Symptom profiles and illness course among Anabaptist and Non-Anabaptist adults with major mood disorders

Kelly E. Gill, Stephanie A. Cardenas, Layla Kassem, Thomas G. Schulze, Francis J. McMahon

Anabaptists comprise large and growing Amish and Mennonite populations with a unique genetic heritage and cultural background. Little is known about the symptoms and course of major mood disorders in Anabaptists. Even less is known about the impact of potential moderators on symptom severity and course. A sample of Amish and Mennonite participants with bipolar, recurrent unipolar, or schizoaffective bipolar disorder (n = 155) were systematically evaluated with a well-validated instrument. Cases were compared with non-Anabaptist participants (n = 155) matched for age, sex, and psychiatric diagnosis and evaluated by the same methods. Despite substantial cultural differences, the profile of manic and depressive symptoms during illness episodes did not significantly differ between the two groups. Alcohol use disorder (AUD) was significantly less frequent among Anabaptists, and was associated with more major depressive episodes and more hospitalizations for major depression in Anabaptist, but not non-Anabaptist participants. Lifetime history of head injury showed a trend toward association with more episodes of major depression in both Anabaptist and non-Anabaptist groups that did not withstand multiple test correction. The presentation of a highly heritable psychiatric illness such as bipolar disorder does not differ in cases drawn from genetically unique Anabaptist populations. However, alcohol comorbidity, head injury, and their effects on illness course suggest some differences that deserve further investigation.