Americans with bipolar are more likely than Europeans to marry someone with a similar diagnosis, according to a study by Robert M. Post, MD, of the Bipolar Collaborative Network, Bethesda, Maryland, and the department of psychiatry and behavioral sciences, George Washington University. Post and colleagues recruited volunteers with bipolar I from four cities in the USA and three cities in Europe to fill out a questionnaire which included information about their families and medical history.
31% of respondents in the United States had a spouse with a mental illness diagnosis, compared with only 9% of the Europeans (Netherlands and Germany). Diagnoses included unipolar depression, bipolar disorder, a serious suicide attempt or suicide, alcohol or drug abuse, or other psychiatric illness such as anxiety disorder, panic attacks, eating disorders, attention-deficit disorder, behavioral problems, obsessive compulsive disorder, autism, etc.
Offspring of the study participants were found to have significantly more mental illness diagnoses if both parents had such illnesses. In addition, the study found that the parents of the study participants showed more “assortive mating” (both spouses with mental illness) in the USA (21%) than in Europe (6%).
The study relied only on patient-reported data, and did not include information about the family members’ disease severity and age at onset. Nonetheless, it strongly suggests that importance should be placed on identifying and treating young people at risk of mental illness, especially in the United States.
Post RM, Altshuler LL, Kupka R, et al. More assortative mating in US compared to European parents and spouses of patients with bipolar disorder: Implications for psychiatric illness in the offspring [published online August 11, 2018]. Eur Arch Psychiatry Clin Neurosci. doi:10.1007/s00406-018-0934-y