Hot weather has been linked to an increased suicide risk for young Australians.
A study out of News South Wales found for every one degree rise in the daily mean temperature (DMT) emergency department (ED) visits by young people for suicidal behaviours increased by 1.3 percent.
Lead author Dr Cybele Dey, a psychiatrist and conjoint lecturer at UNSW Sydney, said researchers studied more than 55,000 suicidality presentations made by young people, aged 12 to 24, at EDs in New South Wales during the warmer months of November to March, from 2012 to 2019.
Dr Dey said the increase in presentations occurred across a full range of temperatures and on single hot days, not only during heatwaves when factors like poor sleep were more likely to be an issue.
“The impact on the very first day where the temperature is hotter than usual is just as bad as each subsequent day, and the effect starts at a more moderate temperature than expected,” she said.
“This is not about concern about climate change affecting the mental health of young people, this is about hot weather itself affecting them.”
Dr Dey said, as an example, on days with a 24-hour mean temperature of 21.9°C , which was the average DMT for the study period, there was an average of 45.7 youth suicidality presentations statewide.
She said at that level, presentations were already 4.7 percent higher than they would be at a cooler DMT of 18.3°C, the state’s average for spring.
“By a DMT of 25.2°C, the base for a heatwave, presentations were about nine percent higher than at the spring DMT, and about 15 percent higher by a DMT of 30°C, which is reflective of extreme heat.”
Dr Dey said researchers, from UNSW, Sydney Children’s Hospitals Network, NSW Ministry of Health, NSW Health, The University of Sydney and Queensland Children’s Hospital, controlled for long-term trends, holiday periods and school days when analysing the data.
She said further investigation was needed on the link between heat and youth suicidality, to confirm if higher temperatures were causing the increase, as they suspected, or were simply coinciding with it.
Read the full study: Youth suicidality risk relative to ambient temperature and heatwaves across climate zones: A time series analysis of emergency department presentations in New South Wales, Australia
