Assessment of Heatwave Impacts on Cause-Specific Emergency Department Attendances in Queensland, Australia

Abstract

Background/Aim: To examine the impacts of heatwaves on emergency department attendances (EDAs) in Queensland, Australia. Methods: A quasi-Poisson generalized additive model was used to quantify the effects of heatwaves on cause-specific EDAs in eight cities of Queensland, Australia, including Brisbane, Cairns, Longreach, Mackay, Mount Isa, Rockhampton, Toowoomba and Townsville. The study period was from 01/01/2013 to 31/12/2015. Possible confounders including seasonality and long-term trend, day of week, and relative humidity were controlled in the model. The city-specific results were meta-analyzed to get the pooled result for the whole Queensland. Based on the findings of our previous work, heatwave was defined as three or more consecutive days when the mean temperature was ≥ 95th percentile of the mean temperature across the whole study period. Results: During heatwave periods, EDAs for a wide range of diseases increased appreciably in Queensland, including nutritional and metabolic diseases (RR:1.181, 95% CI:1.040, 1.342), injury, poisoning and certain other consequences of external causes (RR:1.092, 95% CI:1.039,1.147), diseases of the nervous system (RR:1.091, 95% CI:1.021, 1.166), diseases of the skin and subcutaneous tissue (RR:1.079, 95% CI:1.002, 1.162), diseases of the musculoskeletal system and connective tissue (RR:1.069, 95% CI:1.004, 1.140), endocrine, mental and behavioral disorders (RR:1.062, 95% CI:1.006, 1.120), certain infectious and parasitic diseases (RR:1.058, 95% CI:1.011, 1.108), diseases of the circulatory system (RR:1.055, 95% CI:1.014,1.097), diseases of the genitourinary system (RR:1.046, 95% CI:1.004, 1.090), and diseases of the ear and mastoid process (RR:1.041, 95% CI:1.006,1.077). Heatwave effects on total EDAs varied across different cities, and the greatest effect was observed in Townsville (RR:1.082, 95% CI:1.026, 1.140), followed by Rockhampton (RR:1.071, 95% CI: 1.024, 1.120), Mount Isa (RR:1.056, 95% CI: 0.975, 1.144), Toowoomba (RR:1.031, 95% CI:0.974, 1.092), Cairns (RR:1.029 , 95% CI:0.991, 1.069), Brisbane (RR:1.018, 95% CI:0.999, 1.038), Mackay (RR:1.016, 95% CI:0.970, 1.063), and Longreach (RR:0.977, 95% CI:0.851, 1.121). The effect of heatwaves on total EDAs in the rural region (RR:1.039, 95% CI:1.010, 1.069) was similar to that in the urban region (RR:1.035, 95% CI:1.003, 1.068). Conclusions: EDAs for a wide range of diseases increased during heatwave periods. As climate change progresses, EDAs in Queensland may increase in the future, requiring the Queensland Government to develop effective public health strategies to adapt to climate change.