Empirically defined subtypes of alcohol dependence in an Irish family sample

Sintov, Nicole D.; Kendler, Kenneth S.; Young-Wolff, Kelly C.; Walsh, Dermot; Patterson, Diana G.; Prescott, Carol A.

doi:10.1016/j.drugalcdep.2009.11.003

« Previous Next »Drug and Alcohol Dependence
Volume 107, Issue 2 , Pages 230-236, 1 March 2010

Empirically defined subtypes of alcohol dependence in an Irish family sample

Nicole D. Sintov
- Department of Psychology, University of Southern California, Los Angeles, CA 90089, USA
Kenneth S. Kendler
- Virginia Institute for Psychiatric and Behavioral Genetics, Department of Psychiatry, Virginia Commonwealth University, Richmond, VA, USA
Kelly C. Young-Wolff
- Department of Psychology, University of Southern California, Los Angeles, CA 90089, USA
Dermot Walsh
- Health Research Board, Dublin, Ireland
Diana G. Patterson
- Shaftsbury Square Hospital, Belfast, Northern Ireland, United Kingdom
Carol A. Prescott
- Department of Psychology, University of Southern California, Los Angeles, CA 90089, USA
- Corresponding author at: Department of Psychology/SGM 501, University of Southern California, 3620 South McClintock Avenue, Los Angeles, CA 90089-1061, USA. Tel.: +1 213 740 2314; fax: +1 213 746 9082.

Received 8 December 2008; received in revised form 6 October 2009; accepted 4 November 2009.

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.

Keywords: Alcoholism typology, Alcohol dependence, Alcoholism subtypes, Latent class analysis