Amish Study Explores Roots Of Bipolar Disorder

Symptoms of bipolar illness were found to occur more often among Amish youth who had at least one parent with bipolar illness, according to researchers who following the youngsters for 10 years. None of the children, however, was diagnosed before puberty.

“As our population of high-risk Amish youths aged, there was a shift from the more internalizing symptoms to those that are more often thought of as manic-like behaviors: high energy, decreased sleep, excessive and loud talking, and problems in concentration,” wrote Jon Shaw, M.D., a professor of psychiatry and behavioral science and project psychiatrist in the Affective Disorders Project at the University of Miami, and four colleagues. Their study appeared in the November Journal of the American Academy of Child and Adolescent Psychiatry.

The Old Order Amish community has drawn the interest of researchers in several fields because it is a largely endogamous group that has separated itself culturally and genetically from the general population. Members may leave the community from time to time, but they don't allow conversion, said Shaw. “There's been no new DNA since they came to America.”

The sample contrasted 14 families, including 110 children, in which at least one parent had been diagnosed with bipolar I disorder with 13 matched control families with 112 children. At the study's 10-year mark, 41 percent of the children with a bipolar parent exhibited some risk for bipolar disorder, compared with 16 percent of those without a bipolar parent. Some of the 55 clinical features the researchers recorded were also reported by the control families, suggesting a lack of reporting bias on the part of parents.

Children of bipolar I parents had significantly more frequent reports of anxiety, poor attention, excitability, hyperalertness, labile moods, somatic complaints, stub-bornness, and role impairments in school—all of which were noted in the study's previous seven-year report. Five additional items reached significance by the 10th year of the study: high energy, decreased sleep problems, excessive talking, loud talking, and problems with thinking or concentration. Symptoms less common at 10 years than at seven were low energy, anger dyscontrol, fearfulness, and sensitivity.

No children below the age of 12 and only two postpubertal youngsters met DSM-IV criteria for bipolar I disorder.

“We don't see the subtype of pediatric mania we see in other populations,” said Shaw in an interview. Nor was there early onset of aggression, rage reactions, sexual promiscuity, classical attention-deficity/hyperactivity disorder, or mood or emotional dysregulation, he said.