Prevalence and heritability of alcohol use disorders in 18-year old Swedish twins

Malin Hildebrand Karlén; Ann-Sophie Lindqvist Bagge; Ulf Berggren; Claudia Fahlke; Peter Andiné; Sabrina Doering; Sebastian Lundström

doi:10.1177/14550725221090383

Prevalence and heritability of alcohol use disorders in 18-year old Swedish twins

Nordisk Alkohol Nark. 2023 Aug;40(4):391-405. doi: 10.1177/14550725221090383. Epub 2023 May 24.

Authors

Malin Hildebrand Karlén¹, Ann-Sophie Lindqvist Bagge², Ulf Berggren³, Claudia Fahlke⁴, Peter Andiné⁵, Sabrina Doering⁶, Sebastian Lundström⁷

Affiliations

¹ Centre for Ethics, Law and Mental Health, Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, University of Gothenburg, Gothenburg, Sweden Department of Forensic Psychiatry, National Board of Forensic Medicine, Gothenburg, Sweden Department of Psychology, University of Gothenburg, Gothenburg, Sweden.
² Department of Psychology, University of Gothenburg, Gothenburg, Sweden Centre for Ethics, Law and Mental Health, Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, University of Gothenburg, Gothenburg, Sweden.
³ Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, University of Gothenburg, Gothenburg, Sweden.
⁴ Department of Psychology, University of Gothenburg.
⁵ Centre for Ethics, Law and Mental Health, Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden Forensic Psychiatric Clinic, Sahlgrenska University Hospital, Gothenburg, Sweden Department of Forensic Psychiatry, National Board of Forensic Medicine, Gothenburg, Sweden.
⁶ Centre for Ethics, Law and Mental Health, Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, University of Gothenburg, Gothenburg, Sweden.
⁷ Centre for Ethics, Law and Mental Health, Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, University of Gothenburg, Gothenburg, Sweden Gillberg Neuropsychiatry Centre, University of Gothenburg, Gothenburg, Sweden.

Abstract

Background: Heritability of alcohol use disorders (AUDs) varies widely, with reported estimates of 30-78% in twin studies. This variation might be due to methodological differences (e.g., using different thresholds for AUDs, age differences between samples). Aim: To investigate the heritability of AUDs in a nation-wide sample of male and female twins in late adolescence (18 years). Participants: The study is based on data from 8,330 18-year-old Swedish monozygotic (MZ) and dizygotic (DZ) twins from the Child and Adolescent Twin Study (Sweden). Method: Univariate sex-limitation twin analyses were performed using (a) total AUDIT score, (b) different AUDIT cut-offs (AUDIT-10: potentially harmful alcohol use and most likely alcohol dependent ; AUDIT-C: potential hazardous alcohol consumption/active alcohol use disorders), and (c) a risk-group classification for alcohol dependence based on AUDIT total score. Results: Prevalence of potential hazardous alcohol consumption/active alcohol use was 57.1%, and for potentially harmful alcohol use prevalence was 26.5%. Prevalence was higher among females (59.0% and 31.1% respectively) than males (54.4% and 20.0% respectively). Overall, the results of the univariate model fitting indicated that there were qualitative sex differences in the genetic and environmental influences on AUDs, with generally moderate heritability estimates ranging between 0.37 and 0.50. Discussion: At odds with previous research, a harmful/hazardous drinking pattern was more common in this age group among females than a low-risk drinking pattern (where males were overrepresented). Heritability estimates were moderate throughout all measures and cut-offs, with equally high contributions from shared and non-shared environment. Sex-limitation models revealed qualitative sex differences for AUDs, suggesting that different genetic and/or environmental factors influence variation in AUDs in males and females.

Keywords: adolescence; alcohol use disorder; gender; hazardous alcohol consumption; risk groups.