ESPECTRA: searching the bipolar spectrum in eating disorder patients

Mood spectrum comorbidity in patients with anorexia and bulimia nervosa

PURPOSE

To investigate the presence of mood spectrum signs and symptoms in patients with anorexia nervosa, restricting subtype (AN-R) or bulimia nervosa (BN).

METHOD

55 consecutive female patients meeting DSM-IV criteria for eating disorders (EDs) not satisfying DSM-IV criteria for Axis I mood disorders were evaluated with the Lifetime Mood Spectrum Self-Report (MOODS-SR) and the Mini-International Neuropsychiatric Interview (MINI). The MOODS-SR explored the subthreshold comorbidity for mood spectrum symptoms in patients not reaching the threshold for a mood disorder Axis I diagnosis. MOODS-SR included 161 items. Separate factor analyses of MOODS-SR identified 6 'depressive factors' and 9 'manic-hypomanic factors'.

RESULTS

The mean total score of MOODS-SR was significantly higher in BN than in AN-R patients (97.5 ± 25.4 vs 61.1 ± 38.5, respectively; p = 0.0001). 63.6 % of the sample (n = 35) endorsed the threshold of ≥61 items, with a statistically significant difference between AN-R and BN (39.3 % vs 88.9 %; χ ² = 14.6; df = 1; p = 0.0001). Patients with BN scored significantly higher than AN-R patients on several MOODS-SR factors: (a) MOODS-SR depressive component: 'depressive mood' (11.2 ± 7.4 vs 16.0 ± 5.8; p < 0.05), 'psychomotor retardation' (5.4 ± 5.6 vs 8.9 ± 3.8; p = 0.003), 'psychotic features' (2.0 ± 1.8 vs 4.1 ± 1.6; p = 0.001), 'neurovegetative symptoms' (5.0 ± 2.6 vs 7.7 ± 1.7; p = 0.001); (b) MOODS-SR manic/hypomanic component: 'psychomotor activation' (4.3 ± 3.6 vs 7.4 ± 3.1; p = 0.002), 'mixed instability' (1.0 ± 1.5 vs 2.0 ± 1.6; p < 0.05), 'mixed irritability' (2.5 ± 1.8 vs 3.7 ± 1.6; p < 0.05), 'inflated self-esteem' (1.1 ± 1.4 vs 2.1 ± 1.6; p < 0.05), and 'wastefulness/recklessness' (1.0 ± 1.4 vs 2.0 ± 1.2; p = 0.009).

CONCLUSIONS

MOODS-SR identifies subthreshold mood signs/symptoms among patients with AN-R, and BN and with no Axis I comorbidity for mood disorders, and provides a better definition of clinical phenotypes.

Occurrence of bipolar spectrum disorder and comorbidities in women with eating disorders

Background

Eating disorder (ED) patients often have comorbidities with other psychiatric disorders, especially with mood disorders. Although recent studies suggest an intimate relationship between ED and bipolar disorder (BD), the study on a broader bipolar spectrum definition has not been done in this population. We aimed to study the occurrence of bipolar spectrum (BS) and comorbidities in eating disorder patients of a tertiary service provider.

Methods

Sixty-nine female patients diagnosed with anorexia nervosa, bulimia nervosa, or eating disorder not otherwise specified were evaluated. The assessment comprised the Structured Clinical Interview for DSM-IV Axis I Disorders (SCID-I), clinical criteria for diagnosis of the Zurich bipolar spectrum. Mann–Whitney tests compared means of continuous variables. The association between categorical variables and the groups was described using contingency tables and analyzed using the chi-square or Fisher's exact test. The level of significance alpha was set at 5%.

Results

The results showed that 68.1% of patients had comorbidity with bipolar spectrum, and this was associated with higher family income, proportion of married people, and comorbidity with substance use. The ED with BS group showed higher rates of substance use comorbidity (40.4%) than the ED without BS group (13.6%).

Discussion

These results showed that the bipolar spectrum is a common comorbidity in patients with eating disorders and is associated with correlates of clinical importance, notably the comorbidity with substance use. Due to the pattern of similarity between the groups with and without comorbid bipolar spectrum in relation to various outcomes evaluated, the identification of comorbidity can be difficult. However, the precise diagnosis and careful identification of clinical correlates may contribute to future advances in treating these conditions. Further studies are necessary to evaluate the association of other clinical correlates and its possible causal association.