Abstract
Background: There have been multiple changes to the Arms Act 1983 in Aotearoa New Zealand (NZ) which have subsequently been associated with reductions in firearm-related suicide. In response to the worst mass shooting in NZ's history, stricter regulations on firearm ownership were introduced in 2020.
Objective: To describe both individual- and population-level risks for firearm-related offenses, hospitalizations, and deaths in NZ and to summarize the annual costs (in U.S. dollars).
Design: Retrospective cohort study.
Setting: New Zealand.
Participants: All NZ residents (individual-level data, 2000 to 2018; population-level data, 2000 to mid-2024).
Measurements: Rates per million people for firearm-related hospitalizations and deaths secondary to assault, accidents, and suicide were examined. Years of life lost (YLLs) and age-adjusted rates were calculated as well as rate ratios (RRs) for hospitalization or death with 95% CIs.
Results: Firearm-related hospitalizations and deaths due to self-harm or accidents decreased between 2000 and 2018, but rates due to assault increased 2.5-fold between 2014 and 2018. Hospitalizations due to accidents were higher for children aged 0 to 14 years than for persons aged 15 years or older (RR, 1.11 [95% CI, 0.97 to 1.27]). Māori (RR, 2.88 [CI, 2.30 to 3.61]) and Pacific Peoples (RR, 2.14 [CI, 1.57 to 2.92]) had higher rates of hospitalization due to assault than persons in the European/Other group. The average cost of firearm-related hospitalizations was $871 000 per year, and YLLs yielded a total mortality cost of $189 million per year.
Limitation: The results include only firearm-related injuries and deaths resulting in hospitalization and do not include firearm-related injuries that did not result in hospitalization or other burdens of illness related to firearms.
Conclusion: The high costs of firearm-related injuries underscore the importance of improving firearm-related harm reduction in NZ. This will depend on maintaining and strengthening current firearm access restrictions and could be enhanced through firearm education.