All cause and cause specific mortality among individuals imprisoned for driving under the influence of alcohol and drugs in Norway (2000-2016)

The risk of premature death is particularly high among individuals convicted of alcohol and drug related crimes compared to both the general population, and individuals convicted of other criminal offences. Driving under the influence (DUI) of alcohol and psychoactive drugs is included in the category of alcohol and drug related crimes. Using data from The Norwegian Prison Release Study (nPRIS), we aim to investigate all cause and cause specific mortality among individuals imprisoned for DUI, and investigate factors associated with mortality.

In this retrospective cohort study data from nPRIS on all imprisoned individuals (2000-2016) were linked with data from the Norwegian Cause of Death Registry in the same period. ICD-10 codes registered as the underlying cause of death were classified into relevant groups for description of causes of death. We calculated crude mortality rates (CMRs) per 100 000 person-years (PY).

Of the 96 856 individuals in the cohort, 8 056 had died at end of 2016, and the all-cause CMR was 891/100 000 PY. In total, 28 393 (29.3%) individuals had one or more imprisonments for DUI during the observation period. The proportion of women was 9.5% (n=2 688).

During the observation period, 10.5% (n=2 989) of those with DUI-imprisonment died (CMR = 1 098/100 000 PY) and the mean age at death was 51 years. External causes of death accounted for 47% (n=1 409) of all deaths. The most frequent external causes of death were overdose (21.9%, n=632) and suicide (8.4%, n=242). Transportation accidents accounted for 4.2% (n=120). Internal causes of death accounted for 46% (n=1 376) of all deaths. The most prevalent internal causes of death were circulatory diseases (15.7%, n=454) and cancer (14%, n=404).

Preliminary results show that individuals imprisoned for DUI are at high risk of premature death and many die of external causes.