Epidemiology of firearm injuries in Sweden

Background: Gun violence is a global health problem. Population-based research on firearm-related injuries has been relatively limited considering the burden of disease. The aim of this study was to analyze nationwide epidemiological trends of firearm injuries. Methods: This is a retrospective nationwide epidemiological study including all patients with firearm injuries from the Swedish Trauma Registry (SweTrau) during the period 2011 and 2019. Registry data were merged with data from the Swedish National Council for Crime Prevention and the Swedish Police Authority. Results: There were 1010 patients admitted with firearm injuries, 96.6% men and 3.4% women, median age 26.0 years [IQR 22.0–36.3]. The overall number of firearm injuries increased on a yearly basis (P < 0.001). The most common anatomical injury location was lower extremity (29.7%) followed by upper extremity (13.8%), abdomen (13.8%), and chest (12.5%). The head was the most severely injured body region with a median abbreviated injury scale (AIS) of 5 [IQR 3.2–5]. Vascular injuries were mainly located to the lower extremity (42%; 74/175). Majority of patients (51.3%) had more than one anatomic injury location. The median hospital length of stay was 3 days [IQR 2–8]. 154 patients (15.2%) died within 24 h of admission. The 30-day and 90-day mortality was 16.7% (169/1010) and 17.5% (177/1010), respectively. There was an association between 24-h mortality and emergency department systolic blood pressure < 90 mmHg [OR 30.3, 95% CI 16.1–56.9] as well as the following injuries with AIS ≥ 3; head [OR 11.8, 95% CI 7.5–18.5], chest [OR 2.3, 95% CI 1.3–4.1], and upper extremity [OR 3.6, CI 1.3–10.1]. Conclusions: This nationwide study shows an annual increase of firearm-related injuries and fatalities. Firearm injuries affect people of all ages but more frequently young males in major cities. One in six patients succumbed from their injuries within 30 days with most deaths occurring within 24 h of hospital admission. Given the impact of firearm-related injuries on society additional research on a national level is critical.