Recruitment Challenges for Studies of Deep Brain Stimulation for Treatment-Resistant Depression

Why are clinical trials of deep brain stimulation terminated? An analysis of clinicaltrials.gov

Background

Although deep brain stimulation (DBS) has established uses for patients with movement disorders and epilepsy, it is under consideration for a wide range of neurologic and neuropsychiatric conditions.

Objective

To review successful and unsuccessful DBS clinical trials and identify factors associated with early trial termination.

Methods

The ClinicalTrials.gov database was screened for all studies related to DBS. Information regarding condition of interest, study aim, trial design, trial success, and, if applicable, reason for failure was collected. Trials were compared and logistic regression was utilized to identify independent factors associated with trial termination.

Results

Of 325 identified trials, 79.7% were successful and 20.3% unsuccessful. Patient recruitment, sponsor decision, and device issues were the most cited reasons for termination. 242 trials (74.5%) were interventional with 78.1% successful. There was a statistically significant difference between successful and unsuccessful trials in number of funding sources (p = 0.0375). NIH funding was associated with successful trials while utilization of other funding sources (academic institutions and community organizations) was associated with unsuccessful trials. 83 trials (25.5%) were observational with 84.0% successful; there were no statistically significant differences between successful and unsuccessful observational trials.

Conclusion

One in five clinical trials for DBS were found to be unsuccessful, most commonly due to patient recruitment difficulties. The source of funding was the only factor associated with trial success. As DBS research continues to grow, understanding the current state of clinical trials will help design successful future studies, thereby minimizing futile expenditures of time, cost, and patient engagement.

Outcome differences between males and females undergoing deep brain stimulation for treatment-resistant depression: systematic review and individual patient data meta-analysis

BACKGROUND

Treatment-resistant depression (TRD) occurs more commonly in women. Deep brain stimulation (DBS) is an emerging treatment for TRD, and its efficacy continues to be explored. However, differences in treatment outcomes between males and females have yet to be explored in formal analysis.

METHODS

A PRISMA-compliant systematic review of DBS for TRD studies was conducted. Patient-level data were independently extracted by two authors. Treatment response was defined as a 50 % or greater reduction in depression score. Percent change in depression scores by gender were evaluated using random-effects analyses.

RESULTS

Of 737 records, 19 studies (129 patients) met inclusion criteria. The mean reduction in depression score for females was 57.7 % (95 % CI, 64.33 %-51.13 %), whereas for males it was 35.2 % (95 % CI, 45.12 %-25.23 %) (p < 0.0001). Females were more likely to respond to DBS for TRD when compared to males (OR = 2.44, 95 % CI 1.06, 1.95). These differences varied in significance when stratified by DBS anatomical target, age, and timeframe for responder classification.

LIMITATIONS

Studies included were open-label trials with small sample sizes.

CONCLUSIONS

Our findings suggest that females with TRD respond at higher rates to DBS treatment than males. Further research is needed to elucidate the implications of these results, which may include connectomic sexual dimorphism, depression phenotype variations, or unrecognized symptom reporting differences. Methodological standardization of outcome scales, granular demographic data, and individual subject outcomes would allow for more robust comparisons between trials.

Vagus nerve stimulation allows to cease maintenance electroconvulsive therapy in treatment-resistant depression: a retrospective monocentric case series

Context

The use of vagus nerve stimulation (VNS) to reduce or stop electroconvulsive therapy (ECT) in treatment-resistant depression seems promising. The aim of this study was to investigate the efficacy of VNS on the reduction of ECT sessions and mood stabilization.

Methods

We conducted a monocentric retrospective case series of patients who suffered from treatment-resistant depression, treated with ECT and referred to our center for VNS. We investigated the number and the frequency of ECT sessions before and after VNS implantation. Secondary criteria consisted in the Montgomery Åsberg Depression Rating Scale (MADRS) score, number of medical treatments, dosage of the main treatment and length of hospital stays before and after VNS. Additionally, we sent an anonymous survey to psychiatrists and other physicians in our institution to investigate their knowledge and perception of VNS therapy to treat treatment-resistant depression.

