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Breathing Practices for Treatment
of Psychiatric and Stress-Related
Medical Conditions
Richard P. Brown, MD
a
, Patricia L. Gerbarg, MD
b,
*,
Fred Muench, PhD
c
INTRODUCTION
Research on breathing techniques is generating new treatments for stress reduction,
anxiety disorders, depression, posttraumatic stress disorder (PTSD), attention-deficit
Disclosures: R.P. Brown and P.L. Gerbarg: codeveloped the Breath-Body-Mind program and
sometimes receive financial remuneration for teaching it; F. Muench: Dr Muench codeveloped
the iPhone application, BreathPacer, but as of 2013 no longer receives royalties from the
company marketing it.
a
Department of Psychiatry, Columbia University College of Physicians and Surgeons, 86 Sherry
Lane, New York, NY 12401, USA;
b
Department of Psychiatry, New York Medical College, 86
Sherry Lane, Valhalla, NY 12401, USA;
c
Columbia University College of Physicians and
Surgeons, 3 Columbus Circle, Suite 1404, New York, NY 10017, USA
* Corresponding author.
E-mail address: PGerbarg@aol.com
KEYWORDS
Paced breathing Pranayama Resonance breathing Coherent breathing Yoga
Qigong Anxiety Depression
KEY POINTS
Neuroanatomic and brain imaging studies reveal breath-activated pathways to all major
networks involved in emotion regulation, cognitive function, attention, perception, subjec-
tive awareness, and decision making.
Specific breath practices have been shown to be beneficial in reducing symptoms of
stress, anxiety, insomnia, posttraumatic stress disorder, obsessive-compulsive disorder,
depression, attention deficit disorder, and schizophrenia.
The risks of adverse reactions to breath practices can be minimized through patient
assessment and by limiting the use of stimulating practices in vulnerable individuals.
Technology-assisted breath retraining devices range from mobile phone pacing applica-
tions to physiologic biofeedback machines designed to foster therapeutic breath prac-
tices using audiovisual cues and/or physiologic feedback.
Technology-assisted breath retraining offers alternative or adjunctive methods to clients
who are interested in breathing practices.
Ideally, initial technology-assisted breath retraining should be accompanied by in-person
guided instruction and evaluation.
Psychiatr Clin N Am 36 (2013) 121–140
http://dx.doi.org/10.1016/j.psc.2013.01.001 psych.theclinics.com
0193-953X/13/$ – see front matter Ó2013 Elsevier Inc. All rights reserved.
disorder, and stress-related medical conditions. Breathing practices can ameliorate
aberrations in sympatho-vagal balance, stress response, emotion regulation,
and neuroendocrine function associated with these conditions. The first part of this
article describes evidence-based breath practices for mental health care; the
second part reviews technology-assisted breathing interventions. For each tech-
nique, the research support, clinical applications, and the risks and benefits are
discussed.
BREATHING PRACTICES: DEFINITIONS AND CONTEXTS
Breathing practices entail voluntary changes in the rate, pattern, and quality of respi-
ration. Many Eastern traditions consider breath practices to be fundamental to phys-
ical, emotional, and spiritual development (see article in this publication by Telles and
Singh). Until recently, the centrality of breath work had been largely lost in transition
from East to West. Each practice has innumerable variations, producing different
psychophysiological effects.
1,2
The terms yoga or yogic breathing are used to encom-
pass all of the forms described throughout this discussion.
Paced breathing requires controlling the respiratory rate and the relative length of
4 phases of the breath cycle.
In coherent or resonance breathing, the length of inhalation and exhalation
are equal with only a slight pause between. Other forms use counts, for ex-
ample, 4 counts in, 4 counts breath hold, 6 counts out, and 2 counts breath
hold.
Resistance breathing creates partial obstruction to airflow using laryngeal
contracture, vocal cords, pursed lips, or other means, which produces sounds
and vibrations.
Unilateral or alternate nostril breathing involves closing one nostril such that all air
flows through the other.
Moving the breath engages the imagination to move one’s breath through
different parts of the body.
Breathing with movement coordinates paced breathing with physical
movements.
Yoga styles vary in their emphasis on breathing, movement, and meditation. Iyengar
yoga focuses on body alignment with breath practices, Vinyasa on breath-linked
movement,
3
and Shavasana on relaxation and rhythmic breathing. Sudarshan Kriya
yoga (SKY) includes 5 breath practices:
1. Resistance breath (Ujjayi)
2. Omchant
3. Bellows breath (Bhastrika)
4. Sudarshan Kriya (SK) cyclical breathing at varying rates
5. Alternate nostril breathing (ANB)
Qigong and Tai Chi entail body movements, breath exercises, and meditation to
circulate vital energy (Qi or Chi). Breath-body-mind, a modern adaptation, combines
coherent breathing, resistance breathing and breath moving (a qigong meditative
practice most highly developed by eleventh century Russian Orthodox Christian
monks).
4
Thich Nhat Hanh (2009) allows the breath to slow down naturally by placing
awareness on the breath during meditation. Theravadin Buddhism emphasizes medi-
tative breathing, such as anapanasati.
5
Tibetan Buddhist breath practices are consid-
ered to be so sacred that they are rarely seen in the West.
