Didgeridoo playing as alternative treatment for obstructive sleep apnoea syndrome: randomised controlled trial
BMJ 2006; 332 doi: https://doi.org/10.1136/bmj.38705.470590.55 (Published 02 February 2006) Cite this as: BMJ 2006;332:266All rapid responses
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I'd be interested to know if you did any more studies in this direction
Competing interests: No competing interests
That the tuba player has mild apnea is not evidence that tuba does
not have a positive effect. He might have had moderate apnea instead (or
none at all--the effect doesn't have to be positive!) in the absence of
tuba playing. In fact, tuba playing could have a bigger effect on apnea
than didgeridoo playing; it's not been tested. We clearly need studies
confirming the didgeridoo effect and follow-on studies that determine why
it works, assuming that it does.
Competing interests:
None declared
Competing interests: No competing interests
http://aboriginalart.com.au/didgeridoo/dig_background.html
The above website provides both listening and learning instructions
on didgeridoo playing. Other related websites refer to the abilty of
the instrument to influence vagal involvement. An online search for
'digeridoo vagus' will provide a wide range of associated information in
that regard.
In my first response, I stated that a theoretical model of sleep and
arousal which I have constructed, suggests that
the low Hz. vibrations of the didgeridoo are conducted downward along the
efferent vagal pathway, and in common with the Pasche spoon, the OMMMM
utterances and the 'Tibetan stomach singing', they result in reduction of
abdominal afferential vagal signalling back to the nucleus tractus
solitarius (NTS) in the brainstem.The overall result is that SNS input is
decreased, and in the case of insomnia this facilitates sleep onset.
Now may be the appropriate time to provide additional and more
detailed information in that regard. The following has been copied
directly from the relevant section of the model's text:
Research conducted by Hawthorn et al (1988) on the ferret showed that
electrical stimulation of the abdominal afferent vagus nerve caused the
release of increased levels of vasopressin (AVP) but not oxytocin (OT) in
the NTS. Independent of their individual roles peripherally, central
involvement of both AVP and OT as regulatory neurotransmitters of the
autonomic system was clearly demonstrated by Landgraf et al.(1990) using
anaesthetized rats. Electrical stimulation of the ipsilateral
paraventricular nucleus (PVN) of the hypothalamus, resulted in a 5-fold
increased level of OT and AVP, recovered and measured in a push-pull
perfusate of the NTS and dorsal motor vagus (DMV) area. After stimulation,
the peptides were found to return to the level of controls. An osmotic
stimulus failed to increase AVP and OT levels in the NTS/DMV perfusate.
The authors concluded that their results were consistent with the view
that both peptides are centrally involved as neurotransmitters in
autonomic regulation.
Central oxytocinergic neurons had also been hypothesized to influence
gastric motility and secretion by increasing the excitability of central
vagal neurons in the NTS and the nucleus of the DMV. Support for this
hypothesis was evidenced in a study using the rat by McCann and Rogers
(1990). In the following year Nordmann and Steunkel (1991) demonstrated
that Na+ acts directly in releasing AVP from rat isolated neurohypophysial
nerve endings. The secretory elevation was dose dependently related to Na+
and could occur in the absence of Ca++. The authors concluded that Na+ per
se may be an intrinsic regulator of basal neurosecretion.
A study by Raggenbass et al. (1992) carried the work forward by
elucidating the roles played by both Na+ and Ca++ in the regulation of
vagal neurotransmission in the brainstem. These investigators studied the
effect of OT on brainstem slices of vagal neurons of the rat. OT induced
current was concluded to be inward and voltage dependent since its
magnitude moved from the resting potential toward less negative
potentials. Regulation of the OT induced current in response to membrane
potential suggested that OT acts by effecting opening of voltage dependent
channels, which can exist in either of two states ...open or closed.
