Accounting for the association between childhood maltreatment and alcohol-use disorders in males: a twin study

Abstract

Background: An association between childhood maltreatment and subsequent alcohol abuse and/or dependence (AAD) has been found in multiple studies of females. Less is known about the association between childhood maltreatment and AAD among males, and the mechanisms that underlie this association in either gender. One explanation is that childhood maltreatment increases risk for AAD. An alternative explanation is that the same genetic or environmental factors that increase a child's risk for being maltreated also contribute to risk for AAD in adulthood.

Method: Lifetime diagnosis of AAD was assessed using structured clinical interviews in a sample of 3527 male participants aged 19-56 years from the Virginia Adult Twin Study of Psychiatric and Substance Use Disorders. The sources of childhood maltreatment-AAD association were estimated using both a matched case-control analysis of twin pairs discordant for childhood maltreatment and bivariate twin modeling.

Results: Approximately 9% of participants reported childhood maltreatment, defined as serious neglect, molestation, or physical abuse occurring before the age of 15 years. Those who experienced childhood maltreatment were 1.74 times as likely to meet AAD criteria compared with males who did not experience childhood maltreatment. The childhood maltreatment-AAD association largely reflected environmental factors in common to members of twin pairs. Additional exploratory analyses provided evidence that AAD risk associated with childhood maltreatment was significantly attenuated after adjusting for measured family-level risk factors.

Conclusions: Males who experienced childhood maltreatment had an increased risk for AAD. Our results suggest that the childhood maltreatment-AAD association is attributable to broader environmental adversity shared between twins.

Fig. 1

Risk of alcohol abuse and/or dependence (AAD) relative to controls (odds ratios) in monozygotic twins discordant for childhood maltreatment (■), dizygotic twins discordant for childhood maltreatment () and in unrelated pairs, i.e. those who had experienced childhood maltreatment versus no no childhood maltreatment (□). An odds ratio of 1 indicates no difference in AAD risk between cases and controls.

Fig. 2

Path diagram for association between childhood maltreatment–alcohol abuse and/or dependence (AAD). A, Additive genetic factors; C, common environmental factors; E, individual-specific environmental factors. The model shown is for one twin in a pair. For model identification, the corresponding childhood maltreatment and AAD loadings from A1, C1, and E1 are equated. Thresholds and means were estimated but not shown.