Brown et al
122
PUTATIVE PHYSIOLOGIC MECHANISMS OF ACTION
An evolving neurophysiological model for the effects of breath practices has been
described previously.
6–8
Research demonstrates that yoga breathing can modulate
autonomic nervous system (ANS) function, stress responses, cardiac vagal tone, heart
rate variability (HRV), vigilance, attention, chemoreflex and baroreflex sensitivity,
central nervous system excitation, and neuroendocrine functions.
9
Slow breathing
at 4.5 to 6.5 breaths per minute (coherent or resonance breathing) has been shown
to optimally balance sympatho-vagal stress response for most adults.
10–13
Imbalances of the ANS, including decreased parasympathetic nervous system
(PNS) activity and increased sympathetic nervous system (SNS) activity, underactivity
of the inhibitory neurotransmitter, gamma amino-butyric acid (GABA), and increased
allostatic load (the cost to the organism to adapt to conditions outside the usual
homeostatic range) are associated with depression, anxiety, PTSD, and other psychi-
atric disorders. These conditions are exacerbated by stress and are characterized by
low PNS and low GABA activity. Streeter and colleagues
8
hypothesized that yoga
practices are associated with the following effects:
1. Correction of the underactivity of the PNS and GABA system in part through stim-
ulation of the vagal nerves, the main pathway of the PNS
2. Reduction of allostatic load resulting in symptom relief
The om chant involves slow breathing, airway resistance (contracting the vocal
cords to generate sound), and vibrational effects, which increase vagal tone and phys-
iologic relaxation.
14
A functional magnetic resonance imaging study showed signifi-
cant limbic system deactivation with om chanting.
15
Stress and PTSD are associated with decreased hippocampal GABA levels,
prefrontal cortex (PFC) underactivity, amygdalar overactivity, and low HRV.
6,8
Because the underactive PFC fails to inhibit the overactive amygdala (as in PTSD),
emotions become dysregulated and limbic defensive reactions emerge. The insular
cortex in the sylvian fissure between the temporal and frontal lobes also sends inhib-
itory GABAergic projections to the central extended amygdala. Fig. 1 shows neural
circuits and anatomic structures with GABA receptors that are hypothesized to regu-
late stress response systems. It has been proposed that interoceptive information
(sensory information from inside the body) may be conveyed by the PNS via the
nucleus tractus solitarius to the insular cortex creating a map of the internal state of
the body that may be the substrate for perception and subjective experience of the
inside of the body.
16
Changes in breathing patterns alter the interoceptive messages
from the body traveling primarily through the vagus nerves to critical regulatory brain
centers. When millions of sensors throughout the respiratory system (nose, throat,
lungs, bronchial tree, diaphragm, and thorax) send signals, the brain responds with
rapid and widespread shifts in activation, attention, perception, emotion regulation,
subjective experience, and behavior.
8,9
Theoretically, yoga breathing stimulates an underactive PNS, increasing the inhibi-
tory action of a hypoactive GABA system in brain pathways and structures that are
critical for threat perception, emotion regulation, and stress reactivity. Increased inhib-
itory GABA transmission from the PFC and/or the insular cortex could reduce overac-
tivity in the amygdala and the associated psychological and somatic symptoms of
PTSD (see Fig. 1).
8
Vagal pathways to the central PNS also lead to the anterior cingu-
late,
16
which is involved in evaluation, decision making, emotion regulation, fear
extinction, and inhibition of amygdalar reactivity.
17
The hypothalamic-pituitary-
adrenal axis is also influenced by the PNS via connections with the hypothalamus,
Mind-Body: Breathing Practices for Stress-Related Conditions 123
amygdala, and hippocampus (see Fig. 1). Yoga practices are associated with reduced
levels of stress markers, including cortisol.
18,19
Evidence suggests that vagal activa-
tion also increases the release of prosocial hormones, oxytocin, vasopressin, and
prolactin, which may contribute to the increase in feelings of love, bonding, empathy,
and meaning reported by many yoga practitioners.
20
Breath practices can affect key
anatomic structures and neural pathways involved in the regulation of emotion, atten-
tion, perception, and problem solving.
SELECTED STUDIES OF BREATH PRACTICES FOR PSYCHIATRIC CONDITIONS
Yoga and other mind-body traditions use movement, breathing, meditation, and other
practices. This review includes open and controlled trials of breath practices alone and
multicomponent interventions that emphasize breath practices.
3
Stress Management
Four randomized controlled trials (RCTs) and one open study of slow-paced breathing
show reduction in symptoms of stress, anxiety, anger, exhaustion, depression, and
improvement in quality of life associated with increased HRV, indicating activation
of vagal PNS pathways (Table 1).
18,21–24
Anxiety Disorders, Generalized Anxiety Disorder, Insomnia
Seven studies, including 2 RCTs, 2 controlled trials (CTs), and 3 open pilots, found
significant reductions in anxiety with breath-focused yoga programs (see
Table 1).
25–31
Fig. 1. Neuroanatomic connections of parasympathetic nervous system with GABA system.
(From Streeter CC, Gerbarg PL, Saper RB, et al. Effects of yoga on the autonomic nervous
system, gamma-aminobutyric-acid, and allostasis in epilepsy, depression, and post-
traumatic stress disorder. Medical Hypotheses 2012;78(5):571–9; with permission.)
