Bipolar depression had more atypical depressive symptoms in comparison with unipolar depression

Background

Depressive patients with atypical symptoms tend to cause greater functional impairment. This study examined the differences of the atypical depressive symptoms between unipolar and bipolar depressive patients (BP I and BP II).

Methods

We studied 466 depressed patients (262 unipolar and 204 bipolar subjects, in which 122 BP I depression, 82 BP II depression) diagnosed with DSM-IV criteria. Atypical depressive symptoms were also evaluated with DSM-IV criteria for atypical features specifier. Binary logistic regression was used to examine the associations of atypical depressive symptoms with depressive disorders after control of confounding variables.

Results

The prevalence with any atypical depressive symptoms in unipolar depressive disorder was 32.8 % (86/262), and in bipolar depression was 44.6 % (91/204), X² = 6.76, P = 0.009. In stepwise binary logistic regression analysis, patients with bipolar depression had more females, more positive psychiatric history, more weight gain or increase in appetite, more interpersonal rejection sensitivity, and more visual values of severest pain.

Limitations

The participants recruited were both inpatients and outpatients in one major hospital which might influence the generality of the study. The cross-sectional research methods can't work out causality.

Conclusions

Bipolar depression and major depressive disorder exhibit subtle differences in presentation, which may help guide the early intervention, initial diagnosis and the choice of therapy.