Can Neurofeedback Help Anxiety and Mood? – BrainWorks Holistic Therapy

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Neurofeedback and Biofeedback for Mood and Anxiety Disorders: A Review of Clinical Effectiveness and Guidelines

CADTH Rapid Response Report: Summary With Critical Appraisal

Srabani Banerjee and Charlene Argáez.

Ottawa (ON): Canadian Agency for Drugs and Technologies in Health; 2017 Nov 13.

Context and Policy Issues

Mood and anxiety disorders are among the common types of mental disorders in Canada. ¹ According to a 2013 estimate for Canada, three million (11.6%) people of age 18 years or older reported that they had a mood and/or anxiety disorder.¹ Mood and anxiety disorders include various psychiatric disorders of which post-traumatic disorder (PTSD), generalized anxiety disorder (GAD) and depression are the focus of this review. These are debilitating conditions and associated with considerable personal, societal and economic costs.²^–⁴ PTSD involves recurring intrusive recollections of a traumatic event, with recollections beginning within the firstsix months and lasting over one month. ⁵ GAD is characterized by intense anxiety and worry regarding several events or activities that persist most days during at leastsix months and is difficult to control.⁶ Depressive disorders are characterized by severe and persistent sadness which interferes with normal function and frequently results in lack of interest or pleasure in activities.⁷ Treatment options for these disorders generally include pharmacotherapy or psychotherapy. However, not all patients respond to these therapies and some patients may experience adverse effects.⁸

Biofeedback (BF) is a non-invasive psychophysiological treatment technique with a bio-monitoring system and sensors to measure, amplify, and feedback information that enables an individual to learn how to change physiological activity (such as respiration, heart rate variability, blood flow and blood pressure) and thus improve health and performance.⁹^–¹¹ There is some speculation regarding home use BF devices. Home use BF device may allow an individual to self-treat in the comfort of their home and decrease travel to clinics to receive training; however, visits with the health professional may still be needed and adherence may be an issue for some individuals.

Neurofeedback is a specific type of biofeedback.¹² Neurofeedback focusses on the central nervous system and the brain to improve neuro regulation and stabilization.¹³^,¹⁴ Modulation of brain activity can affect behavioral changes.¹⁵ NF trains the patient to improve poorly regulated brainwave patterns by using computer technology.¹¹ Feedback is provided to the patient in real time using sounds or video images; positive feedback or negative feedback depending on whether the desired brain activity is achieved or not achieved.¹¹ There appears to be some debate regarding the therapeutic role of biofeedback and neurofeedback for the treatment of patients with psychiatric disorders.⁸^,¹⁵

Two previous CADTH Rapid Response reviews¹⁰^,¹⁶ reported on neurofeedback and biofeedback for mood and anxiety disorders. The review¹⁰ published in 2012 reported that evidence from mostly preliminary analyses suggested that neurofeedback and biofeedback may have potential for the treatment of PTSD, GAD, or depression. The review¹⁶ published in 2014, assessed evidence identified since the publication of the review¹⁰ of 2012 and reported that limited evidence suggested that biofeedback may decrease the symptoms of PTSD or depression. Both the reviews¹⁰^,¹⁶ reported that no relevant evidence based guidelines on neurofeedback or biofeedback were identified. The purpose of this review is to evaluate the more recent evidence regarding the clinical effectiveness of neurofeedback or biofeedback compared with other modalities for the treatment of mood and anxiety disorders (PTSD, GAD, or depression) in adults. Additionally, this review aims to review recent evidence-based guidelines regarding the use of neurofeedback or biofeedback for the treatment of mood and anxiety disorders (PTSD, GAD, or depression) in adults.

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Research Question

What is the clinical effectiveness of neurofeedback provided by a health professional for mood or anxiety disorders in adults?
What is the clinical effectiveness of biofeedback provided by a health professional for mood or anxiety disorders in adults?
What is the clinical effectiveness of biofeedback using home equipment for mood or anxiety disorders in adults?
What are the evidence-based guidelines regarding the use of neurofeedback or biofeedback for the treatment of mood and anxiety disorders in adults?

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Key Findings

Evidence from single randomized controlled trials suggests that compared with no treatment there is a statistically significant improvement in symptoms with neurofeedback treatment in patients with post-traumatic stress disorder (PTSD) or generalized anxiety disorder (GAD).

A single randomized controlled trial (RCT) showed that for patients with PTSD there was improvement in symptoms with biofeedback (BF) plus treatment as usual (TAU) and also with TAU alone but the improvement occurred faster in the BF plus TAU group. A single RCT showed that for patients with PTSD there were no between group differences for BF and various mindfulness related treatment modalities.

A single RCT showed that for patients with major depressive disorder, there was a statistically significant improvement in depression with BF plus TAU.

