Longitudinal syndromal and sub-syndromal symptoms after severe depression: 10-year follow-up study.
BACKGROUND
Few follow-up studies of depression have evaluated depressive symptomatology over time at both threshold and sub-threshold levels.


OBJECTIVE
To evaluate long-term longitudinal symptomatic course after an episode of severe depression.


METHODS
A total of 61 participants from a previous study cohort underwent a detailed interview covering the longitudinal course of depression and pharmacological treatment over 8-11 years of follow-up.


RESULTS
Of the follow-up months, 52% were spent at an asymptomatic level, 15% at minor symptom level, 20% at residual symptom level and 13% at full depression level. Also, 30% of follow-up months were spent in an episode of depression, and 18% of patients never achieved asymptomatic status during follow-up. The percentage of patients at each symptom level remained relatively stable after the first 2 years, but levels in individuals fluctuated, with a mean of two changes in symptom levels per follow-up year.


CONCLUSIONS
After severe episodes, sub-syndromal levels of depression are common and persistent, with considerable fluctuation suggesting a continuum between sub-syndromal subtypes and full depression.
Kennedy
Noel
N
Institute of Psychiatry, London, UK. N.Kennedy@iop.kcl.ac.uk
Abbott
Rosemary
R
Paykel
Eugene S
ES
D000328:Adult; D000928:Antidepressive Agents / Q000008:administration & dosage; D002908:Chronic Disease; D003866:Depressive Disorder / Q000175:diagnosis* / Q000188:drug therapy / Q000523:psychology; D004334:Drug Administration Schedule; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007406:Interview, Psychological; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D011569:Psychiatric Status Rating Scales
D000928:Antidepressive Agents