Previous research of bipolar disorder (BD) shows a high rate of comorbidities with other psychiatric disorders, including eating disorders (EDs), Valentin Flaudias, PhD, of Nantes (France) University and colleagues wrote.
Valentin Flaudias
Dr. Valentin Flaudias
“There is growing evidence that, compared with individuals with BD alone, individuals with both BD and EDs have a more severe clinical profile, including increased mood instability, alcohol use disorders, anxiety disorders, more depressive episodes, more rapid cycling, increased suicidality, and poorer response to medication,” but studies of BD type-specific ED prevalence have been inconsistent, they said.
In a study published in the Journal of Affective Disorders, the researchers reviewed data from 2,929 outpatients who underwent assessments for BD at 1 of 12 psychiatric centers in France. Of these, 1,505 met criteria for type I and 1,424 met criteria for type II. The post hoc analysis included identification of lifetime prevalence of ED. Diagnosis was based on the DSM-4-TR and the researchers considered three ED types: anorexia nervosa (AN), bulimia nervosa (BN), and binge-eating disorder (BED). Subtypes of BD were type I and type II. DSM not otherwise specified diagnoses for BD and EDs were excluded. The mean age of the participants was 40.5 years, and 61% were women.
A total of 479 individuals met criteria for comorbid EDs (16.4%). ED prevalence was significantly higher in BD type II patients than in BD type I patients (20.6 % vs. 12.4 %, P < .001). The overall breakdown according to ED subtype was 30% for AN, 13% for BN, and 56% for BED. The researchers found no significant differences in patients with AN, BN, or BED according to BD subtype.
In a multivariate analysis, BD patients with ED were more likely than those without ED to be women (77% vs. 55%), especially those with AN (95% vs. 82%).
BD patients with ED also tended to be younger than those without ED (37 years vs. 41 years) and reported more frequent suicide attempts (50% vs. 35%). Younger age and more frequent suicide attempts were further significant among BD patients with AN, compared with those with BED, but BD patients with BED reported higher levels of childhood trauma.
BD patients with ED also reported higher levels of depressive symptoms than those without ED, although history of psychosis was less frequent among BD patients with AN and BED compared with BD patients without EDs.
Overall, “after controlling for other variables, the independent factors differentiating BD patients with versus without ED were primarily younger age, female gender, abnormal BMI, increased affective lability and higher comorbidity with anxiety disorders,” the researchers wrote. In addition, presence of EDs except for AN was associated with decreased current functioning.
The findings were limited by several factors including the cross-sectional design, lack of a control group of non-BD individuals, and the consideration of ED over a lifetime, and small number of BN cases, the researchers noted.
However, the results suggest a high prevalence of ED in BD patients and highlight the need to screen BD patients for ED and provide integrated care. More research is needed to explore the evolution of the two conditions as comorbidities and to examine subtypes and of both conditions and their interactions, they concluded.
The study was supported by the FondaMental Foundation, French National Institute for Health and Medical Research, Public Hospitals of Paris, and the French National Research Agency’s Investment for the Future program. The researchers had no financial conflicts to disclose.