BackgroundSystematic studies on the outcome of treatment-resistant depression are
scarce.AimsTo describe the longer-term outcome and predictors of outcome in
treatment-resistant depression.MethodOut of 150 patients approached, 118 participants with confirmed
treatment-resistant depression (unipolar, n= 7; bipolar,
n=27; secondary, n=14) treated in a
specialist in-patient centre were followed-up for between 8 and 84 months
(mean=39, s.d.=22).ResultsThe majority of participants attained full remission (60.2%), most of
whom (48.3% of total sample) showed sustained recovery (full remission
for at least 6 months). A substantial minority had persistent
subsyndromal depression (19.5%) or persistent depressive episode (20.3%).
Diagnosis of bipolar treatment-resistant depression and poorer social
support were associated with early relapse, whereas strong social
support, higher educational status and milder level of treatment
resistance measured with the Maudsley Staging Method were associated with
achieving quicker remission. Exploratory analysis of treatment found
positive associations between treatment with a monoamine oxidase
inhibitor (MAOl) in unipolar treatment-resistant depression and attaining
remission at discharge and at final follow-up, and duloxetine use
predicted attainment of remission at final follow-up.ConclusionsAlthough many patients with treatment-resistant depression experience
persistent symptomatology even after intensive, specialist treatment,
most can achieve remission. The choice of treatment and presence of good
social support may affect remission rates, whereas those with low social
support and a bipolar diathesis should be considered at higher risk of
early relapse. We suggest that future work to improve the long-term
outcome in this disabling form of depression might focus on social
interventions to improve support, and the role of neglected
pharmacological interventions such as MAOIs.