Extracelluar calcium (Ca++) in lowered concentration enhanced the OT
response, while raising the Ca++ concentration reduced it. Partial
replacement of ECF Na+ was shown to reversibly attenuate or suppress the
OT current. The authors concluded that OT increases the excitability of
vagal neurons by generating a voltage-gated current, which is modulated by
divalent cations and carried by Na+.
More recently, a paper dealing with peptides as neurotransmitters in
vascular autonomic neurons (Morris,1995) stated that neuropeptides are
present in the majority of autonomic neurons projecting to blood vessels,
where they work in conjunction with non- peptide transmitters and
sometimes with other peptides in regularly producing potent effects on
vascular tone, which often are restricted to selected regions in the
vasculature. Neuropeptides can thus be regarded also as being important
contributors to the regional regulation of the vasculature in selectively
responding to various physiological stimuli.
From the foregoing it is hypothesized that an increasing
concentration of Na+ perfusing the abdominal afferent collaterals of the
vagus nerve in humans would likewise produce current and stimulate the
release of AVP but not OT in the NTS, in a manner analogous to that
demonstrated by Hawthorn et al.(1988) in the ferret. This in turn should
lead to a corresponding lowering of OT voltage-gating current, a reduction
in membrane permeability and lessening of the excitability of efferent
vagal neurons, as was described by Raggenbass et al.(1992) in the rat-
tissue demonstration in vitro, thus leading to a reduction in
parasympathetic activity.
Hence , by combining the outcomes of these two studies, it becomes
possible to suggest how the regulation of parasympathetic outflow from the
brainstem along the efferent vagal pathway can be directly influenced by
the effects of a concentration dependent sodium carried current acting
along the abdominal afferent vagus nerve.
References
Hawthorn J, Andrews PL, Ang VT, Jenkins JS. (1988) Differential
release of vasopressin and oxytocin in response to abdominal vagal
afferent
stimulation or apomorphine in the ferret. Brain Research (Netherlands)
1988 (Jan 12); 438(1-2):193-8
Nordmann JJ, Steunkel EL. (1991) Ca++ independent regulation of
neurosecretion by intracelluar Na+.
FEBS Letters; 292: 1,2: 37-41
Raggenbasss M, Dreifuss J J. (1992) Mechanism of action of oxytocin
in ratvagal neurons:
induction of a sustained sodium-dependent current. J.Physiology (London,
England), 457: Nov. 1992, 131-42
Morris JL. (1995) Peptides as neurotransmitters in vascular autonomic
neurons.
Clinical Experimental Pharmacology and Physiology 1995 (Nov);22:.792-802
Competing interests:
None declared
Competing interests: No competing interests
This study is of great interest, especially given the lack of alternatives to CPAP. As correctly pointed out by the authors, given CPAP's lack of appeal, "[o]ne of the challenges in the treatment of sleep disorders is poor compliance". In neuropsychiatry, the human cost of disrupted sleep in terms of potentially reversible cognitive deficits and disordered mood (primarily depression, but also elevation) is staggering. Epileptic patients with OSA may become intractable just because of disrupted sleep.
All caveats to this innovative approach mentioned in prior comments certainly apply: Need for replication, sample bias etc. Also, waitlisting is problematic as a control [corrected from "not a bad control" on 14 March] in a syndrome that fluctuates over time, such as mild-moderate sleep apnea.
Given the realities of medicine at least in the U.S., well-designed large scale studies are unlikely to surface as there is no monetary incentive.
The last comment from Patrick J. Votrian, the Dutch tuba player is interesting in that it seems to stress the central role of circular breathing in upper airway retraining. This should not be too difficult to test in an experimental model. Also, unlike tuba players, clarinetists use circular breathing (a technique that takes many months to master). What is the prevalence of UERS/OSA in clarinet players?
Maurice Preter, M.D.
Psychiatry and Neurology
Assistant Professor of Clinical Psychiatry,
Columbia University College of Physicians & Surgeons,
1160 Fifth Avenue, Suite 112, NY, NY 10029,
www.psychiatryneurology.com
Competing interests:
None declared
Competing interests: No competing interests
and now for a word from the battle front...
