Long-Term Outcome of Major Depressive Disorder in Psychiatric Patients Is Variable

K. Mikael Holma, M.D.; Irina A. K. Holma, M.D.; Tarja K. Melartin, M.D., Ph.D.; Heikki J. Rytsälä, M.D., Ph.D.; and Erkki T. Isometsä, M.D., Ph.D.

Objective: The prevailing view of outcome of major depressive disorder (MDD), based on mostly inpatient cohorts sampled from tertiary centers, emphasizes chronicity and frequent recurrences. We investigated the long-term outcome of a regionally representative psychiatric MDD cohort comprising mainly outpatients.

Method: The Vantaa Depression Study included 163 patients with DSM-IV MDD (71.5% of those eligible) diagnosed using structured and semistructured interviews and followed up at 6 months, 18 months, and 5 years with a life chart between February 1, 1997, and April 30, 2004. The effects of comorbid disorders and other predictors on outcome were comprehensively investigated.

Results: Over the 5-year follow-up, 98.8% of patients achieved a symptom state below major depressive episode (MDE) criteria, and 88.4% reached full remission, with the median time to full remission being 11.0 months. Nearly one third (29.3%) had no recurrences, whereas 30.0% experienced 1, 12.9% experienced 2, and 27.9% experienced 3 or more recurrences. Preceding dysthymic disorder (p = .028), cluster C personality disorder (p = .041), and longer MDE duration prior to entry (p = .011) were the most significant predictors of longer time in achieving full remission. Severity of MDD and comorbidity, especially social phobia, predicted probability of, shorter time to, and number of recurrences.

Conclusion: Previous literature on mostly inpatient MDD may have, by generalizing from patients with the most severe psychopathology, overemphasized chronicity of MDD. The long-term outcome of MDD in psychiatric care is variable, with about one tenth of patients having poor, one third having intermediate, and one half having favorable outcomes. In addition to known predictors, cluster C personality disorders and social phobia warrant further attention as predictors of MDD outcome among outpatients.

(J Clin Psychiatry 2008;69:196-205; online ahead of print January 30, 2008)

Received Nov. 20, 2006; accepted June 11, 2007. From the Department of Mental Health and Alcohol Research, National Public Health Institute, Helsinki (all authors); the Department of Psychiatry, Helsinki University Central Hospital (HUCH), Helsinki (Drs. K. Holma, I. Holma, and Isometsä); and HUCH, Peijas Hospital, Healthcare District of Helsinki and Uusimaa, Vantaa (Drs. Melartin and Rytsälä), Finland.

This study was supported by grants from the Academy of Finland, the Healthcare District of Helsinki and Uusimaa, and the Medical Society of Finland.

The authors report no additional financial or other relationships relevant to the subject of this article.

Corresponding author and reprints: Erkki T. Isometsä, M.D., Ph.D., Institute of Clinical Medicine, Department of Psychiatry, Välskärinkatu 12 A, P.O. Box 22, 00014, University of Helsinki, Finland (e-mail: erkki.isometsa@hus.fi).