Depression signals start of mental disorder in bipolar patients’ children
medwireNews: Depression may be the first sign of a bipolar spectrum disorder in children with bipolar parents, indicate prospective study findings.
Results from the Dutch Bipolar Offspring Study, now with 12 years of follow up, show that a depressive episode preceded the child's diagnosis in 88% of cases and occurred an average of 5 years before the first manic or hypomanic episode.
"In almost all participants with bipolar spectrum disorders, the illness started with a depressive episode," explain Manon Hillegers (University of Utrecht, the Netherlands) and colleagues.
The Dutch researchers found that 72% of the 108 children who were studied from adolescence to adulthood developed a lifetime DSM-IV axis I disorder, with 13% developing a bipolar spectrum disorder. Of the latter, 3% had bipolar I disorder (BD-I) and 8% bipolar II disorder (BD-II).
"Even after 12 years of follow-up, from adolescence into adulthood, bipolar I disorder was rare among bipolar offspring," Hillegers et al write in The American Journal of Psychology.
However, the risk for developing severe and recurrent mood disorders and other psychopathology was high, they report. Indeed, the prevalence of developing a lifetime DSM-IV diagnosis of any mood disorder at 12-year follow up was 54%.
The Dutch Offspring study is one of four cohort studies prospectively evaluating the development of psychiatric illnesses in the children of patients with BD-I or BD-II. The rationale behind these studies is that bipolar disorder has a strong genetic predisposition and studying the children of those affected may help understand how the disorder develops and initially manifests.
The mean age at onset of the first mood episode in children diagnosed with a bipolar spectrum disorder was 14.6 years, with hypomania occurring at a median of 17.3 years and mania at a median of 20.2 years. Five (29%) children experienced their first depressive episode before 12 years of age.
Of the 54% that developed any mood disorder, almost a quarter developed a bipolar spectrum disorder during follow up and a third had recurrent unipolar depression. This equates to 31% of the bipolar children having a recurrent mood disorder.
"Early intervention appears indicated to enhance normal development and prevent the onset of mood disorders," say Hillegers and team.
They conclude: "Future follow-up of this and the other adult offspring bipolar cohorts is essential to determine whether recurrent mood disorders in bipolar reflect the early stages of bipolar disorder."
By Sara Freeman, medwireNews Reporter