Mortality trends and the impact of exposure on Australian coastal drowning deaths, 2004–2021

Abstract

ObjectiveThe aim of this study is to characterise Australian coastal drowning trends and evaluate impact of exposure on drowning risk. MethodsDescriptive epidemiological analysis of unintentional fatal drowning occurring July 2004-June 2021 at Australian coastal sites (beaches, rock platforms, bays, harbours, offshore locations etc.). Total population, exposed-person and exposed-person-time rates per 100,000 population were calculated by age, sex, socio-economic status, remoteness category and pre-submersion activity. Annual trends were assessed using joinpoint regression. Exposure-based rates used estimates from Surf Life Saving Australia’s National Coastal Safety Survey. ResultsThe cumulative unintentional coastal fatal drowning rate was 0.43 per 100,000 Australian residents (95%CI: 0.41–0.45) and did not change throughout the study period (p=0.289). The exposed-person rate was 0.67 per 100,000 coastal visitors (95%CI: 0.62–0.72), and there were 0.55 coastal drowning deaths per 10 million coastal visitor hours (95%CI: 0.51–0.59). Men, older people and residents of lower socio-economic and remote areas had higher drowning rates; rock fishing and scuba diving had the highest activity exposure-based rates. ConclusionsEducation- and policy-based coastal safety interventions should focus on identified risk factors to reduce annual coastal drowning rates. Implications for Public HealthExposure-based risk measurements are important for developing and prioritising interventions; assessments based on counts or total population measures alone may misinform prevention efforts.