Results

Seven patients benefited from VNS: six (86%) were female (mean age of 51.7 +/- 16.0 years at surgery), and five (71%) suffered from bipolar depression (three type I and two type II). All patients were followed up at least 2 years post-implantation (range: 27-68 months). Prior to VNS, six patients were treated by maintenance ECT. After VNS, three (43%) patients did not require maintenance ECT anymore, and three (43%) patients required less frequent ECT session with a mean 14.7 +/- 9.8 weeks between sessions after VNS vs. 2.9 +/- 0.8 weeks before VNS. At last follow-up, 4 (57%) patients had stopped ECT. Five (71%) patients implanted with VNS were good responders (50% decrease relative to baseline MADRS). According to the survey, psychiatrists had a significantly better perception and knowledge of ECT, but a worse perception and knowledge of VNS compared to other physicians.

Conclusion

VNS is a good option for treatment-resistant depression requiring maintenance ECT dependence. Larger on-going studies will help broaden the implanted patients while strengthening psychiatrists' knowledge on this therapy.

Personal recovery associated with deep brain stimulation for treatment-resistant depression: A constructivist grounded theory study

WHAT IS KNOWN ON THE SUBJECT?: Major depressive disorder is the most prevalent of all mental illnesses. 10%-20% of patients with depression and 1% of the population overall have treatment-resistant depression (TRD). DBS is an emerging investigational treatment for TRD with documented clinical efficacy and safety. The framework of the recovery model includes both clinical and personal recovery. Personal recovery is a self-process in which hope, empowerment and optimism are embraced to overcome the impact of mental illness on one's sense of self. Although clinical and functional outcomes of DBS for TRD have been well documented in the previous studies, personal recovery as an outcome has been explored only in a handful of studies. WHAT THIS PAPER ADDS TO EXISTING KNOWLEDGE?: This is the first qualitative study exploring personal recovery from DBS treatment specific to the target of subcallosal cingulate cortex in patients with TRD. Since the existing literature on personal recovery in DBS studies is limited, the contribution of this paper is crucial to this field. For individuals who responded to deep brain stimulation clinically, neither participants nor family believed it cured their depression, but rather there was a significant decrease in the severity of symptoms of depression. A holistic-oriented framework (that includes personal recovery) is significant for those individuals with TRD undergoing DBS. Personal and clinical recovery are two different constructs, and individuals may experience one or the other or both. The experience of participants who responded to deep brain stimulation recognized that the recovery from depression is a process of reconstructing self. This process involved a period of adjustment that evoked a deeper self-awareness, re-engagement with daily living and newfound gratitude in living. Individuals transitioned from an emotionally driven life to one where future goals were considered. Supportive relationships were instrumental in this process. WHAT ARE THE IMPLICATIONS FOR PRACTICE?: A deep brain stimulation intervention for treatment-resistant depression offered individuals an opportunity for personal recovery where a reconstruction of self occurred. Personal recovery can be considered as an outcome in conjunction with clinical and functional outcomes in future DBS trials for TRD. The relevance of personal recovery in the prevention of relapses needs further investigation. To advocate for care and services that facilitate the process of recovery from depression, it is important to understand the personal dimensions and experience of recovery that may influence the process. To develop recovery-oriented interventions to help patients and families in recovery post-deep brain stimulation, further understanding of support and negotiating relationships during this life-altering experience is needed. ABSTRACT: Introduction Multiple trials of antidepressant treatments in patients with depression pose a major challenge to the mental health system. Deep brain stimulation (DBS) is an emerging and promising investigational treatment to reduce depressive symptoms in individuals with treatment-resistant depression (TRD). The clinical and functional outcomes of DBS for TRD have been well documented in previous studies; however, studies of personal recovery as an outcome of DBS specific to the target of subcallosal cingulate cortex in patients with TRD are limited. Aim To explore the processes of personal recovery in patients with treatment-resistant depression following subcallosal cingulate-deep brain stimulation. Method Participants were 18 patients with TRD who participated in the subcallosal cingulate (SCC)-DBS trial and 11 family members. They also participated in add-on individual cognitive behavioural therapy during the trial. A qualitative constructivist grounded theory approach was used to conceptualize the personal recovery process of patients and families. Results While every participant and their families' journey were unique following the deep brain stimulation intervention, a theoretical model of Balancing to Establish a Reconstructed Self emerged from the data. The themes underlying the model were (1) Balancing to Establish a Reconstructed Self: A Whole-Body Experience, (2) The Liminal Space in-between: Balancing with Cautious Optimism, (3) Hope: Transitioning from Emotion-Focussed Living to Goal-Oriented Planning and (4) Support: Negotiating Relationships. Discussion This is the first study examining recovery from patients' perspectives as an outcome of SCC-DBS intervention for TRD. The study shows that personal recovery is a gradual and continual process of reconstruction of the self, developing through supportive relationships. Clinical and personal recovery are two distinct constructs, and individuals may experience one or the other or both. Most patients who do respond clinically experience improvement in terms of having optimism and hope. Some patients, however, respond with significant symptom reduction but are not able to achieve personal recovery to experience joy or hope for improved quality of living. Implications for Practice Strategies for personal recovery for both patients and family need to be considered during and post deep brain stimulation intervention. Nurses working with these patients and families may benefit from education, training and support to assess and engage in conversations about their recovery process.

