Crossed clinical features between eating disorders and types of bipolar disorder: Results from the FondaMental Advanced Centers of Expertise- Bipolar Disorder cohort

Background: Eating disorders (EDs) are liable to alter the disease course of bipolar disorder (BD). We explored the crossed clinical features between EDs and BD, particularly as a function of BD type (BD1 vs. BD2). Methods: 2929 outpatients attending FondaMental Advanced Centers of Expertise were assessed for BD and lifetime EDs with a semi-structured interview, and their sociodemographic, dimensional and clinical data were collected according to a standardized procedure. For each ED type, bivariate analyses were used to investigate associations between these variables and the type of BD type followed by multinomial regressions with the variables associated with EDs and BDs after Bonferroni correction. Results: Comorbid EDs were diagnosed in 478 (16.4 %) cases, and were more prevalent in patients with BD2 than in those with BD1 (20.6 % vs. 12.4 %, p < 0.001). Regression models showed no difference according to the subtype of bipolar disorder on the characteristics of patients with anorexia nervosa (AN), bulimia nervosa (BN) or binge eating disorder (BED). After multiple adjustments, the factors differentiating BD patients with versus without ED were primarily age, gender, body mass index, more affective lability and comorbidity with anxiety disorders. BD patients with BED also scored higher regarding childhood trauma. BD patients with AN also showed higher risk of past suicide attempts than those with BED. Conclusions: In a large sample of patients with BD, we found a high prevalence of lifetime EDs, especially for the BD2 type. EDs were associated with several severity indicators, but not with BD type-specific characteristics. This should prompt clinicians to carefully screen patients with BD for EDs, regardless of BD and ED types.

Automated summary

This study investigated the relationship between eating disorders (EDs) and bipolar disorder (BD) types. The results showed that BD2 patients had a higher prevalence of EDs compared to BD1 patients. Factors such as age, gender, body mass index, affective lability, and comorbidity with anxiety disorders were associated with EDs in BD patients. There were no significant differences in EDs between different BD types.