Predicting a Second Suicide Attempt

After a suicide attempt the individual is usually followed to see if a second attempt is likely.  Factors assessed include estimates of likely intent, the presence of psychiatric disorder, or use of a violent method in the first attempt.  The risk of suicide after an unsuccessful attempt is about 10%, according to a number of studies.  Psychiatrists at the Karolinska Institute, Sweden, have analyzed their records, looking for clues that might allow the number of successful second attempts to be reduced.  Their findings are published in the British Medical Journal.    

The participants in the study were 48,649 people admitted to hospital between 1973-1982 after attempting suicide.  They were followed for 21-31 years, during which time 12% of them (5,740) committed suicide successfully.  The researchers looked for possible links between the methods employed in the first and second attempts.

Successful suicides were more common during the first year after the initial attempt. Attempted suicide by poisoning was the most common method (84% of attempters). The likelihood of a second attempt being successful was calculated for each method used, and expressed as the hazard ratio, using poisoning as the ‘standard’, or 1.0.

Compared with poisoning, it was found that hanging, drowning, firearms, jumping from a height, and gassing were methods used for first attempts as well as successful follow-up attempts.  As an example, a man who had made an unsuccessful first attempt by hanging has a 6.2-times greater likelihood of hanging himself subsequently than if he had first tried to poison himself.  (The class ‘hanging’ also includes strangulation and suffocation.)  The hazard ratios obtained for other methods were: drowning – 4.0, firearms or explosives – 3.2, jumping from a height – 3.2, and gassing – 1.8.

The authors of the analysis advise that their findings have important practical implications.  The 5 methods (particularly hanging) for attempted suicide are strongly related to subsequent successful suicides.  This should be taken into account in evaluating suicide risk and planning aftercare after an attempt, if the numbers of successful suicides are to be reduced.