Comorbidity and Disability in Outpatients With Schizophrenia
To the Editor: Stefano Pallanti, M.D., and his collaborators (1) provided pioneering evidence that social anxiety disorder is associated with a lower health-related quality of life and higher lifetime rates of suicide attempts in outpatients with schizophrenia. However, given that 1) social anxiety disorder is strongly comorbid with major depressive disorder (2), 2) major depressive disorder has a greater impact on health-related quality of life than social anxiety disorder (3), and 3) major depressive disorder far outweighs social anxiety disorder as a risk factor for suicide (4), we feel that Dr. Pallanti and his collaborators might have considered the hypothesis that at least part of the correlations they found might have resulted from the effects of comorbid major depressive disorder rather than from those of social anxiety disorder.
Since Dr. Pallanti and his collaborators interviewed all of their patients with the Structured Clinical Interview for DSM-IV, it would be interesting if the authors could report the prevalence of mood disorders they identified in their sample and discuss the possibility that the presence of these disorders might have influenced their results.
1. Pallanti S, Quercioli L, Hollander E: Social anxiety in outpatients with schizophrenia: a relevant cause of disability. Am J Psychiatry 2004; 161:53–58Link, Google Scholar
2. Kessler RC, Stang P, Wittchen HU, Stein M, Walters EE: Lifetime co-morbidities between social phobia and mood disorders in the US National Comorbidity Survey. Psychol Med 1999; 29:555–567Crossref, Medline, Google Scholar
3. Schonfeld WH, Verboncoeur CJ, Fifer SK, Lipschutz RC, Lubeck DP, Buesching DP: The functioning and well-being of patients with unrecognized anxiety disorders and major depressive disorder. J Affect Disord 1997; 43:105–119Crossref, Medline, Google Scholar
4. Lonnqvist JK, Henriksson MM, Isometsa ET, Marttunen MJ, Heikkinen ME, Aro HM, Kuoppasalmi KI: Mental disorders and suicide prevention. Psychiatry Clin Neurosci 1995; 49(suppl 1):S111-S116Google Scholar