Bipolar spectrum disorder in severely obese patients seeking surgical treatment

Background: Much of the literature investigating the link between mood disorders and obesity has focused on depression whereas historic polarity of mood has not been previously carefully assessed. The aim of the present study has been to evaluate the prevalence of the entire bipolar spectrum, by including subsyndromal hypomania, and its related demographic and clinical correlates, in severely obese patients seeking surgical treatment. Methods: Eighty-three consecutive bariatric patients who presented for presurgical psychiatric consultation were systematically interviewed with both the SCID-CV questionnaire and, as a self-assessment instrument, with the Hypomania Symptom Checklist (HCL-32) on all past hypomanic behaviours (focusing more on prior overactivity than on mood changes) regardless of duration and initial negative response to the screening question on mood. Results: A bipolar spectrum disorder was found in 89% of severely obese patients, with the highest prevalence rates for bipolar II disorder. Comorbidity with panic disorder was observed in 30% of bipolar spectrum patients. Limitations: The lack of normal-weight or general medical control groups and the reliance on self-report, retrospective assessment for the collection of some parameters warrant some caution in the interpretation of substantive findings. Conclusions: These findings suggest that bipolar spectrum illness, in particular a hypomanic condition characterized by overactivity, is very common in severely obese subjects, thus contradicting previous evidence of low levels of physical activity in this population. Given the high prevalence rates of bipolar spectrum in morbid obesity, this study encourages further research on the causal association