Australia’s remarkable decline in suicide deaths since the late 1990s reflects a decline in the lethality of attempts, researchers say.
By calculating the rate of suicide attempts and deaths by the most common methods, the University of Melbourne researchers found lethality declined by 57%, from 12% of all attempts resulting in death in 1994 to 5% of attempts resulting in death in 2007.
Furthermore, the researchers were able to account for at least some of the increase in attempt failures, including changes to catalytic converters in motor vehicles which have reduced carbon monoxide emission levels.
“This study identified changes in method-specific lethality as a critical driver of Australia’s decline in suicide deaths since 1997,” they wrote.
The study looked at nearly 32,000 suicide deaths and more than 378,000 suicide attempts, as well as the methods used (42% hanging, 19% motor vehicle exhaust, poisoning 13% and firearms 11%).
Motor vehicle exhaust deaths followed an inverted U-shaped trend, with the decline in recent years being due to decreases in lethality of attempts, in line with gradual penetration of new, safer vehicles in the Australian market, a “successful (if unintended) strategy of preventing suicide by means restriction”, the authors said.
Hanging attempts increased, from 0.9 per 100,000 in 1994 to 4.9/100,000 in 2007, but lethality declined, the analysis found.
The researchers said there were several possible explanations including that people who made the attempts “did so with waning levels of intent and vigour”, possibly reflecting acts of self-harm in which the intention was not to die or the rise in interest in asphyxia games.
A decline in firearm deaths was due to a decline in attempts, which began before the gun buy-back program in the wake of the 1996 Port Arthur massacre, the researchers said.
They acknowledged that data on suicide attempts was “imperfect” but said identification of reasons for positive trends in reducing fatalities was a step toward devising strategies to sustain and extend them.
Meanwhile, on the approach to World Suicide Prevention Day on 10 September, Griffith University has announced the world’s first master’s degree in suicide prevention, the Master of Suicidology.
As first appeared in Medical Observer, 7 September 2012