title: Empirically defined subtypes of alcohol dependence in an Irish family sample.
abstract: Alcohol dependence (AD) is clinically and etiologically heterogeneous. The goal of this study was to explore AD subtypes among a sample of 1221 participants in the Irish Affected Sib Pair Study of Alcohol Dependence, all of whom met DSM-IV criteria for AD. Variables used to identify the subtypes included major depressive disorder, antisocial personality disorder, illicit drug dependence (cannabis, sedatives, stimulants, cocaine, opioids, and hallucinogens), nicotine dependence, the personality traits of neuroticism and novelty seeking, and early alcohol use. Using latent class analysis, a 3-class solution was identified as the most parsimonious description of the data. Individuals in a Mild class were least likely to have comorbid psychopathology, whereas a severe class had highest probabilities of all comorbid psychopathology. The third class was characterized by high probabilities of major depression and higher neuroticism scores, but lower likelihood of other comorbid disorders than seen in the severe class. Overall, sibling pair resemblance for class was stronger within than between classes, and was greatest for siblings within the severe class, suggesting a stronger familial etiology for this class. These findings are consistent with the affective regulation and behavioral disinhibition subtypes of alcoholism, and are in line with prior work suggesting familial influences on subtype etiology.
authors.affiliation: Department of Psychology, University of Southern California, Los Angeles, CA 90089, USA.
authors.forename: Nicole D
authors.initials: ND
authors.lastname: Sintov
authors.forename: Kenneth S
authors.initials: KS
authors.lastname: Kendler
authors.forename: Kelly C
authors.initials: KC
authors.lastname: Young-Wolff
authors.forename: Dermot
authors.initials: D
authors.lastname: Walsh
authors.forename: Diana G
authors.initials: DG
authors.lastname: Patterson
authors.forename: Carol A
authors.initials: CA
authors.lastname: Prescott
mesh_terms: D000328:Adult; D000367:Age Factors; D017668:Age of Onset; D000428:Alcohol Drinking / Q000523:psychology*; D000437:Alcoholism / Q000145:classification* / Q000175:diagnosis / Q000453:epidemiology* / Q000523:psychology; D000987:Antisocial Personality Disorder / Q000175:diagnosis / Q000453:epidemiology* / Q000523:psychology; D015897:Comorbidity; D003865:Major Depressive Disorder / Q000175:diagnosis / Q000453:epidemiology* / Q000523:psychology; D039721:Diagnostic and Statistical Manual of Mental Disorders; D005190:Family / Q000523:psychology; D005260:Female; D006801:Humans; D008297:Male; D009660:Northern Ireland / Q000453:epidemiology; D010555:Personality Inventory; D011569:Psychiatric Status Rating Scales; D012307:Risk Factors; D012494:Sampling Studies; D012720:Severity of Illness Index; D035781:Siblings / Q000523:psychology; D019966:Substance-Related Disorders / Q000175:diagnosis / Q000453:epidemiology* / Q000523:psychology; D011795:Surveys and Questionnaires