Factors associated with drowning in Portugal, 2019-2023

Abstract Worldwide, mortality from drowning amounted to 236.000 individuals in 2019, corresponding to 8% of the total global mortality, making drowning the third leading cause of death from unintentional injuries and a universal public health problem. Portugal has a coastal zone of 950 km long, with 658 bathing waters and, in 2023, 157 people died due to drowning. This work aims to determine the factors associated with drownings that occurred in Portugal, between 2019 and 2023. This epidemiological descriptive-analytical study used the National Maritime Authority database, regarding the users of the portuguese coastal zone who suffered maritime incidents between 2019 and 2023. SPSS was used for statistical analysis and the results of the Poisson regression models are presented as adjusted prevalence ratios (APR) with 95% confidence intervals, according to individual (sex, age group and nationality), temporal (period of the week and day) and environmental (maritime department and beach surveillance status) variables. The total sample was 406 drownings and 15 860 other maritime incidents. Overall, the frequency of drownings in Portugal was higher in men (APR=1.393, 95%CI=1.130-1.717, p=.002), in the >55y age group (APR=1.780, 95%CI=1.005-3.152, p=.048), in foreigners (APR= 1.293, 95%CI=1.037-1.612, p=.022), on weekends (APR=1.299, 95%CI=1.063-1.586, p=.010), in the afternoon (APR=1.584, 95%CI=1.127-2.226, p=.008) and on unsupervised beaches (APR=2.436, 95%CI=1.958-3.029, p<.001) in comparison with users who suffered other maritime incidents. Individual, temporal and environmental factors are associated with a higher frequency of drownings in Portugal. Despite the limitation of the study that only includes users suffering maritime incidents and not all users of the portuguese coastal zone, our results allow a preliminary characterization of the drowning profile in Portugal and can contribute to the design of preventive strategies and policies to address this public health problem. Key messages • This study shows that there are individual, temporal and environmental factors strongly associated with a higher frequency of drownings in Portugal. • Portugal has a large coastal zone and the characterization of a drowning profile is the first step for the development of prevention strategies in order to oppose drowning morbidity and mortality.