Abstract
IMPORTANCE: Although anxiety disorders are known to run in families, the relative contribution of genes and environment is unclear. Patterns of sex-specific transmission of anxiety may point to different pathways in how parents pass anxiety disorders down to their children; however, the association of parent and offspring sex with the transmission of anxiety disorders has not been previously studied. OBJECTIVE: To examine whether the transmission of anxiety from parents to children is sex specific. DESIGN, SETTING, AND PARTICIPANTS: This cross-sectional family study recruited participants from the general population (enriched for familial risk of mood disorders) in Nova Scotia, Canada, from February 1, 2013, to January 31, 2020. EXPOSURES: Anxiety disorder in the same-sex or opposite-sex parent. MAIN OUTCOMES AND MEASURES: Semistructured interviews were used to establish lifetime diagnoses of anxiety disorder in parents and offspring. The association between anxiety disorder in the same-sex or opposite-sex parent and anxiety disorders in the offspring was tested with logistic regression. RESULTS: A total of 398 offspring (203 female offspring with a mean [SD] age of 11.1 [3.7] years and 195 male offspring with a mean [SD] age of 10.6 [3.1] years) of 221 mothers and 237 fathers participated in the study. Anxiety disorders in the same-sex parent (odds ratio [OR], 2.85; 95% CI, 1.52-5.34; P = .001) were associated with increased rates of anxiety disorders in the offspring, whereas anxiety disorders in the opposite-sex parent (OR, 1.51; 95% CI, 0.81-2.81; P = .20) were not. Sharing a household with a same-sex parent without anxiety was associated with lower rates of offspring anxiety (OR, 0.38; 95% CI, 0.22-0.67; P = .001), but the presence of an opposite-sex parent without anxiety was not (OR, 0.96; 95% CI, 0.56-1.63; P = .88). CONCLUSIONS AND RELEVANCE: In this cross-sectional study of families, an association between the same-sex parent's anxiety disorder and anxiety disorders in offspring suggests an environmental mechanism, such as modeling. Future studies should establish whether treating parents' anxiety may protect their children from developing an anxiety disorder.