Treatment of difficult-to-treat depression - clinical guideline for selected interventions

Risk Phenotypes, Comorbidities, Pharmacotherapy, and Electroconvulsive Therapy (ECT) in a Cohort with Difficult-to-Treat Depression in Comparison to an Unmedicated Control Group

BACKGROUND

Approximately 15-25% of depressed patients suffer from difficult-to-treat depression (DTD). Patients with DTD require a thorough examination to avoid the oversight of treatable (psychiatric/somatic) comorbidities or (pseudo-)resistance to antidepressant drugs (ADs). Polymorphisms of the cytochrome P450 (CYP) enzymes 2D6 and 2C19, which play a major role in the metabolism of ADs, may contribute to resistance to ADs. Patients with DTD might benefit from electroconvulsive therapy (ECT).

METHODS

We enrolled 109 patients with DTD and 29 untreated depressed controls (UDC). We assessed risk phenotypes, comorbidities, and treatment, including ECT. We also performed pharmacokinetic analyses of CYP2D6 and CYP2C19.

RESULTS

DTD patients significantly more often suffered from comorbid psychiatric diseases, especially ICD-10: F40-F48 (DTD:40.4%, UDC:17.2%, OR 11.87, p=0.011) than UDC patients. DTD patients receiving ECT were more likely to achieve remission (37.7% vs. 11.8%, OR=3.96, p=0.023). Treatment with ADs did not differ between remitters and non-remitters. No significant differences were observed in the distribution of CYP2D6 and CYP2C19 variants between both groups.

CONCLUSION

Patients with DTD appear to experience comorbid neurotic stress and somatoform disorders (ICD-10: F40 - F48) more frequently. Therefore, a comprehensive differential diagnosis is crucial when patients do not respond sufficiently to antidepressant medication. Genotyping CYP2D6 and CYP2C19 should be considered.

Schema therapy versus treatment as usual for outpatients with difficult-to-treat depression: study protocol for a parallel group randomized clinical trial (DEPRE-ST)

BACKGROUND

About one third of patients with depression are in a condition that can be termed as "difficult-to-treat". Some evidence suggests that difficult-to-treat depression is associated with a higher frequency of childhood trauma and comorbid personality disorders or accentuated features. However, the condition is understudied, and the effects of psychotherapy for difficult-to-treat depression are currently uncertain. The aim of this trial is to investigate the beneficial and harmful effects of 30 sessions of individual schema therapy versus treatment as usual for difficult-to-treat depression in the Danish secondary, public mental health sector.

METHODS

In this randomized, multi-centre, parallel-group, superiority clinical trial, 129 outpatients with difficult-to-treat depression will be randomized (1:1) to 30 sessions of individual schema therapy or treatment as usual; in this context mainly group-based, short-term cognitive behaviour or psychodynamic therapy. The primary outcome is the change from baseline in depressive symptoms 12 months after randomization, measured on the observer-rated 6-item Hamilton Rating Scale for Depression. The secondary outcomes are health-related quality of life assessed with the European Quality of Life 5 Dimensions 5 Level Version, functional impairment assessed with the Work and Social Adjustment Scale, psychological wellbeing assessed with the WHO-5 Well-being Index, and negative effects of treatment assessed with the Negative Effects Questionnaire. Exploratory outcomes are improvement on patient self-defined outcomes, personal recovery, anxiety symptoms, anger reactions, metacognitive beliefs about anger, and perseverative negative thinking. Outcomes will be assessed at 6, 12, and 24 months after randomization; the 12-month time-point being the primary time-point of interest. Outcome assessors performing the depression-rating, data managers, statisticians, the data safety and monitoring committee, and conclusion makers for the outcome article will be blinded to treatment allocation and results. To assess cost-effectiveness of the intervention, a health economic analysis will be performed.

DISCUSSION

This trial will provide evidence on the beneficial and harmful effects, as well as the cost-effectiveness of schema therapy versus treatment as usual for outpatients with difficult-to-treat depression. The results can potentially improve treatment for a large and understudied patient group.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05833087. Registered on 15th April 2023 (approved without prompts for revision on 27th April 2023).

Effectiveness of pharmacogenomics on the response and remission of treatment-resistant depression: a meta-analysis of randomised controlled trials

Background

Pharmacogenomics (PGx) is a promising tool to realise tailored drug therapy for depression.