I am a professional tuba player of 43yrs and have played the tuba
since the
age of 12 (also known as bass tuba or contrabass tuba).
I have a light form of Apnoea and have been under
observation/treatment
since 2002 via the Sloterdijk Hospital (Ziekenhuis) in Amsterdam, the
Netherlands.
My response is more of 2 questions.
1.If the pure low vibrations of didgeridoo playing are assisting in
the
reduction of Apnoea symptoms, than why isn't the same affect achieved by
playing the tuba?
2.If the pure physical playing of a didgeridoo reduces Apnoea
symptoms,
than how does it differ from that of playing the tuba? The usage of the
circular breathing technique on the didgeridoo is the only difference
between
the two playing techniques that I am aware of.
(circular breathing involves filling the cheeks with air from the
lungs, then
expelling this air by contracting the cheeks. At the precise moment of
check
contraction a second action is performed of filling the lungs with air
through
the nose. In this way, a continuous stream of air is pressed through the
lips,
allowing them to continually vibrate thus producing a continuous sound.
Generally speaking, a tuba is mostly played by simply filling the lungs
with
air, expelling that air directly, and stopping the sound production to
fill the
lungs once again with air.)
Competing interests:
None declared
Competing interests: No competing interests
Low Energy Emission Therapy (LEET) was a term employed by Dr.
Boris Pasche in describing his invention of a spoon-like radio-wave
transmitter, which he designed to treat insomnia.(Interested readers
should visit
http://www.personalmd.com/news/a1997043004.shtml for further
information.)
In anticipation of sleep, the spoon is hooked up to a small bedside
transmitter, and is understood to be emitting low -level radio frequencies
into the brain via the roof of the mouth . Tests conducted at both the
Scripps Institute in California, and at Denver's University of Colorado
Health Sciences Center, concluded that troubled sleepers who were using
the LEET device, fell asleep 18 minutes earlier than those using a 'sham'
device.
While the device was deemed effective in treating insomnia in some
circumstances, the big mystery remained as to how low-leve(Hz)
frequencies could possibly help in inducing sleep.
Based on a theoretical model of sleep and arousal which I have
constructed I would propose that the assumption that LEET activity is
signalled DIRECTLY into the brain, is incorrect. Instead, application of
the model would imply that the LEET stimulates the downward efferent
pathway of the pharyngeal vagus; and in a manner comparable to the low
Hz. intonations of Bhuddist monks when they employ their deep sounding
OMMMMM utterances during mediation... and beyond that to even lower Hz.
vibratory accomplishments via attaining the ability to perform what is
described as 'Tibetan stomach-singing'.
Likewise, I submit,the low Hz. vibrations of the diggeridoo are
conducted downward along the efferent vagal pathway, and in common with
the Pasche spoon, the OMMMM utterances and the 'Tibetan stomach
singing', they result in reduction of abdominal afferential vagal
signalling back to the nucleus tractus solitarius (NTS) in the
brainstem.The overall result is that SNS input is decreased, and in the
case of insomnia this facilitates sleep onset.
The model supports the conclusions of the authors, but inasmuch as
the foregoing may be relevant, it is suggested that it may merit
consideration.
Edward J.O'Hagan,
Niagara Falls,
Canada
Competing interests:
None declared
Competing interests: No competing interests
I congratulate Puhan and colleagues for their interesting study on a
novel treatment for obstructive sleep apnoea (OSA)1. At first glance, the
study appears to have good internal validity and is persuasive. However,
closer inspection reveals that the evidence is weak for the following
reasons.