Brown et al
124
Generalized anxiety disorder
Two pilot studies evaluated yoga programs for severe treatment-resistant generalized
anxiety disorder with comorbidities. In the first study (n 531) using the 22-hour SKY
program, the response rate was 73% and the remission rate was 41%.
25
The second
study (n 520) using the breath-body-mind 12-hour program of breath practices,
qigong, and open focus meditation
32
resulted in significant improvements in anxiety,
sleep, and depression.
26
PTSD
Studies of yoga programs emphasizing breath practices for PTSD (3 RCTs, one CT,
and 2 open pilots) found significant improvements in PTSD, anxiety, and depression
among survivors of partner abuse, mass disasters, and military service.
33–37
Mass disasters
Nonprofit organizations have provided yoga programs in disaster areas for decades.
Problems of safety and access may account for the paucity of mind-body studies.
Nevertheless, a small number of studies demonstrate feasibility, efficacy, and safety
of low-cost mind-body treatments for populations affected by mass disasters. In
a nonrandomized controlled study, 183 refugees of the 2004 Asian tsunami were
assigned by camps to 3 groups:
1. Eight-hour yoga-breath (Breath Water Sound [BWS])
2. BWS plus 3 to 8 hours an exposure therapy called Traumatic Incident Reduction
(TIR)
3. Six-week wait list
After 6 weeks, BWS alone and BWS plus TIR reduced the Posttraumatic Stress
Disorder Check List-17 (PCL-17) scores by more than 60% and the Beck Depression
Index (BDI) more than 90% compared with no change in the control. Most improve-
ments occurred within the first week, with further gains by the 24-week follow-up.
33
Trauma-sensitive programs have been readily accepted by diverse cultures.
35
Military service related trauma
Among military personnel and veterans, mind-body practices can relieve symptoms of
stress, depression, and PTSD. In a rater-blind RCT of 30 Australian Vietnam veterans
on disability caused by chronic PTSD, those given a 5-day SKY course had significant
reductions on the Clinician Administered PTSD Scale (CAPS) compared with the wait-
list control at week 6 and additional substantive improvement at 24 weeks.
37
Insomnia
Pharmacotherapy for insomnia in geriatric populations entails risks of confusion, cogni-
tive impairment, syncope, and fractures. Mind-body techniques improve sleep safely
as show in one RCT.
38
Controlled studies with objective sleep measures are needed.
Depression
A review of yoga for depression reported positive findings in 5 RCTs and advised an
optimistic but cautious interpretation.
39
Depression studies with major yoga breathing
components include 3 RCTs and 2 open pilots.
40–44
Yoga improved mood in people
suffering from clinical depression and increased mental and physical energy, alert-
ness, enthusiasm, and positive mood in healthy individuals.
Obsessive-Compulsive Disorder
ANB usually has a calming effect within 10 minutes. In one RCT and one open trial,
patients with obsessive-compulsive disorder (OCD) who were taught Kundalini yoga
Mind-Body: Breathing Practices for Stress-Related Conditions 125
Table 1
Breathing practice effects on anxiety, PTSD, OCD, and depression
Study Design Subjects Method: Interventions/Controls Length Outcome
STRESS RESPONSE
Sakakibara and
Hayano,
21
1996
RCT 30 Healthy college students Audio paced breathing before
electric shock
INT 1: rate 8 bpm
INT 2: 15 bpm
CON: nonpaced
5 min INT 1 [HF-HRV
INT 2 YHRV
CON YHRV
Malathi and
Damodaran,
22
1999
RCT 50 Medical students
examination stress
aged 18–19 y
INT 1: yoga postures, breathing,
prayer, visualization,
meditation
INT 2: reading
Tested on examination day
3 mo Yoga group
YSTAI
(P<.001)
Nolan et al,
23
2005 RCT 46 CHD after MI or
abnormal stress test
INT 1: paced breathing at 6 bpm
with HRV feedback
INT 2: relaxation response,
autogenic, CBT
5 Sessions
1.5 h each
Similar improvement
INT 1 & INT 2
PSS & CES-D
Granath et al,
18
2006 RCT 40 Swedish employees INT 1: Kundalini: postures,
breathing, prayer
INT 2: CBT
4 mo INT 1 & 2 Similar Yin stress, anger,
exhaustion, QOL
Gerbarg et al,
24
2012 Open 84 Health care providers
Mississippi after oil spill
BBM training: qigong, coherent
breath, resistance breath,
breath moving
3d
18 h
Test d 3 & wk 6
YPSS, EIFI
MABI, no change
Afonso et al,
74
2012 RCT 61 Postmenopausal women
with insomnia aged 50–65 y
44 completed
2 sessions per wk
1 h per session
INT 1: yoga stretches 1fast
breathing, relaxation
