Family history predicts presence and course of psychiatric disorders

Family history of a psychiatric condition is generally known to increase an individual's risk of developing that condition, according to background information in the article. "However, there is a need to go further and test whether family history is also associated with clinical features of the disorder thought to represent a continuum of seriousness among individuals who meet criteria for diagnosis," the authors write.

Barry J. Milne, Ph.D., of University of Auckland, New Zealand, and colleagues studied 981 residents of Dunedin, New Zealand, born in 1972 or 1973. Participants were enrolled in the Dunedin Study at age 3 and followed up through age 32. Between 2003 and 2005, family history data were collected about each individual's biological parents, grandparents and siblings older than 10 years. Four psychiatric disorders were studied: major depressive episode, anxiety disorder, alcohol dependence and drug dependence.

"In general, we found that associations showed a consistent direction of effect across all four disorders: (1) family history was associated with the presence vs. absence of disorder for all four disorder types; (2) family history was associated with a recurrent course for all four disorders (but not significantly for women with depression); (3) family history was associated with worse impairment for all four disorders (but not significantly for depression and drug dependence); and (4) family history was associated with greater service use for all four disorders (but not significantly for anxiety disorders)," the authors write.

The results suggest implications for researchers who wish to study genetic forms of a disorder and also for clinicians treating psychiatric conditions, the authors note.

From a public health perspective, family history may be useful for determining which patients will have the poorest prognosis," they conclude. "For example, among those with depression, anxiety disorder, alcohol dependence and drug dependence, a family history screen may help determine whose illness will recur, whose illness will cause the greatest impairment and who will be the most likely to use treatment resources. Thus, family history may identify a subgroup in need of primary or early intervention, and for whom treatments appropriate for recurrent, highly disabling disorder may be needed."

More information: Arch Gen Psychiatry. 2009;66[7]:738-747.

Source: JAMA and Archives Journals (news : web)