Divorce
The Genetics of Divorce
Genetic predispositions for psychiatric disorders are linked to divorce.
Posted October 8, 2024 Reviewed by Abigail Fagan
Key points
- Divorce is a complex phenomenon, shaped by multiple determinants.
- Research has established a link between psychological disorders and divorce.
- Psychological disorders may facilitate divorce. Likewise, the stress of divorce may facilitate disorders.
Divorce is common worldwide. It is also consequential. Marital status has been linked to a range of psychiatric morbidities. Much of the effort to understand the links between divorce and psychiatric disorders has focused on examining whether disorders are likely to cause divorce, or vice versa. Indeed, evidence supports the notion that the vulnerabilities and coping challenges associated with psychiatric disorders may over time undermine marital stability. Likewise, the stress associated with divorce procedures may facilitate the emergence of psychiatric disorders. Divorce has been shown to predict the onset of several disorders, including drug and alcohol abuse.
While divorce and psychological disorders may influence each other, a third causal possibility also exists: that certain genetic predispositions may contribute to both risk of divorce and risk of psychiatric morbidity
A recent (2024) study by Jessica Salvatore of Rutgers University and colleagues sought to test this hypothesis. The researchers collected data on individuals from Swedish population-based registers. The database consisted of all individuals born in Sweden between 1950 and 1980 to Swedish-born parents, followed through the end of 2018. This included over 2,800,000 individuals (mean age at end of follow-up: 51.7 years old; age range: 38 to 68). Data were obtained on patterns of family genetic risk scores (FGRSs)—personalized measures of genetic risk inferred from diagnoses in relatives regarding 10 psychiatric disorders (major depression, anxiety disorders, obsessive-compulsive disorder, bipolar disorder, schizophrenia, anorexia nervosa, alcohol use disorder, drug use disorder, attention-deficit/hyperactive disorder, and autism spectrum disorder).
A total of 592,232 of the study’s participants experienced divorce (with a sizable minority experiencing multiple divorces). The average length of first marriages ending in divorce was 14.7 years. Among individuals who experienced divorce, the most common psychiatric disorders before divorce were major depression, anxiety disorders, and alcohol use disorders.
The results of this ambitious effort were instructive. First, divorced individuals had substantially higher FGRSs than the respective population average for all 10 disorders. By contrast, individuals who were in stable marriages and those who never married had FGRSs lower than the respective population average across all 10 disorders. In addition, results showed that “FGRSs for most disorders increased as the number of divorce transitions increased.”
The researchers analyzed the potential role of sex in the equation. They found that FGRSs for the 10 disorders were elevated among both divorced females and divorced males. However, “compared with divorced males, divorced females had significantly higher FGRSs such than divorced males.” They interpret these results to suggest that “the traits/behaviors and interpersonal stressors associated with genetic predispositions for these disorders...may be less well tolerated in wives than in husbands.”
Further, FGRSs for most disorders were elevated in both those who divorced multiple times and those who ended up in stable second marriages. However, compared with individuals with stable second marriages, those without stable second marriages had higher FGRSs across all disorders (except anorexia). Never-married individuals also tended to have higher FGRSs than stably married individuals but lower than divorced individuals. Thus, the authors conclude: “Even within a population of divorced individuals, genetic predispositions for psychiatric disorders are associated with the ability to form and maintain a second marriage."
Finally, the researchers found that individuals who divorced a spouse with diagnosed psychological disorders tended to have higher FGRSs across the 10 psychiatric disorders, compared with individuals who divorced a spouse without such diagnoses. This finding was surprising given the authors’ hypothesis that divorcing a troubled spouse may be a sign of psychological health, rather than vulnerability.
The authors concede that associations between FGRSs and marital status do not necessarily imply a direct causal relationship. Further work is needed to understand the mechanisms underlying the patterns observed in this study. Several possible pathways may link genetic predispositions and divorce. For example, the sub-clinical traits and behaviors associated with a disorder may mediate the influence of genetic predispositions on divorce. High-FGRS individuals may provoke troubled behaviors in their spouses, which in turn may contribute to divorce. Moreover, high-FGRS individuals may be prone to selecting high-FGRS partners whose symptoms may increase the risk of divorce. High-FGRS individuals may also actively seek out environments where divorce is more common or acceptable. Future research is needed to disentangle the high FGRs-divorce risk link.
The authors summarize their main findings thus: “In the Swedish population, divorce is associated with elevated FGRSs for 10 major psychiatric disorders. These elevations were particularly pronounced among divorced females compared with divorced males, among individuals who did not go on to have a stable second marriage, and among individuals with multiple divorce transitions. There were particularly notable elevations in FGRSs for internalizing disorders and substance use disorders. As a set, the results from this study provide some of the most comprehensive evidence concerning the genetic landscape of psychiatric disorders related to divorce.”
So, is divorce genetic? Not quite. Genes, it should be remembered, do not create traits and behavioral habits but rather potentialities for such. The path from genetic vulnerabilities to actual life outcomes (from genotype to phenotype in psychology speak) is usually complex, and influenced by non-genetic factors such as early (and current) environmental conditions, stress, and chance, among others. Thus, it is incorrect to say that divorce is in the genes. The risk for divorce, however, is now properly understood to be strongly genetic.