Hypomania-Checklist-33: risk stratification and factor structure in a mixed psychiatric adolescent sample.

Background: The 33-item Hypomania Checklist (HCL-33) has been shown to distinguish between adolescent bipolar disorder (BD) and unipolar depression. To investigate the utility of the HCL-33 as a screening tool in routine diagnostics, the frequency and psychopathological characteristics of detected individuals in a mixed psychiatric sample necessitate more examination.

Methods: The HCL-33, Children's Depression Inventory, Beck's Anxiety Inventory, and Strengths and Difficulties Questionnaire were completed by 285 children and adolescents (12-18 years) in a mixed psychiatric sample. Applying the proposed HCL-33 cut-off score of ≥ 18, individuals with depressive symptoms were divided into at-risk or not at-risk for BD groups. The factorial structure, sum and factor score correlations with psychopathology, and impact on daily functioning were assessed.

Results: 20.6% of the sample met at-risk criteria for BD. These individuals (n = 55) were older, more anxious, and showed more conduct problems vs the not at-risk group (n = 107). A two- and a three-factor model were pursued with the same Factor 1 ("active-elated"). Factor 2 ("risk-taking/irritable") was separated into 2a ("irritable-erratic") and 2b ("outgoing-disinhibited") in the three-factor model. Whereas higher Factor 2 and 2a scores correlated with a broad range of more severe symptomatology (i.e., depression, anxiety, hyperactivity), higher Factor 1 and 2b scores correlated with more emotional and conduct problems, respectively. 51.7% of the sample reported a negative impact from hypomanic symptoms on daily functioning.

Limitations: Cross-sectional design and data collection in a single mental health service.

Conclusions: The HCL-33 may be a useful tool to improve diagnostics, especially in adolescents with depressive symptoms additionally presenting with anxious symptoms and conduct problems.