Commentary on the Continued Investigational Status of DBS for Psychiatric Indications

Behavioral disorders exact a tragic toll on patients, families, and society. Consequently, the search for better treatments is a public health priority. Recent research promises to lead to advances in psychiatric treatment that may include implantation of deep brain stimulation (DBS) devices. In this commentary, the authors discuss how promising results from initial pilot studies of DBS in treatment-resistant depression (TRD) were not validated in 2 randomized, controlled, multicenter trials. Reliance on pilot data may have contributed to the selection of primary efficacy endpoints that were not achieved, and to the underestimation of adverse events and device-related complications. Published data on the population prevalence of affective disorders also may have led sponsors to overestimate the number of patients with TRD who were candidates for DBS therapy. Consequently, a more complete discussion of certain aspects of the depression trials may allow a realistic appraisal of the clinical and ethical situation of DBS therapy for TRD in a US regulatory context. A US regulatory perspective also may clarify the clinical research and reimbursement consequences of the Humanitarian Device Exemption (HDE) approval status of DBS for obsessive-compulsive disorder (OCD). Retrospective analyses akin to failure modes and effects analysis in engineering may clarify unexpected results in the DBS depression trials. Recent research suggests that subject selection in future trials may be augmented by advanced neuroimaging methods. For the present, the noncommercial research status of DBS to treat depression and the HDE status for OCD appear likely to remain in place.

Long-Term Results of Deep Brain Stimulation for Treatment-Resistant Depression: Outcome Analysis and Correlation With Lead Position and Electrical Parameters

BACKGROUND

Long-term efficacy and mechanisms of action of deep brain stimulation (DBS) for treatment-resistant depression (TRD) are under investigation.

OBJECTIVE

To compare long-term outcomes with active electrode's coordinates and its electrical parameters in patients with TRD treated with DBS in the subgenual cingulate gyrus (SCG-DBS).

METHODS

Seventeen patients with TRD underwent SCG-DBS. Demographic and baseline characteristics were recorded. The 17-item Hamilton Depression Rating Scale was used to measure the response to the therapy. The anterior commissure-posterior commissure coordinates of the active contacts and the total electrical energy delivered were calculated and correlated with clinical outcomes. Patient-specific tractographic analysis was performed to identify the modulated pathways in responders.

RESULTS

Twelve women (70.6%) and 5 men (29.4%) with a median age of 48 yr (34-70 years) were included. Along the 5-year follow-up, 3 main clinical trajectories were observed according to symptom's improvement: great responders (≥80%), medium responders (≥50%-79%), and poor responders (<50%). Active contacts' coordinates and total electrical energy delivered showed no correlation with clinical outcomes. Brodmann area 10 medial was the most frequently stimulated area and the forceps minor, the most frequently modulated tract.

CONCLUSION

SCG-DBS for TRD is clearly effective in some patients. Active contacts' coordinates were highly variable within the region and, like electrical parameters, did not seem to correlate with clinical outcomes. In the current series, Brodmann area 10 medial and the forceps minor were the most frequently targeted area and modulated pathway, respectively.