Moderators of the relationship between alcohol dependence and suicide and medically serious suicide attempts: analyses of Canterbury Suicide Project data.
BACKGROUND
Preliminary data indicate that age, gender, and mood disorder moderate the association of alcohol dependence and suicide. The purpose of this study was to evaluate potential moderators of the relationship between alcohol dependence and suicide and medically serious suicide attempts by using case-control data gathered in the Canterbury region of New Zealand for the Canterbury Suicide Project.


METHODS
Data on 193 suicide decedents, 240 medically serious suicide attempters, and 984 community controls, all age 18 and over, were gathered by using psychological autopsy methodology. Multinomial logistic analyses were used to compare the two case groups to controls on demographic and diagnostic variables. Moderating effects were evaluated based on significant statistical interactions of predictors with alcohol dependence.


RESULTS
The association of alcohol dependence and suicide (but not medically serious attempts) was amplified with increased age. Neither mood disorder nor gender moderated the relationship between alcohol dependence and suicide. Increased age amplified the association of mood disorder and suicide, whereas decreased age strengthened the association of mood disorder and medically serious suicide attempts.


CONCLUSIONS
Older age may serve as a marker for a construct (e.g., aggression/impulsivity) that underlies the failure to mature out of alcoholism, or a late-onset subtype of alcoholism prone to negative affect, accounting for the association of older age and suicide in this population. Older age also may merely reflect longer duration of the deleterious effects of alcoholism.
Conner
Kenneth R
KR
Center for the Study and Prevention of Suicide, University of Rochester Medical Center, New York, USA. kenneth_conner@urmc.rochester.edu
Beautrais
Annette L
AL
Conwell
Yeates
Y
D000293:Adolescent; D000328:Adult; D000437:Alcoholism / Q000453:epidemiology* / Q000523:psychology; D016009:Chi-Square Distribution; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D001523:Mental Disorders / Q000453:epidemiology* / Q000523:psychology; D008875:Middle Aged; D009520:New Zealand / Q000453:epidemiology; D016017:Odds Ratio; D012307:Risk Factors; D013405:Suicide / Q000523:psychology / Q000706:statistics & numerical data; D013406:Suicide, Attempted / Q000523:psychology / Q000706:statistics & numerical data