Suicide is one of the leading causes of death worldwide but what causes it is still not well understood. Mental-health problems are an important risk factor but most people with a mental-health problem do not think about killing themselves. There is strong evidence that people's experiences contribute more towards their mental-health problems than their genes and that bad experiences in people's childhood are linked to more thoughts about, or attempts at, killing oneself in later life. However, there has been less research into this than into genetic factors or mental-health problems. A team of researchers led by Ronny Bruffaerts from Gasthuisberg University Hospital in Belgium studied an international sample of 55,299 people asking them about their experiences in childhood and whether they had thought about, or tried to kill themselves. They found that bad experiences in childhood were associated with an increased risk of suicide attempts and thoughts of suicide. Sexual and physical abuse, especially during adolescence, were consistently the strongest risk factors.
Bruffaerts, Ronny ... [et al] - Childhood adversities as risk factors for onset and persistence of suicidal behaviour. British Journal of Psychiatry, July 2010, 197(1), 20-27