Mood instability in childhood as a precursor to bipolar disorder

Over the 1- to 4-year period of follow-up, mood instability was associated with poor prognosis indicators in high-risk youth: Being younger, having younger ages at first symptom onset, being diagnosed with other specified BD (vs. major depression), and having more complex patterns of comorbid disorders. Mood instability tracked closely with levels of mania, depression, and global functioning over the follow-up. There was a temporal pathway between a diagnosis of other specified bipolar disorder at intake and higher levels of mood instability at follow-up, which in turn predicted higher levels of parent/child conflict. High levels of mood lability may lead to isolation from peers and tension within family relationships, which may fuel further children’s expressions of frustration, rage, depression, or impulsive behavior.

Youth with higher levels of mood instability required more complex medication regimens over 1 year than did those with lower instability. There was an overall reduction in mood instability as children aged (or spent more time in treatment). Over the 1- to 4-year follow-up, family-focused therapy was associated with longer intervals prior to new mood episodes than was enhanced usual care, but reductions in mood instability were independent of the type of psychosocial treatment assigned to children.

The participants in this study could not be followed long enough to determine whether levels of mood instability were associated with the later development of syndromal BD. Other studies, however, have documented this relationship. Large-scale longitudinal studies of high-risk children find that measures of mood lability – along with early onset manic symptoms, depression, anxiety, and a family history of mania or hypomania – can be combined to calculate the risk that any individual child will develop BD I or II over the next 5-8 years.^2,5

Clinicians should include measurement of the severity and psychosocial determinants of persistent mood shifts in youth under their care, particularly those with a family history of BD. Mood instability is associated with more severe symptom trajectories, more social isolation, and greater distress and conflict within the family. It may require a greater intensity of both pharmacological and psychosocial treatments to treat existing symptoms and functional impairments, and to prevent further mood deterioration.

Dr. Miklowitz is Distinguished Professor of Psychiatry and Biobehavioral Sciences, University of California, Los Angeles, Semel Institute for Neuroscience and Human Behavior. He is the author of “The Bipolar Disorder Survival Guide, 3rd Ed.” (New York: Guilford Press, 2019) and “Bipolar Disorder: A Family-Focused Treatment Approach, 2nd Ed” (New York: Guilford Press, 2010). He has no conflicts of interest to disclose. Contact Dr. Miklowitz at dmiklowitz@mednet.ucla.edu.

References

1. Bonsall MB, et al. Nonlinear time-series approaches in characterizing mood stability and mood instability in bipolar disorder. Proc Biol Sci. Mar 7 2012;279(1730):916-24. doi: 10.1098/rspb.2011.1246.

2. Hafeman DM, et al. Toward the definition of a bipolar prodrome: Dimensional predictors of bipolar spectrum disorders in at-risk youths. Am J Psychiatry. 2016;173(7):695-704. doi: 10.1176/appi.ajp.2015.15040414.

3. Miklowitz DJ, et al. Mood instability in youth at high risk for bipolar disorder. J Am Acad Child Adol Psychiatry. 2022 Mar 17;S0890-8567(22)00118-6. doi: 10.1016/j.jaac.2022.03.009.

4. Gerson AC, et al. The Children’s Affective Lability Scale: a psychometric evaluation of reliability. Psychiatry Res. Dec 20 1996;65(3):189-98. doi: 10.1016/s0165-1781(96)02851-x.

5. Birmaher B, et al. A risk calculator to predict the individual risk of conversion from subthreshold bipolar symptoms to bipolar disorder I or II in youth. J Am Acad Child Adol Psychiatry. 2018;57(10):755-63. doi: 10.1016/j.jaac.2018.05.023.