LAUSR

OBJECTIVE The phenotype of patients who suffer fatal traumatic brain injury (TBI) is poorly characterized. The authors examined the external causes, contributing diseases, and preinjury medication in adult patients with fatal TBI in a nationwide Finnish cohort. METHODS Deaths caused by TBIs in Finland were examined among decedents aged ≥ 16 years during 2005-2020 from the national Cause of Death Registry. Usage of prescription medications prior to TBI was studied using medication purchase data from the Social Insurance Institution of Finland. RESULTS The cohort consisted of 71,488,347 person-years, 821,259 total deaths, and 14,630 TBI-related deaths during 2005-2020, of which 67% (n = 9792) occurred in men. Women were older than men among those who suffered TBI-related death (mean age 77.2 ± 17.1 vs 64.5 ± 19.5 years, p < 0.0001). The overall crude incidence rate of fatal TBIs was 20.5/100,000 person-years (28.1/100,000 in men and 13.2/100,000 in women). TBI was the cause of death in 1.8% of all deaths in the Finnish population during the study years, but in patients aged 16-19 years, TBIs caused more than 17% of all deaths. The most common external cause of fatal TBI was a fall (70%), followed by poisoning or toxic effects (20%) and violence or self-harm (15%) overall. In men, the order of the most common causes of fatal TBI was similar to overall results (64%, 25%, and 19%, respectively), while in women, the most common cause was a fall (82%), followed by complications in healthcare (10%) and poisoning or toxic effects (9%). Cardiovascular diseases, psychiatric diseases, and infections were the most common diseases contributing to death. Blood pressure (lowering) medications were the most common type of medications used before fatal TBI. CNS medications were the second most common medication group. In the context of fatal TBI in Europe, Finland remains at the upper end of fatal TBI incidence. CONCLUSIONS TBI is a common cause of death in young adults, whereas the incidence of fatal TBI becomes increasingly higher with age in Finland. Cardiovascular diseases and psychiatric conditions were the most common diseases related to death, with opposite age trends. Healthcare facility complications were an alarmingly common cause of death in women with fatal TBI.