Comparative effectiveness of esketamine in the treatment of anhedonia in bipolar and unipolar depression

BACKGROUND

Anhedonia is a symptom associated with poorer outcomes in depression treatment, including resistance to treatment, higher functional impact and suicidality. Few drugs are known to adequately treat anhedonia in both unipolar and bipolar depression. The NMDA antagonist ketamine has been demonstrated to be effective in rapidly ameliorating anhedonia in depressive episodes. The main aim of present study is to evaluate the anti-anhedonic effect of esketamine, the S-enantiomer of ketamine recently approved for treatment-resistant depression, in unipolar and bipolar depression.

METHODS

70 patients with unipolar or bipolar depression were treated with 6 weekly subcutaneous esketamine infusions (0.5-1mg/kg). Anhedonia was measured through MADRS item 8 before and 24h after each infusion.

RESULTS

A significant reduction in anhedonia severity was observed (p<0.0001) after 6 infusions. The effect was statistically significant 24h after the first infusion (p<0.001) in both unipolar and bipolar groups and increased with repeated infusions. Anti-anhedonic effect of esketamine did not differ between groups.

LIMITATIONS

This is an open-label, real-world study. Lack of blinding and of a placebo arm may limit the interpretation of findings.

CONCLUSION

Although preliminary, present findings suggest that repeated subcutaneous esketamine infusions are effective for the treatment of anhedonia in both unipolar and bipolar depressed patients. These results need to be confirmed through replication in larger double-blinded controlled trials.

Activity/rest rhythm of depressed adolescents undergoing therapy: case studies

INTRODUCTION:

Disorders of circadian rhythms have been reported in studies of both depressed children and of depressed adolescents. The aim of this study was to evaluate whether there is a relationship between the 24-hour spectral power (24h SP) of the activity/rest rhythm and the clinical course of depression in adolescents.

METHODS:

Six 14 to 17-year-old adolescents were recruited for the study. They were all suffering from major depressive disorder, according to the Diagnostic and Statistical Manual of Mental Disorders, 4th edition (DSM-IV) criteria, as identified by the Schedule for Affective Disorders and Schizophrenia for School Aged Children: Present and Lifetime Version (K-SADS-PL). Depressive symptoms were assessed using the Children's Depression Rating Scale - Revised (CDRS-R) and clinical evaluations. Locomotor activity was monitored over a period of 13 consecutive weeks. Activity was measured for 10-minute periods using wrist-worn activity monitors. All patients were prescribed sertraline from after the first week up until the end of the study.

RESULTS:

We found a relationship between high CDRS values and low 24-hour spectral power.

CONCLUSIONS:

The 24h SP of the activity/rest rhythm correlated significantly (negatively) with the clinical ratings of depression.