Methods | Statistics | Clinical | Educational | Industrial | Professional items | World psychology |
- Main article: Clinical depression
Once an episode of depression occurs, there is at least a 50% chance of recurrence during an individual's lifetime. Odds of recurrence increase up to 90% in individuals who have had several bouts of depression. Up to one-third of depressive episodes can become chronic
The effectiveness of treatment often depends on factors such as the amount of optimism and hope the sufferer is able to maintain, the control s/he has over stressors, the severity of symptoms, the amount of time the sufferer has been depressed, the results of previous treatments, and the degree of support of family, friends, and significant others.
Although treatment is generally effective, in some cases the condition does not respond. Treatment-resistant depression warrants a full assessment, which may lead to the addition of psychotherapy, higher medication dosages, changes of medication or combination therapy, a trial of ECT/electroshock, or even a change in the diagnosis, with subsequent treatment changes. Although this process helps many, some people's symptoms continue unabated.
Relapse is more likely if treatment has not resulted in full remission of symptoms.4 In fact, current guidelines for antidepressant use recommend 4 to 6 months of continuing treatment after symptom resolution to prevent relapse.
Combined evidence from many randomized controlled trials indicates that continuing antidepressant medications after recovery substantially reduces (halves) the chances of relapse. This preventive effect probably lasts for at least the first 36 months of use.
Anecdotal evidence suggests that chronic disease is accompanied by relapses after prolonged treatment with antidepressants (Tachyphylaxis). Psychiatric texts suggest that physicians respond to relapses by increasing dosage, complementing the medication with a different class, or changing the medication class entirely. The reason for relapse in these cases is as poorly understood as the change in brain physiology induced by the medications themselves. Possible reasons may include aging of the brain or worsening of the condition. Most SSRI psychiatric medications were developed for short-term use (a year or less) but are widely prescribed for indefinite periods. \
- ↑ Geddes, JR, Carney SM, Davies C, Furukawa TA, Kupfer DJ, Frank E, Goodwin GM (22 February 2003). Relapse prevention with antidepressant drug treatment in depressive disorders: a systematic review. Lancet 361 (9358): 653�61. PMID 12606176.