Results need to be interpreted in the light of limitations (such as small sample size, lack of randomization details, lack of reporting of adverse events, lack of long-term data).

No relevant studies on the clinical effectiveness of biofeedback using home equipment for treatment of PTSD, GAD, or depression without continued support from health professionals were identified.

No relevant evidence based guidelines regarding the use of neurofeedback or biofeedback for the treatment of PTSD, GAD, or depression were identified.

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Methods

Literature Search Methods

This report makes use of a literature search developed for a previous CADTH report. The original literature search was conducted in July 2014 on key resources including Medline, PubMed, PsycInfo, and The Cochrane Library, University of York Centre for Reviews and Dissemination (CRD) databases, Canadian and major international health technology agencies, as well as a focused Internet search. No filters were applied to limit the retrieval by study type. Where possible, retrieval was limited to the human population. The initial search was also limited to English-language documents published between January 1, 2012 and July 28, 2014. For the current report, database searches were rerun on October 16, 2017 to capture any articles published since the initial search date. The search of major health technology agencies was also updated to include documents published since July 2014.

Selection Criteria and Methods

One reviewer screened citations and selected studies. In the first level of screening, titles and abstracts were reviewed and potentially relevant articles were retrieved and assessed for inclusion. The final selection of full-text articles was based on the inclusion criteria presented in Table 1.

Table 1

Selection Criteria.

Exclusion Criteria

Articles were excluded if they did not meet the selection criteria outlined in Table 1, they were duplicate publications, or were published prior to 2014. For articles published in 2014, there may be possibility of some overlap of articles identified in the previous CADTH report¹⁶ literature search and in this current report, hence articles identified by the current literature search which were already included in the previous review ¹⁶ were not considered here. Studies comparing different NF methods (such as using different brain locations) were excluded. Guidelines that were not evidence-based were excluded.

Critical Appraisal of Individual Studies

The included randomized studies were critically appraised using Downs and Black checklist.¹⁷ Summary scores were not calculated for the included studies; rather, a review of the strengths and limitations of each included study were narratively described.

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Summary of Evidence

Quantity of Research Available

A total of 368 citations were identified in the literature search. Following screening of titles and abstracts, 350 citations were excluded and 18 potentially relevant reports from the electronic search were retrieved for full-text review. No potentially relevant publications were retrieved from the grey literature search. Of these potentially relevant articles, 13 publications were excluded for various reasons, while five publications met the inclusion criteria and were included in this report. These comprised five randomized controlled trial (RCT) reports.⁶^,¹⁴^,¹⁸^–²⁰ Appendix 1 describes the PRISMA flowchart of the study selection.

Summary of Study Characteristics

Study characteristics are summarized below and details are presented in Appendix 2, Tables 2 and 3.

Study Design

All five included studies were RCTs.⁶^,¹⁴^,¹⁸^–²⁰ In one RCT⁶ the psychiatrist conducting the diagnostic interview at the beginning and at the end of the study was blinded. In one RCT²⁰ the investigator conducting the analysis was blinded. In three RCTs ¹⁴^,¹⁸^,¹⁹ blinding was not mentioned.

Country of Origin

Of the five RCTs, two RCTs¹⁴^,²⁰ were published in 2016 from the USA and three RCTs were published in 2015, one each from Iran,⁶ the Netherlands,¹⁹ and the USA.¹⁸

Patient Population

Three RCTs¹⁴^,¹⁹^,²⁰ were on PTSD patients, the number of patients ranged between 8 and 102. The proportions of females were 75% and 76% in two RCTs ¹⁴^,¹⁹ on patients with chronic PTSD and 6% in one RCT²⁰ on combat veterans with PTSD. The mean age was 52 years in one RCT,²⁰ and 44 years in one RCT¹⁴; the median age was 45 years in one RCT.¹⁹

One RCT⁶ was on 28 patients of mean age 30 years and with GAD. The proportion of males or females was not reported.

One RCT¹⁸ was on 20 patients of mean age 20 years with major depressive disorder (MDD). The proportion of males or females was not reported.

Interventions and Comparators

Of the five RCTs, three RCTs¹⁸^–²⁰ investigated BF and two RCTs⁶^,¹⁴ investigated NF. Study duration ranged from six to 12 weeks.

PTSD

One RCT²⁰ compared four treatment modalities: (i) body scan mindfulness meditation (MM), (ii) slow breathing using a biofeedback device (SB), (iii) mindful awareness of breadth with the intent to do slow breathing (MMSB), and (iv) sitting quietly (SQ). One RCT¹⁴ compared neurofeedback (NF) with no treatment (i.e., waitlist [WL]). Patients in the WL group did not receive treatment during the study but had the option of receiving NF treatment after the study was completed. One RCT¹⁹ compared biofeedback (BF) plus treatment as usual (TAU) with TAU alone. TAU was trauma-focused cognitive behavioral therapy (CBT).

