Cannabis abuse and serious suicide attempts.
OBJECTIVE
To compare the relationship between cannabis abuse/dependence and risk of medically serious suicide attempts in individuals making serious suicide attempts and randomly selected comparison subjects.


METHODS
Case-control comparison.


METHODS
Cases, a general hospital; controls, the local community.


METHODS
Cases were 302 consecutive individuals making medically serious suicide attempts; 1028 randomly selected control subjects.


METHODS
DSM-III-R mental disorder diagnoses; measures of socio-demographic characteristics and childhood and family experiences.


RESULTS
Of those making serious suicide attempts, 16.2% met DSM-III-R criteria for cannabis abuse/dependence at the time of the attempt, compared with 1.9% of comparison subjects (OR = 10.3; 95%CI, 5.95-17.8, p < 0.0001). Risks of serious suicide attempt were significantly related to a series of socio-demographic and childhood characteristics, and to mental disorders that were co-morbid with cannabis abuse/dependence. When the association between cannabis abuse/dependence and suicide attempt risk was controlled for socio-demographic factors, childhood factors and concurrent psychiatric morbidity, there was a marginally significant association (OR = 2.0; 95%CI, 0.97-5.3, p < 0.06) between cannabis abuse/dependence and serious suicide attempt risk.


CONCLUSIONS
These results suggested that much of the association between cannabis abuse/dependence and suicide attempt risk arose because: (a) individuals who develop cannabis abuse/dependency tend to come from disadvantaged socio-demographic and childhood backgrounds which, independently of cannabis abuse, are associated with higher risk of suicide attempt, or (b) because cannabis abuse/dependence is co-morbid with other mental disorders which are independently associated with suicidal behaviour. Nevertheless, the possibility remains that cannabis abuse/dependence may make an independent contribution to risk of serious suicide attempt, both directly and through the possible effects of cannabis abuse on risk of other mental disorders.
Beautrais
A L
AL
Department of Psychological Medicine, Christchurch School of Medicine, New Zealand. suicide@chmeds.ac.nz
Joyce
P R
PR
Mulder
R T
RT
D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000368:Aged; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D008297:Male; D002189:Marijuana Abuse / Q000453:epidemiology*; D008875:Middle Aged; D009520:New Zealand / Q000453:epidemiology; D012111:Residence Characteristics; D012307:Risk Factors; D017678:Sex Distribution; D012923:Social Class; D013406:Suicide, Attempted / Q000706:statistics & numerical data*