Puhan selected non-obese participants (average BMI 25.8) with
moderate OSA. The outcomes can be divided into subjective and objective
measures. The Epworth sleepiness score is a subjective measure and showed
the strongest positive effect in the trial. Those who use the Epworth
regularly recognise that the score is dependent on many factors. Despite
the title “randomised controlled trial”, this is not a “placebo
controlled” trial. As acknowledged by the authors, the participants in the
Didgeridoo arm were highly motivated and it would be surprising indeed if
the Epworth did not show a strong placebo effect.
The Apnoea Hypopnea Index (AHI) is an ‘objective’ outcome measure.
However the AHI is an imperfect measure of OSA severity. The halving of
AHI from 22.3 to 11.6 at 4 months may seem impressive. However Puhan’s
paper doesn’t give enough details on whether this change is due to change
in weight or night to night variability caused by differences in sleep
stages, amount of supine versus non-supine sleep, prior sleep deprivation,
degree of nasal congestion, prior alcohol use, biological variability and
inter/ intra-scorer variability in marking apnoeas and hypopnoeas2.
The study is very small size and some readers may misinterpret the p
value of 0.05 for change in AHI as indicating that there is only 5%
probability of the observed results being a chance finding. This is not
so. The p value gives a falsely exaggerated impression that the ‘data
speaks for itself’3.
Using a Bayesian approach4: As there are no previous studies showing
that upper airway muscle training would improve OSA, it is reasonable to
assume a 90% pre-trial probability that the null hypothesis is correct
(i.e. that Didgeridoo playing is no better than placebo). A p value of
0.05 approximates a Bayes Factor of 0.15. This gives a post-trial
probability that the null hypothesis being correct as 57.4%. i.e. it is
still more likely that the null hypothesis is correct. This highlights the
importance of using the totality of evidence from other trials when
interpreting p values in single trials5.
The burden of OSA in the community is large and many patients
tolerate continuous positive airway pressure poorly. New approaches to
treatment are necessary. However, the data in this trial is unconvincing
that the Didgeridoo will emerge as a useful therapy, especially in those
with obesity and more severe disease.
REF:
1. Puhan MA, Suarez A, Cascio CL, Zahn A, Heitz M, Braendli O. Didgeridoo
playing as alternative treatment for obstructive sleep apnoea syndrome:
randomised controlled trial. BMJ, doi:10.1136/bmj.38705.470590.55
(published 23 December 2005)
2. Le Bon O, Hoffmann G, Tecco J, Staner L, Noseda A, Pelc I,
Linkowski P. Mild to moderate sleep respiratory events: one negative night
may not be enough. CHEST 2000; 118: 353–359.
3. Goodman SN. Toward evidence-based medical statistics. 1: The p
value fallacy. Ann Intern Med. 1999;130:995-1004.
4. Goodman SN. Toward evidence-based medical statistics. 2: The Bayes
Factor. Ann Intern Med. 1999;130:1005-1013.
5. Lilford RJ, Braunholtz D. The statistical basis of public policy:
a paradigm shift is overdue. BMJ 1996;313:603-607
Competing interests:
None declared
Competing interests: No competing interests
On Psychoacoustic Studies of Didgeridoo
Introduction:
The recent Ig Nobel Prize (2017) has been awarded to a pioneering study conducted by Puhan and Colleagues in 2006; because of its potential implications for health.1,2 The Ig Nobel Prizes are in general introduced with a motivation to encourage research studies that initially make you laugh, but later leave you thinking.1 In the above-mentioned study,2 which was published in the British Medical Journal (BMJ), they showed for the first time, how the regular practice and playing of didgeridoo can help in reducing the problems caused by Obstructive Sleep Apnea (OSA). Since OSA is a potentially serious disorder, studies concerned with alternative ways of preventing and healing can be of great value. Thus, it is no surprise that this study has won the Ig Nobel Prize award. This is the first study to exploit didgeridoo – the oldest wind instrument that belongs to Australian Aboriginal tribes,3 - for its health and healing benefits. Though this study has triggered many similar studies that use this instrument for varying purposes,4 we still haven’t explored its entire potential for different health conditions. In light of the latest achievement,1 here, we discuss the other possible uses of the didgeridoo, and also the kind of studies that are needed to explore its benefits. Such ideas are helpful in expanding the work of Puhan et al. (2006), and the outcomes may supplement and support various medical interventions.