GAD

One RCT⁶ compared NF with WL. Patients in the WL group did not receive treatment during the study but had the option of receiving NF treatment after the study was completed.

MDD

One RCT¹⁸ compared heart rate variability biofeedback (HRV-BF) plus TAU with TAU alone. TAU was psychotherapy; details were not reported.

Outcomes

All five RCTs⁶^,¹⁴^,¹⁸^–²⁰ reported on psychological outcomes using various outcome measures, that are specified below according to disease condition. Descriptions of the outcome measures are presented in Appendix 2 Table 3.

PTSD

In one included RCT²⁰ the outcome measures used were Beck Depression Inventory-II (BDI-II), Global Impression of Change (GIC), General Perceived Self-Efficacy scale (GPSE), Positive and Negative Affect Scale (PANAS), PTSD checklist (PCL), Pittsburgh Sleep Quality Index (PSQI), and Perceived Stress Scale (PSS). In the second RCT¹⁴ the outcome measures used were Clinician Administered PTSD Scale (CAPS), Davidson Trauma Scale (DTS), Inventory of Altered Self-Capacities (IASC). In the third RCT¹⁹ the outcome measure used was Impact of Event Scale-Revised (IES-R).

GAD

In included RCT⁶ the outcome measures used were General Anxiety Disorder scale(GAD-7), and Global Assessment Functioning Scale (GAFs).

MDD

In the included RCT¹⁸ the outcome measures used were BDI-II and Outcome Questionnaire (OQ-45).

Summary of Critical Appraisal

The critical appraisal of the included RCTs is summarized below and details are available in Appendix 3, Table 4.

In all five included RCTs ⁶^,¹⁴^,¹⁸^–²⁰ the objective, and inclusion and exclusion criteria were stated, the patient characteristics, interventions and outcomes were described. However details of the randomization procedure were lacking, hence it was unclear if there was any selection bias. The RCTs had restrictive inclusion criteria hence generalizability to a broader patient population other than the study population is unclear. Additional details of the critical appraisal are presented separately for each of the three conditions.

PTSD

Additionally, in all three included RCTs of patients with PTSD¹⁴^,¹⁹^,²⁰ mixed model or multilevel model analyses were conducted, as such analyses are not affected by patient attrition or missing data. In one RCT²⁰ the investigator who did the data analysis was blinded and in the other two RCTs¹⁴^,¹⁹ it was unclear if there was any blinding. In one RCT²⁰ sample size calculation was undertaken and the appropriate number was used, one RCT¹⁴ was slightly underpowered but treatment effects were statistically significant, hence no issue, and in one RCT¹⁹ it was unclear if sample size calculation had been undertaken. In two RCTs¹⁴^,¹⁹ the authors stated that there were no conflicts of interest, and in one RCT²⁰ conflicts of interest were not mentioned.

GAD

Additionally, in the included RCT of patients with GAD⁶ the psychiatrist assessing the patient pre- and post-treatment was blinded. It was unclear if sample size calculation had been undertaken, if there were any withdrawals, if an intention-to-treat analysis had been undertaken, or if there were any conflicts of interest.

MDD

Additionally, in the included RCT of patients with MDD¹⁸ it was unclear if there was any blinding, if sample size calculation had been undertaken, if there were any withdrawals, if an intention-to-treat analysis had been undertaken, or if there were any conflicts of interest.

Summary of Findings

Findings are summarized below and details are available in Appendix 4, Table 5.

What is the clinical effectiveness of neurofeedback provided by a health professional for mood or anxiety disorders in adults?

PTSD

The RCT by van der Kolk et al.¹⁴ involving adults with chronic PTSD, compared patients on NF treatment with patients awaiting treatment (i.e., NF versus waitlist [WL]). Both groups showed a statistically significant decrease in PTSD symptoms (as assessed using CAPS) between pre-treatment and 1-month post-treatment, however the decrease was greater for the NF group (decrease in CAPS score: 40.35 for NF and 10.78 for WL). A decrease in CAPS score by 20 is commonly considered as clinically significant. Also, at 1-month post-treatment, there were statistically significant improvements in PTSD symptoms with NF compared to WL, as assessed using DTS and IASC scores.

GAD

The RCT by Dadashi et al.⁶ compared NF with WL for management of adult patients with GAD. It showed that treatment with NF resulted in a statistically significant increase in the global functioning level and reductions in symptoms of GAD, but such changes were not observed in the WL group.

What is the clinical effectiveness of biofeedback provided by a health professional for mood or anxiety disorders in adults?

PTSD

The RCT by Polak et al.¹⁹ compared treatments with BF plus TAU with TAU alone in adults with chronic PTSD. TAU comprised trauma focused CBT. It showed that PTSD symptoms (assessed using IES-R scores) decreased over time for both BF + TAU and TAU treatments, but PTSD symptoms decreased faster with BF + TAU treatment compared with TAU alone (P = 0.051).