INT 2: passive stretching
CON: wait list
Tested at 4 mo INT 1 greatest YInsomnia,
anxiety, depression,
QOL, climacteric symptoms
Brown et al
126
ANXIETY, INSOMNIA
Sahasi et al,
28
1989 nrCT 91 Anxiety neurosis INT 1: yoga postures, breath, rest
40 min qd
INT 2: diazepam
3mo YIPAT greater with yoga (P<.05)
Sharma et al,
29
1991 RCT 71 Anxiety neurosis INT: yoga
CON: placebo capsule
1 wk Training 1
daily practice
YHAM-A greater with yoga
Manjunath and
Telles,
38
2005
RCT 69 Elderly (aged >60 y)
Insomnia
INT1: yoga multi-component
INT2: Ayurvedic herbs
CON: wait list
6 wk INT1 [60 min sleep time P<.05
INT2 & CON no change
Kuttner et al, 2006 RCT 28 (8 boys/12 girls) adolescents
(aged 11–18 y) with IBS
INT: yoga 17 postures 1deep
breathing
CON: wait list
1 hr Training 1
4 wk daily home
practice with
video
INT trend toward Ypain YGI
symptoms, avoidance, RCMAS,
FDI, PCQ, CDISF
Telles et al,
30
2007 Pilot 47 Andaman Island survivors
of 2004 tsunami
Ashtanga postures, breathing,
meditation
1wk Yfear, anxiety, sadness, insomnia
P<.05
Kozasa et al,
27
2008 CT
Open
22 Adults c/o anxiety but with
no psychiatric diagnoses
INT: Siddha Samadhi yoga:
11 breathing practices 4/2/5/2
n514
CON: wait list n 58
1mo
40 min per d
INT YSTAI YBDI Ytension [well-
being
Telles et al,
31
2010 RCT 22 Bihar flood survivors
with PTSD
INT: like Ashtanga but with more
breath practice
CON: wait
1 h per d for 1 wk INT Ysadness
CON: [anxiety
Katzman et al,
25,26
2012
Pilot
Open
31 Adults severe
treatment-resistant
GAD comorbidities
INT: SKY 6 d training 120 min
daily home practice
Tests
6 wk and
6mo
YHAM-A,
YASI, YBAI
PSWQY
all P<.001
Katzman et al,
26
2011 Pilot
Open
20 Adults severe
treatment-resistant
GAD comorbidities
BBM 12 h 2 d training 1group F/U
sessions 60 min twice
a month 1daily home practice
20 min
Tests
6 wk and 6 mo
YBAI, ASI, BDI
all P<.001
PSWQ P<.01
(continued on next page)
Mind-Body: Breathing Practices for Stress-Related Conditions 127
Table 1
(continued)
Study Design Subjects Method: Interventions/Controls Length Outcome
POST-TRAUMATIC STRESS DISORDER
Descilo et al,
33
2010 nrCT 183 Survivors of 2004 SE Asia
tsunami with PTSD
INT 1: BWS 1SK
INT 2: BWS 1SK 1TIR
CON: 6 wk wait list
8h
Tests at
1, 6, 12, and 24 wk
INT 1 & 2 YPCL17 P<.001
YBDI P<.001
CON: no change
Franzblau et al,
34
2006
RCT 40 Women abused by intimate
partner
INT 1: testimony
INT 2: yoga breathing
INT 3: testimony 1breathing
CON: wait list
2 Sessions
45 min/session
FSES 20
INT 3 greatest
[Self-efficacy
Gordon et al,
36
2008 RCT 82 Adolescents with PTSD in
postwar Kosovo
Slow breathing, meditation,
biofeedback, movement,
guided imagery, autogenic
training, shaking, drawing,
dancing, writing
12 sessions Intervention group: YPTSD HTQ
scores
P<.001
Carter et al,
37
2010 RCT Veterans disabled with chronic
PTSD
INT: Sudarshan Kriya
CON: 6 wk wait list
5 d INT: YCAPS
Wk 6 P5.007
Wk 24 further YCAPS
CON: no change
Gerbarg et al,
35
2011 Pilot
Open
17 Adults with depression,
anxiety, PTSD related to 2001
WTC attacks
INT: BBM 2 d YBAI, BDI, ASI, all P<.001
YPSQI P<.006
YSDISL P<.004
Gerbarg et al,
35
2011 Pilot
Open
27 Adults
a
8 y after 2001 WTC attacks
GAD, panic, agoraphobia,
depression, PTSD
INT: BBM 2 d YBAI YASI YBDI
all P<.001
Brown et al
128
OBSESSIVE COMPULSIVE DISORDER
Shannahoff-Khalsa
et al,
75
1999
RCT 21 Patients with OCD INT 1: Kundalini yoga 1mantra
meditation
INT: relaxation, mindfulness
meditation
3mo
N514
INT 1 YY-BOCS
INT 2 no change
Shannahoff-Khalsa,
45
2003
Open 11 Patients with OCD Add: 12 mo Kundalini yoga 15 mo
N511
YY-BOCS
DEPRESSION
Lavey et al,
41
2005 Open 113 In-patients with MDD,
BP, dysthymia, psychosis,
borderline
INT: Hatha yoga 45 min once
a week for length of hospital
stay (average 10 d)
Tested after
yoga class
POMS Y5 negative emotions
Janakiramiah et al,
76
1998
Open 46 Adults with dysthymia INT: SKY 3 mo Subjects who practice 3 times
per wk remitted
Janakiramaiah et al,
44
2000
RCT 45 Severely depressed
hospitalized adults
INT 1: SKY 1 wk training 1
practice average 5 d per wk
INT 2: imipramine 150 mg/d
INT 3: unipolar ECT 3 times per wk
1mo YBDI, HAMD
No significant differences
between INT 1, INT 2, or INT 3
Tsang et al,
42
2006 SBRCT 82 Depressed patients
aged <65 y
INT 1: relaxation 1rhythmic
breathing 3 sessions per wk of
30–45 min
CON: newspaper discussion
3 mo INT 1 [GHQ-12 [Well-being
YDepression
[Self-efficacy
