Comorbidity of bipolar and eating disorders: distinct or related disorders with shared dysregulations?
BACKGROUND
The co-occurrence of bipolar and eating disorders, though of major clinical and public health importance, remains relatively unexamined.


METHODS
In reviewing the literature on this comorbidity, we compared bulimia, anorexia nervosa, bulimia nervosa, binge eating disorders and bipolar disorders on phenomenology, course, family history, biology, and treatment response.


RESULTS
Epidemiological studies show an association between subthreshold bipolar disorder and eating disorders in adolescents, and between hypomania and eating disorders, especially binge eating behavior, in adults. Of the clinical studies, most show that patients with bipolar disorder have elevated rates of eating disorders, and vice versa. Finally, the phenomenology, course, comorbidity, family history, and pharmacologic treatment response of these disorders show considerable overlap on all of these parameters. In particular, on phenomenologic grounds--eating dysregulation, mood dysregulation, impulsivity and compulsivity, craving for activity and/or exercise--we find many parallels between bipolar and eating disorders. Overall, the similarities between these disorders were more apparent when examined in their spectrum rather than full-blown expressions.


CONCLUSIONS
Despite an extensive literature on each of these disorders, studies examining their overlap across all these parameters are relatively sparse and insufficiently systematic.


CONCLUSIONS
Nonetheless, the reviewed literature leaves little doubt that bipolar and eating disorders--particularly bulimia nervosa and bipolar II disorder--are related. Although several antidepressants and mood stabilizers have shown promise for eating disorders, their clinical use when these disorders co-exist with bipolarity is still very much of an art. We trust that this review will stimulate more rigorous research in their shared putative underlying psychobiologic mechanisms which, in turn, could lead to more rational targeted treatments.
McElroy
Susan L
SL
Psychopharmacology Research Program, University of Cincinnati College of Medicine, P.O. Box 670559, 231 Bethesda Avenue, Cincinnati, OH 45267-0559, USA. susan.mcelroy@uc.edu
Kotwal
Renu
R
Keck
Paul E
PE
Akiskal
Hagop S
HS
D000293:Adolescent; D000328:Adult; D000856:Anorexia Nervosa / Q000175:diagnosis / Q000453:epidemiology* / Q000628:therapy; D000927:Anticonvulsants / Q000627:therapeutic use; D000928:Antidepressive Agents / Q000627:therapeutic use; D001714:Bipolar Disorder / Q000175:diagnosis / Q000453:epidemiology* / Q000628:therapy; D001835:Body Weight / Q000502:physiology; D002032:Bulimia / Q000175:diagnosis / Q000453:epidemiology* / Q000628:therapy; D015897:Comorbidity; D005247:Feeding Behavior / Q000523:psychology; D005260:Female; D006801:Humans; D008094:Lithium / Q000627:therapeutic use; D008297:Male; D011569:Psychiatric Status Rating Scales; D011613:Psychotherapy
D000927:Anticonvulsants; D000928:Antidepressive Agents; D008094:Lithium