The RCT by Wahbeh et al.²⁰ compared MM, SB, MMSB, and SQ for the treatment of adults (combat veterans) with chronic PTSD. Compared to pre-treatment, improvements in some PTSD and related symptoms were observed within each group and appeared to be greatest in the MM group followed sequentially by MMSB, SQ and then SB. For MM, improvements appeared to be statistically significant but for MMSB, SQ, and SB statistically significance was achieved for some outcome measures and not for other outcome measures. The analyses were based on available data and missing data or covariates were not considered. Mixed model analyses showed that overall there were no between-group differences on PTSD symptoms, perceived stress, depression, positive and negative emotions, self-efficacy, and sleep quality.

MDD

The RCT described in the dissertation by Caldwell¹⁸ compared treatments with HRV-BF plus TAU with TAU alone in young adult patients with MDD. TAU comprised psychotherapy. This study showed that there was a statistically significant decrease in depression levels (measured using BDI-II and OQ-45) between baseline and post treatment follow-up in the MDD patients receiving HRV-BF in addition to TAU. However, in the MDD patients receiving only TAU there appeared to be a decrease in depression levels between baseline and post treatment follow-up but the difference was not statistically significant. The statistical significance of between group differences was not presented.

What is the clinical effectiveness of biofeedback using home equipment for mood or anxiety disorders in adults?

No relevant studies on the clinical effectiveness of BF using home equipment for treatment of mood and anxiety disorders (PTSD, GAD, or depression) without continued support from health professionals were identified. In three RCTs,¹⁸^–²⁰ between the scheduled visits with health professionals, the patients were instructed to practice at home the training they had received using BF devices or visual guides. These findings have been presented for question 2 (above).

What are the evidence-based guidelines regarding the use of neurofeedback or biofeedback for the treatment of mood and anxiety disorders in adults?

No relevant evidence-based guidelines regarding the use of NF or BF for the treatment of mood and anxiety disorders (PTSD, GAD, or depression) were identified.

Limitations

No relevant health technology assessments, systematic reviews, and non-randomized studies comparing NF or BF with other modalities for treatment of PTSD, GAD, or depression were identified. In addition, no evidence-based guidelines on NF or BF for treatment of PTSD, GAD, or depression were identified.

A limited number of relevant RCTs were available. The inclusion criteria of the studies were restrictive. Patients with co-morbidities (such as other psychological conditions) were excluded. Hence generalizability of the findings is uncertain.

Comparisons across studies were difficult as the comparators, disease conditions and outcome measures were variable.

The majority of the studies (three of the five included studies) were of small sample size (ranging from 8 to 28). Hence there is potential for underestimation or overestimation of results.

Long term effects of treatments with BF and NF were unclear. For most RCTs, the treatment duration ranged from six weeks to eight weeks with no further follow-up; except in one RCT the treatment duration was12 weeks with one month follow-up post treatment.

None of the studies reported on adverse events.

None of the studies were conducted in Canada hence generalizability to the Canadian setting is limited. However four of the five included studies were from the USA or Europe, hence there may be some similarities.

Findings need to be interpreted in the light of the limitations presented above.

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Conclusions and Implications for Decision or Policy Making

Five relevant RCTs.⁶^,¹⁴^,¹⁸^–²⁰ comparing NF or BF with other psychological treatments or no treatments for managing patients with PTSD, GAD or MDD were identified. Of these five RCTs, two RCTs⁶^,¹⁴ were on NF provided by health professionals, and three RCTs¹⁸^–²⁰ were on BF provided by health professionals. No relevant studies on the clinical effectiveness of biofeedback using home equipment for treatment of PTSD, GAD, or depression without continued support from health professionals were identified. No relevant evidence based guidelines regarding the use of NF or BF for the treatment of PTSD, GAD, or depression were identified.

The results from two RCTs (one study per condition) suggested that NF may be effective for the treatment of PTSD¹⁴ or GAD⁶ compared with no treatment.

Some evidence was identified to suggest that adding BF to TAU may be more effective than TAU alone. For patients with PTSD, one RCT showed that adding BF to trauma-focused CBT was associated with faster improvements in symptoms than CBT alone,¹⁹ while another RCT found no significant differences between BF and mindfulness-based therapies.²⁰ For patients with MDD, one RCT found that patients who received HRV-BF in addition to psychotherapy showed significant improvements in symptoms after treatment, while significant improvements were not achieved with psychotherapy alone.¹⁸

Findings need to be interpreted in the light of the limitations (such as small sample size, limited number of relevant studies, lack of randomization details, lack of reporting of adverse event, and lack of long-term data).

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