Abbreviations: ASI, Anxiety Sensitivity Index; BAI, Beck Anxiety Inventory; BBM, Breath-Body-Mind workshop; BDI, Beck Depression Inventory; BP, Bipolar; bpm,
breaths per minute; BWS, Breath Water Sound; CAPS, Clinician Administered PTSD Scale; CBT, cognitive behavioral therapy; CDISF, Children’s Depression Inven-
tory–Short Form; CES-D, Center for Epidemiological Studies Depression Scale; CHD, congestive heart failure; c/o, complain of; CON, control group; ECT, electro-
convulsive therapy; EIFI, Exercise Induced Feeling Inventory; FDI, functional disability; FSES, Franzblau Self-Efficacy Scale; F/U, follow-up; GAD, generalized
anxiety disorder; GHQ, General health Questionnaire; GI, gastrointestinal; HAM-A, Hamilton Anxiety Rating scale; HAMD, Hamilton Depression Scale; HF-HRV,
high-frequency heart rate variability; HRSD, Hamilton Depression Rating Scale; HRV, heart rate variability; HTQ, Harvard Trauma Questionnaire; IBS, Irritable Bowel
Syndrome; INT, intervention; IPAT, Institute for Personality and Ability Testing, Anxiety Scale; MABI, Maslach Burnout Inventory; MDD, Major Depressive Disorder;
MI, myocardial infarction; nrCT, nonrandomized controlled trial; OCD, obsessive-compulsive disorder; PCQ, Pain Coping Questionnaire; PCL17, Posttraumatic Stress
Disorder Check List-17; PCQ, Pain Coping Questionnaire; POMS, Profile of Mood Scale; PSQI, Pittsburg Sleep Quality Index; PSWQ, Penn State Worry Questionnaire;
PSS, Perceived Stress Scale; QOL, quality of life; RCMAS, Revised Child Manifest Anxiety Scale; SB, single blinded; SDISL, Sheehan Disability Index Social Life; SK,
Sudarshan Kriya; STAI, State-Trait Anxiety Inventory; TIR, trauma incident reduction; WTC, World Trade Center; Y-BOCS, Yale-Brown Obsessive-Compulsive Scale.
a
First responders, Ground Zero workers, health care providers, tower escapees, witnesses. Mini-mental status examination (MMSE) diagnoses: 14, generalized
anxiety disorder; 6, panic; 9, agoraphobia; 12, depression; 23, PTSD.
Mind-Body: Breathing Practices for Stress-Related Conditions 129
(slow left-nostril breathing, meditation, and postures) improved significantly on the Yale-
Brown Obsessive-Compulsive Scale compared with controls given relaxation and
mindfulness meditation.
45
Although left nostril breathing and ANB may be promising
adjunctive treatments for anxiety, efficacy in OCD requires 2 to 3 hours of daily practice.
CLINICAL CONSIDERATIONS, RISKS, AND RECOMMENDATIONS
Risks and Contraindications
Among the research studies reviewed here, no adverse reactions to mind-body prac-
tices were reported. In general, slow, gentle breath practices are safe in all psychiatric
populations. Most patients with asthma are able to benefit from yoga breathing if they
are not having acute symptoms. However, at the beginning of slow breathing, such
as coherent breathing at 4.5 to 6.5 breaths per minute, in patients with unstable
asthma, airways may tend to narrow, exacerbating respiratory problems. One author,
Dr Brown, discovered that breath moving (see earlier discussion) keeps airways open
during slow breath practices, even in patients with asthma.
46
In patients with chronic
obstructive pulmonary disease, rapid breathing can lead to air trapping with increased
carbon dioxide (CO
2
) levels.
Rapid or forceful breath practices can trigger panic attacks in anxiety disorders,
manic episodes in bipolar disorder, flashbacks in PTSD, and altered states of
consciousness or psychotic episodes in individuals with a tenuous sense of reality,
such as those with schizophrenia, borderline personality disorder, or bipolar disorder.
Rapid breath practices may be unsafe during pregnancy and in patients with cardio-
vascular disease, high blood pressure, lung disease, asthma, seizure disorder, hernia,
recent surgery, or recent myocardial infarction.
47
Hyperventilation, breathing faster or deeper than necessary, lowers serum concen-
tration of CO
2
. Novices learning breathing practices tend to exhale too forcefully,
particularly during rapid breathing, causing hypocapnia, a decline in PCO
2
, which
can lead to tingling or spasms of the hands and feet, hyperarousal, or altered mental
states. Patients with anxiety disorders, acute stress disorder, panic disorder, PTSD, or
bipolar disorder tend toward high SNS activity, low PNS activity, low baseline PCO
2
,
and greater reactivity to changes in PCO
2
. Rapid breathing, such as kapalabhati and
bhastrika (bellows breath), can increase the risk of panic attacks, flashbacks, or manic
states.
