Clinical correlates of atypical depression and validation of the French version of the Scale for Atypical Symptoms (SAS)

J Affect Disord. 2009 Nov;118(1-3):113-7. doi: 10.1016/j.jad.2009.02.005. Epub 2009 Mar 9.

Abstract

Background: The 8-item "Scale for Atypical Symptoms" (SAS) and its structured interview, the SIGH-SAD, have been developed to assess atypical symptoms of depression in winter depression. Although they are commonly used, no validation study has yet been conducted.

Methods: 270 consecutive depressed inpatients were assessed prospectively. Pearson's correlation coefficients between fulfilment of Liebowitz criteria for atypical depression and both the SAS score and the atypical balance [ratio of the AS score to the total score on the Hamilton Depression Rating Scale 29-item (HDRS-29)] were calculated. The SAS was evaluated against Liebowitz criteria using binary logistic regression. A ROC curve was performed with the atypical balance against the fulfilment of Liebowitz criteria.

Results: 18.5% of patients met the criteria for atypical depression. The presence of an atypical depression was significantly correlated with both the atypical score (r=0.42) and the atypical balance (r=0.51). The logistic regression showed that a higher score on the SAS, the absence of a somatic syndrome (ICD-10) and a lower HDRS-21 score were independent predictors of an atypical depression while age, gender and bipolarity were not. The ROC curve showed that an atypical balance of 29% was the optimal threshold for the diagnosis of atypical depression (sensitivity=0.86, specificity=0.79).

Limitation: Patients with bipolar I and II were not distinguished.

Conclusion: Atypical depression is relatively frequent in hospitalised patients. The concurrent validity of the French version of the SAS and its structured interview, the SIGH-SAD is satisfactory.

MeSH terms

  • Adult
  • Affective Disorders, Psychotic / classification
  • Affective Disorders, Psychotic / diagnosis
  • Affective Disorders, Psychotic / psychology
  • Aged
  • Bipolar Disorder / classification
  • Bipolar Disorder / diagnosis
  • Bipolar Disorder / psychology
  • Cross-Cultural Comparison*
  • Depressive Disorder / classification
  • Depressive Disorder / diagnosis*
  • Depressive Disorder / psychology
  • Diagnosis, Differential
  • Female
  • France
  • Humans
  • Language*
  • Male
  • Middle Aged
  • Personality Inventory / statistics & numerical data*
  • Prospective Studies
  • Psychometrics / statistics & numerical data
  • Reproducibility of Results
  • Seasonal Affective Disorder / classification
  • Seasonal Affective Disorder / diagnosis*
  • Seasonal Affective Disorder / psychology
  • Somatoform Disorders / classification
  • Somatoform Disorders / diagnosis
  • Somatoform Disorders / psychology
  • Translating