Abstract
Objective
Research and clinical interest in irritability have been on the rise in recent years. Yet several questions remain about the status of irritability in psychiatry, including whether irritability can be differentiated from other symptoms, whether it forms a distinct disorder, and whether it is a meaningful predictor of clinical outcomes. In this paper we try to answer these questions by reviewing the evidence on how reliably irritability can be measured and its validity.
Method
We combine a narrative and systematic review and meta-analysis of studies. For the systematic review and meta-analysis, we searched studies in Pubmed and Web of Science based on preselected criteria (i.e., irritability as a predictor of future psychiatric outcomes). One hundred sixty-three papers were reviewed, and 24 were included.
Results
We find that irritability forms a distinct dimension with substantial stability across time and that it is specifically associated with depression and anxiety in longitudinal studies. Evidence from genetic studies reveals that irritability is moderately heritable, and its overlap with depression is explained mainly by genetic factors. Behavioral and neuroimaging studies find that youth with persistent irritability show altered activations in amygdala, striatum, and frontal regions compared with age-matched healthy volunteers. Most knowledge about the treatment of irritability is based on effects of treatment on related conditions or through post hoc analyses of trial data.
Conclusion
We identify a number of research priorities including innovative experimental designs and priorities for treatment studies and conclude with recommendations for the assessment of irritability for researchers and clinicians.
Research and clinical interest in irritability have been on the rise in recent years. Yet several questions remain about the status of irritability in psychiatry, including whether irritability can be differentiated from other symptoms, whether it forms a distinct disorder, and whether it is a meaningful predictor of clinical outcomes. In this paper we try to answer these questions by reviewing the evidence on how reliably irritability can be measured and its validity.
Method
We combine a narrative and systematic review and meta-analysis of studies. For the systematic review and meta-analysis, we searched studies in Pubmed and Web of Science based on preselected criteria (i.e., irritability as a predictor of future psychiatric outcomes). One hundred sixty-three papers were reviewed, and 24 were included.
Results
We find that irritability forms a distinct dimension with substantial stability across time and that it is specifically associated with depression and anxiety in longitudinal studies. Evidence from genetic studies reveals that irritability is moderately heritable, and its overlap with depression is explained mainly by genetic factors. Behavioral and neuroimaging studies find that youth with persistent irritability show altered activations in amygdala, striatum, and frontal regions compared with age-matched healthy volunteers. Most knowledge about the treatment of irritability is based on effects of treatment on related conditions or through post hoc analyses of trial data.
Conclusion
We identify a number of research priorities including innovative experimental designs and priorities for treatment studies and conclude with recommendations for the assessment of irritability for researchers and clinicians.
| Original language | English |
|---|---|
| Pages (from-to) | 556–570 |
| Journal | Journal of the American Academy of Child and Adolescent Psychiatry |
| Volume | 55 |
| Issue number | 7 |
| Early online date | 6 May 2016 |
| DOIs | |
| Publication status | Published - Jul 2016 |