48–50
Rapid yoga breathing can increase excretion of lithium causing a drop in
serum levels. Patients who are bipolar should avoid rapid yoga breathing.
Reducing the Risks
To minimize the risks of adverse reactions, the following steps are recommended:
1. Assess patients for flashbacks, dissociative episodes, and capacity to maintain the
sense of reality. If dissociative episodes are prolonged or involve uncontrolled
switching, as in dissociative identity disorder, rapid breathing is contraindicated.
2. If there is a risk of self-injury, psychotherapy and pharmacotherapy can be
augmented with calming practices, such as coherent breathing, resistance
breathing, or ANB.
20
3. During slow breath practices, memories or re-experiencing usually are not retrau-
matizing and can facilitate trauma resolution. Discussing whatever patients expe-
rience is helpful.
4. Patients with autonomic instability or over-reactivity, such as war veterans, may
need up to 3 months of coherent breathing 20 minutes twice a day and up to 20
minutes of ANB per day to reduce the risk of overwhelming reactions before under-
taking more advanced practices.
Brown et al
130
Mind-Body Techniques in Clinical Practice
Clinician preparation
Clinicians who learn basic breath practices before introducing them into treatment are
better equipped to counsel patients regarding the choice of techniques and maintain-
ing compliance. Patients who cannot access a trainer may start with books and CDs.
However, the authors find teaching patients within therapy sessions more effective
than letting them learn it on their own.
Begin with simple, safe, effective breath practices
Coherent breathing is a simple effective introductory practice. Patients can purchase
a CD, such as Respire-1 (Coherence LLC, Pilot Point, Texas; www.coherence.com), or
a breath pacer (see “Technology-assisted breathing interventions”), follow the paced
breathing at 4.5 to 6.5 breaths per minute (bpm), and experience gentle relaxation with
no adverse effects. Prescribe 10 or 20 minutes twice a day plus additional practice as
needed.
TECHNOLOGY-ASSISTED BREATHING INTERVENTIONS
Nowhere has the merger of Eastern and Western practices been more apparent than
in the surge of technology-based programs and devices to facilitate therapeutic
breathing practices. These programs and devices include guided audio or video
tutorials, Web-based and mobile customizable breathing pacers, computer-based
and mobile physiologic monitoring, and feedback systems. This review focuses on
technology-assisted interventions that primarily support breath training with minimal
instruction in other modalities.
Background, Physiology, Systems, and Definitions
Numerous studies indicate that most people can accurately follow paced breathing
instructions with brief training
12,51
and that paced breathing using audio and video
cues can produce acute physiologic improvements and reductions in symptoms of
arousal and anxiety.
13,52,53
There are nearly 100 breath pacing applications for mobile
phones; but to the authors’ knowledge, there are no clinical trials examining their
effects on psychiatric conditions. The main drawback of these unassisted breath
pacing tools is that without clinician support, there is no feedback to guide individuals
who may need assistance in performing the breathing practices correctly. In contrast,
breath-retraining biofeedback systems offer individualized feedback using targeted
physiologic parameters (eg, respiration rate, HRV, and end-tidal CO
2
), which are either
directly related to respiration or highly correlated with changes in respiration.
Biofeedback protocols often include a respiratory strain gauge (pneumograph)
because it provides direct assessment of the respiratory rate rather than relying on
a correlated variable, such as HRV or skin temperature. This gauge obviates con-
founding factors, such as thoracic breathing (breathing into the upper chest without
expanding the lower part of the lungs) or reverse breathing (contracting the abdomen
during inhalation instead of during exhalation).
52
Although many studies treating
mental health problems include a respiratory strain gauge as a training tool, the
majority using it as a stand-alone device targeting cardiovascular disease.
52
HRV
biofeedback and respiratory feedback with capnometry (measurement of exhaled
end tidal CO
2
levels using a nasal canula) also use breath retraining as the primary
modality. HRV, based on the rate of change of the heart’s interbeat interval, is used
as a primary indicator of cardiovascular health. HRV biofeedback is typically per-
formed by sampling the real-time heart rate and displaying its natural increases during
Mind-Body: Breathing Practices for Stress-Related Conditions 131
inspiration and decreases during expiration (a phenomenon called respiratory sinus
arrhythmia) on the screen along with a Fourier transformation of the HRV data into
frequency spectrums. HRV biofeedback aims to reduce breathing frequency to
a rate unique to the individual such that real-time heart rate and respiration covary
in a perfect phase relationship, creating a sine wave heart rate pattern and a unimodal
spike in low-frequency HRV at 0.1 Hz, indicating maximal HRV and sympathovagal
balance.
54,55
This unique breathing rate between 4.5 to 6.5 bpm is called resonance
frequency.
54
Although studies using these types of devices for medical disorders
have been more rigorous, small, randomized pilots report benefits in a range of psychi-
atric disorders (Table 2).
