title: Chronotype and body composition in bipolar disorder.
abstract: We explored whether obesity in patients with bipolar disorder is associated with their chronotype. A group of 29 patients with bipolar I disorder, not currently experiencing an affective episode, were assessed for total body fat, mood symptoms, and self-reported circadian chronotype and sleep quality. Chronotype explained 19% of the variance in body fat, after age, sex, mood state, and sleep quality were accounted for. This association suggested that evening chronotype patients have a higher percentage of total body fat. Evening chronotype could be a proxy for as yet unknown specific causes of the high rate of obesity and obesity-related diseases in bipolar disorder.
authors.affiliation: Department of Psychiatry, University of Pittsburgh School of Medicine, Pennsylvania, USA. sorecai@upmc.edu
authors.forename: Isabella
authors.initials: I
authors.lastname: Soreca
authors.forename: Andrea
authors.initials: A
authors.lastname: Fagiolini
authors.forename: Ellen
authors.initials: E
authors.lastname: Frank
authors.forename: Bret H
authors.initials: BH
authors.lastname: Goodpaster
authors.forename: David J
authors.initials: DJ
authors.lastname: Kupfer
mesh_terms: D000328:Adult; D000339:Affect / Q000502:physiology*; D001714:Bipolar Disorder / Q000503:physiopathology* / Q000523:psychology*; D001823:Body Composition; D002940:Circadian Rhythm; D003863:Depression / Q000503:physiopathology / Q000523:psychology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000503:physiopathology*; D018579:Patient Selection; D012890:Sleep / Q000502:physiology*