Aims

To investigate the treatment efficacy of PGx for treatment-resistant depression (TRD) compared with treatment as usual.

Methods

A systematic search was conducted in PubMed, Embase, the Cochrane Library, Web of Science and PsycINFO to identify relevant studies published from inception to 15 April 2023. Two-arm randomised controlled trials (RCTs) exploring the efficacy of PGx-guided versus unguided treatment for TRD were included. The risk of bias in the included studies was evaluated using the Cochrane risk of bias assessment tool. The overall quality of evidence was assessed using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach.

Results

Seven RCTs (n=3003) comparing PGx-guided (n=1492) and unguided (n=1511) groups were identified and analysed. PGx-guided treatment was superior to treatment as usual in response (relative risk (RR)=1.31; 95% confidence interval (95% CI): 1.15 to 1.49; p<0.001) and remission (RR=1.40; 95% CI: 1.09 to 1.80; p=0.009) improvements. Effect sizes for acceptability (RR=0.90; 95% CI: 0.80 to 1.02; p=0.100) and side effect burden (RR=0.58; 95% CI: 0.29 to 1.15; p=0.120) between the two groups were not statistically different. The overall quality of evidence was rated from 'very low' (25%) to 'low' (75%) based on the GRADE criteria.

Conclusions

PGx-guided treatment has shown a small overall effect in improving the response and remission rates for patients with TRD. However, these results should be interpreted cautiously because of the few included studies and the low quality of evidence. Further high-quality clinical trials are warranted to confirm the findings.

PROSPERO registration number

CRD42022340182.

Plasma Brain-Derived Neurotrophic Factor Levels in First-Episode and Recurrent Major Depression and before and after Bright Light Therapy in Treatment-Resistant Depression

Brain-derived neurotrophic factor (BDNF) is implicated in the etiology and treatment response in major depressive disorder (MDD). However, peripheral BDNF concentrations have not been compared across different MDD stages. Bright light therapy (BLT) offers some potential in treatment-resistant depression (TRD), but its effects on BDNF levels are unknown. This study included a cross-sectional analysis of plasma BDNF concentration in females with TRD, unmedicated MDD patients, and healthy controls (HC), and measurements of longitudinal BLT effects on plasma BDNF levels in TRD patients. The present study included 55 drug-naïve, first-episode patients, 25 drug-free recurrent-episode MDD patients, 71 HC participants, and 54 TRD patients. Patients were rated by Hamilton Depression Rating Scale (HAMD)-17 and the Montgomery-Åsberg Depression Rating Scale (MADRS). Patients with TRD received BLT during 4 weeks. The total HAMD-17 and MADRS scores decreased following BLT. All patient groups had lower plasma BDNF than HC, but BDNF levels did not differ between first- and recurrent-episode BDNF patients and TRD patients before or after BLT. However, responders and remitters to BLT had higher post-treatment plasma BDNF concentrations than patients who did not achieve response or remission. The changes in plasma BDNF levels may be candidates for biomarkers of treatment response to BLT in TRD patients.

Illuminating the way: the role of bright light therapy in the treatment of depression

INTRODUCTION

Despite the growing number of different therapeutic options, treatment of depression is still a challenge. A broader perspective reveals the benefits of bright light therapy (BLT). It stimulates intrinsically photosensitive retinal ganglion cells, which induces a complex cascade of events, including alterations in melatonergic, neurotrophic, GABAergic, glutamatergic, noradrenergic, serotonergic systems, and HPA axis, suggesting that BLT effects expand beyond the circadian pacemaker.

AREAS COVERED

In this review, the authors present and discuss recent data of BLT in major depressive disorder, non-seasonal depression, bipolar depression or depressive phase of bipolar disorder, and seasonal affective disorder, as well as in treatment-resistant depression (TRD). The authors further highlight BLT effects in various depressive disorders compared to placebo and report data from several studies suggesting a response to BLT in TRD. Also, the authors report data showing that BLT can be used both as a monotherapy or in combination with other pharmacological treatments.

EXPERT OPINION

BLT is an easy-to-use and low-budget therapy with good tolerability. Future studies should focus on clinical and biological predictors of response to BLT, on defining specific populations which may benefit from BLT and establishing treatment protocols regarding timing, frequency, and duration of BLT.