Anxiety, Stress, Performance, Panic Disorder, PTSD, and Depression
Anxiety, stress, performance
Small pilot studies found that HRV biofeedback and respiratory strain gauge biofeed-
back can induce immediate reductions in anxiety and arousal similar to guided breath
training without devices. In 2 single-blind studies, control group participants were
instructed to use a concentrative mindfulness device while letting go of stressful
thoughts. All groups in both studies significantly reduced state anxiety and stress
levels, but changes were significantly greater in the HRV intervention compared with
the control. Moreover, the more efficient individuals were at mastering the breathing
technique, the greater the reductions in state anxiety.
56,57
Although breath retraining
reduces overall arousal and anxiety, cognitive techniques or other strategies may
also be needed, depending on the capacities of the individual.
58
Some studies in
normal populations suggest that short-term breathing-based biofeedback may yield
longer-term improvements in stress, performance anxiety, and cognitive functioning;
but more evidence is needed to validate the purported physiologic mechanisms of
long-term change.
59
In 2 studies, respiratory strain gauge biofeedback or HRV
biofeedback improved the quality of life for patients with cardiovascular disease
compared with control.
60,61
Panic disorder
Several small studies and one RCT used capnometer and strain gauge feedback to
reduce panic attacks and hyperventilation. During shallow rapid breathing, hyperven-
tilation (see earlier discussion) can lead to hypocapnia and pH imbalance (increased
blood alkalinity) with blood vessel constriction, reducing brain oxygen levels. Capn-
ometry is a prime assessment and intervention tool because rapid breathing creates
low end-tidal CO
2
, whereas slow therapeutic breathing normalizes the gas exchange.
Slow breathing and capnometry-assisted breathing relieve hypocapnia.
62
In an RCT,
capnometry-assisted respiratory training was equivalent to cognitive therapy in
reducing panic symptoms. However, capnometry-assisted training, but not cognitive
training, normalized hypocapnia, suggesting that breath retraining is a useful adjunct
to cognitive treatments in panic disorder.
63
PTSD
Individuals with PTSD have a low baseline HRV.
64
In a 4-week RCT of 38 patients with
PTSD, the HRV biofeedback group had significantly greater improvements in resting
HRV and depressive symptoms compared with a progressive muscle relaxation
group.
65
In another RCT, HRV augmentation of a trauma reduction program (TRP)
reduced PTSD scores and avoidance/numbing significantly more than TRP alone.
Increased HRV was associated with reduced PTSD scores.
66
Brown et al
132
Depression
Two small single group studies and one RCT found device-guided HRV feedback
beneficial for depression. In a 2-month RCT, HRV feedback significantly reduced
depressive symptoms versus progressive muscle relaxation.
67
In an open trial, HRV
biofeedback significantly improved fibromyalgia and depression at the 3-month
follow-up, showing potential longer-term benefits.
68
CLINICAL CONSIDERATIONS
Advantages of Technology-Assisted Breath Retraining Devices
Studies are building an evidence base for the benefits of technology-assisted thera-
peutic breathing as a stand-alone and/or adjunctive treatment of psychiatric disor-
ders. Technology-assisted breathing devices open the world of therapeutic
breathing to individuals who might not pursue traditional guided practices, such as
yoga. For example, Muench
69
reported that men are more likely than women to prefer
a portable biofeedback device to other relaxation practices. Perhaps the tangible,
gadgetlike quality is more appealing to men. Also, many find it easier to stay on
task with technology-assisted practices versus unguided breathing or meditation.
Another advantage of device-guided applications is inclusion of a history of use that
facilitates honest communication about barriers to practice, increases accountability,
and enhances compliance with homework. With the increase of continuous passive
monitoring devices, individuals will soon be able to receive notifications to practice
therapeutic breathing when changes occur in their physiology.
70–72
Limitations, Precautions, and Contraindications
Untested breathing applications using features embedded in mobile phones are flood-
ing the market. Innovative mobile phone applications include detecting respiratory
rates as the user breathes into the microphone, using the accelerometer to detect
respiratory rates by placing the phone on one’s abdomen, and using the camera as
a real-time HR sensor to display HRV. These options are intriguing, but their reliability
is questionable until validated with standard monitoring equipment.
Patient factors
Approximately 10% of people experience biofeedback-induced anxiety while
attempting (usually unsuccessfully) to alter their physiology through breathing.
57,73
Because many factors affect physiology (eg, blood pressure–regulating medications)
and some individuals are prone to dyspnea, certain assistive technologies may not be
suitable or may require additional in-person instruction.
Patient and clinician factors: cost and accessibility, ease of use
The cost of breath training programs and devices ranges from $100 to $2000 or more,
with considerable differences in their capabilities. Patients can purchase portable
devices from $100 to $300 that offer real-time feedback (usually on a single physio-
logic variable) or choose simple breath retraining phone applications that may or
may not provide feedback. It is important for clinicians to evaluate risks and benefits
for each patient and to learn how to use devices properly before recommending them.
Patients are far more likely to benefit when given some personal instruction and moni-
toring by their health care provider. For information on breath retraining devices,
protocols, and referrals, one can visit the Web sites of the Association for Applied
Psychophysiology and Biofeedback and the Quantified Self Guide to Self-Tracking
Tools.
