Previous research has highlighted a clustering of suicidal behaviour among families. Ping Qin and colleagues from Aarhus University, Denmark, assessed whether family history of completed suicide and mental illness that results in admission to hospital were risk factors for suicide, and whether these factors interact.
Using data from four Danish longitudinal registers, the investigators identified 4262 people who had committed suicide aged 945 years during 198197, and 80,238 matched controls.
Individuals with a history of family suicide were two and a half times more likely to commit suicide than people without a family history of suicide; correspondingly, a family history of psychiatric illness (requiring hospital admission) increased suicide risk by around 50%, but only for individuals who did not have a psychiatric history. A history of family suicide and psychiatric history were independent risk factors for suicide, but the effect was strongest when they were combined.
Ping Qin comments: "With respect to attributable risk, we have shown that a family suicide history and family psychiatric history accounted for 2.25% and 6.80% of suicides, respectively. These estimates were made after adjustment for other risk factors and would be larger if exposures in other relatives, family history of suicide attempts, and family history of psychiatric disorders that did not result in admission to hospital had been included."
She concludes: "The inclusion of familial suicidal history in the assessment of suicide risk is important, even though people with a family history of suicide are only a small proportion of the total number of pe
'"/>
Contact: Richard Lane
richard.lane@lancet.com
44-20-7424-4949
Lancet
10-Oct-2002