) of 0.72 (95% confidence interval (CI) 0.44–1.17; p = 0.18). The HR of involuntary earlyretirement was 0.79 (95% CI 0.44–1.43; p = 0.43). The prevalence of reduced work ability after three yearswere 21.4% vs. 17.7%, odds ratio (OR) = 0.78 (CI 0.53–1.14; p = 0.20). The proportions of patients on socialtransfer payments at least half the time during the three-year period were 30.5% vs. 23.4%, OR = 0.68 (CI0.49–0.96; p = 0.03). HR for mortality was 0.92 (CI 0.62–1.35; p = 0.66).

Conclusions: The implementation of HEMS was associated with a significant reduction in time on socialtransfer payments. No significant differences were found in involuntary early retirement rate, long-termmortality, or work ability.