Mind-Body: Breathing Practices for Stress-Related Conditions 133
Table 2
Clinical studies of technology-assisted breathing devices in psychiatric disorders
Study Design Subjects Method: Intervention/Controls Length Outcome
a
Anxiety/Stress (Ib efficiacy)
Morarend
et al,
58
2011
RCT 81 Patients with
dental anxiety
INT: respiratory strain gauge
device (ambulatory)
CON: no treatment
15 min INT: YVAS negative feelings about
dental injection; no change CSAS, DISS
CON: no change
Sherlin et al,
56,57
2009, 2010
RCT (SB) 43 Individuals
with high levels of
perceived stress
INT 1: HRV biofeedback device
(ambulatory)
ACON: passive concentrative control
device (ambulatory)
15 min INT 1 >ACON:
YSTAI-S, YHR &
[alpha waves in anterior
cingulated cortex
Sutarto et al,
2010
Pilot study 9 Female university
students
INT: 6 sessions of HRV biofeedback (office
based 1home practice)
ACON: no treatment
3 wk INT: [verbal memory & mathematical
decision making
CON: no changes
Prinsaloo et al,
2011
RCT (SB) 18 Individuals reporting
high perceived stress
INT 1: HRV biofeedback device
(ambulatory)
ACON: passive concentrative device
(ambulatory)
15 min INT >ACON: [subjective feelings of
relaxation (SRI); [scores cognitive
task (MST)
INT 1 & ACON: YSTAI-S; [SRI
Lemaire et al,
2011
RCT 40 Physicians INT: social support 1HRV biofeedback
CON: social support visits only
28 d INT >CON: Yglobal perceptions of
work-related stress
Ratanasiripong
et al, 2012
RCT 60 Nursing students INT: HRV biofeedback device
(ambulatory)
CON: no treatment
5 wk INT: YSTAI-S & PSS
CON: no changes
Meuret et al,
63
2009, 2010
RCT 41 Patients with
panic disorder
INT 1: capnometry-assisted respiratory
training
INT 2: cognitive therapy
5 wk INT 1 & INT 2: YPDSS; YACQ; YSTAI
INT 1 >INT 2:
Yhypocapnic breathing
Brown et al
134
PTSD (IIa efficacy)
Zucker et al,
65
2009
RCT 38 Individuals in drug
treatment with
elevated PTSD scores
INT 1: HRV biofeedback device
(ambulatory)
INT 2: progressive muscle relaxation
audio training
4 wk INT 1 >INT 2: YBDI; [HRV
INT 1 & INT 2: YPCL; YISI
Tan et al, 2010 RCT 20 Veterans with PTSD INT 1: TRP 18 office-based HRV
biofeedback sessions 1home practice
TAU CON: TRP only
8 wk INT >CON: YPCL avoidance & numbing
subscale
INT 1 & TAU CON: YPCL
Depression (Ib efficacy)
Karavidas et al,
2007
Pilot study 11 Individuals with MDD Single pilot group: office-based HRV
biofeedback 1home practice
10 sessions INT YBDI & HAM-D; [HRV
Seipmann et al,
2008
Pilot study 14 Patients with varying
degrees of depression
12 Healthy adults
6 Office-based HRV biofeedback
sessions 1home practice
2 wk Depressed group: YBDI; YSTAI; [HRV
Healthy group: no changes
Rene,
67
2008 RCT 32 Women enrolled in
welfare-to-work
program
INT 1: HRV biofeedback device
(ambulatory)
INT 2: daily progressive muscle relaxation
audio training
8 wk INT 1 >INT 2: YBDI; [employment and
motivation
INT 1 & INT 2: YISI
Hasset et al,
68
2007
Pilot study 12 Women with
fibromyalgia
10 Weekly sessions of HRV
Biofeedback
12 wk INT YBDI & MPQ; [overall functioning
Abbreviations: ACON, active control group; ACQ, Anxiety Control Questionnaire; ASI, Anxiety Sensitivity Index; BAI, Beck Anxiety inventory; CDAS, Corah Dental
Anxiety Scale; CON, control group; DISS, Dental Injection Sensitivity Survey (Krochak and Friedman, 1998); HAM-D1, Hamilton Depression Rating scale; HRV: heart
rate variability; INT: intervention; INT 1: main Intervention; INT 2: Alternate Intervention; INT 1 > INT 2, significantly greater change in INT 1 compared with INT 2;
INT 1 & INT 2: significant changes within groups but not between groups ambulatory: device used at home; IIa efficacy: evidence from at least one well-performed
study with control group; Ib efficacy: evidence from at least one randomized study with control; MPQ: McGill Pain Questionnaire; PDSS: Panic Disorder Sensitivity
Scale; SB, single blinded; SRI, Smith Relaxation Inventory; STAI: State-Trait Anxiety Inventory; TAU: treatment as usual; TRP, trauma reduction program; UP, unpub-
lished; VAS: visual analog scale.
a
NOTE: All findings presented are statistically significant.
Mind-Body: Breathing Practices for Stress-Related Conditions 135
SUMMARY
The empiric literature on therapeutic breathing for psychiatric disorders is expanding
along with the breath retraining technologies. Clinicians interested in integrating breath
practices into their work will be able to choose applications that they find most suitable
to their patient population and to their own practice style. As with other treatment deci-
sions, the choice of technology should take into consideration the evidence of efficacy,
reliability, cost, ease of use, interests of the clinician, patient preferences, patient moti-
vation, risk factors, and capacities to learn these new techniques.
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