The Psychoacoustic Studies of Didgeridoo:
In Puhan et al. (2006), and other studies that followed, the main focus has been on how the practice of playing didgeridoo can help in preventing a few health issues.2,4 They usually connect most of these benefits to a unique blowing technique (called circular breathing technique) by which one plays this instrument. According to the latest survey, since adherence to commonly available treatments like Continuous Positive Airway Pressure (CPAP) is low, number of patients are interested in didgeridoo as an alternative therapy for OSA.5 Though we have numerous studies reporting the benefits of playing the didgeridoo, it is surprising that we lack large-scale statistical studies of the effects of didgeridoo in subjects with different backgrounds and health conditions.4,5 Thus, there is a need for attention of the mainstream community to take these issues into consideration. Even in that case, this kind of studies can only reveal how an individual (either a player or practitioner) benefits from blowing the instrument. In addition to this, if we are interested in investigating the extent to which a playing instrument would influence/affect the (passive) listener or audience, a different section of research studies (analyzing the psychoacoustics) are needed. The latter studies may aid in knowing how listening to such an instrument may benefit in cultivating the health and well being. Thus, any investigation exploring the potential use of an instrument would be complete only with the combination of the former and latter set of studies.
Apart from this, the other ways and purposes of studying the instrument may also result from one’s knowledge of the respective tradition; as, to why and in what context, do the aboriginals use didgeridoo? Do they use it simply as a musical instrument? Or is there any other known practice? In this context, if we explore the traditional usage of the didgeridoo, we find to our surprise that aboriginals use it primarily for healing and wellbeing, and also during spiritual retreats, ritualistic practices and special ceremonies.3 This is because they believe that frequencies/sounds emanated from didgeridoo have healing components. Empirically, such notions can be verified only through the psychoacoustic studies of the didgeridoo. Since we already have a few psychoacoustic studies (of different instruments) showing the influence of specific sounds/frequencies (and even music) on one’s mind and emotions,6-8 it is important to conduct such studies on didgeridoo as well.
In this connection, preliminary evidence of the benefits/positive effects of didgeridoo sounds can be drawn from the acoustic studies conducted on didgeridoo.9,10 Here, they studied the blowing acoustics and also analyzed the sound spectrum radiated from playing didgeridoo in different scenarios. On thorough examination of radiated sound spectra of these cases, one can notice the presence of sound components in the infrasonic range as well as in ultrasonic range; which in turn depends on various other factors. Since both infrasound frequencies and ultrasound frequencies (of low-to-mid range) are known to have beneficial effects on biological systems, one may relate this directly to the healing properties of didgeridoo sounds. For an in-depth understanding of how these frequencies may affect, one needs to examine the mechanisms by which they trigger various biophysical processes (to know the physiological influence), and neurophysiological processes in connection to psychoacoustics. In the context of therapeutic and healing applications, several studies have already identified and categorized some of the possible effects based on the nature of mechanisms they produce in the body. 6-8
Conclusion:
In this respect, the present letter is an attempt to suggest that the infrasonic and ultrasonic frequency components present in the sound emanated by the didgeridoo may be beneficial in other health conditions. Such findings may support alternative ways of healing such as sound healing and music therapy and thereby complement other clinical interventions. It also brings to the notice of mainstream research community that there is a need for large-scale studies on exploiting didgeridoo as an alternative therapy.
Competing interests: No competing interests
Correspondence to: J. Shashi Kiran Reddy – jumpal_shashi@yahoo.com, jumpalreddy@live.com
References:
1. Tanne JH. BMJ papers on ear growth and didgeridoo for sleep apnea win Ig Nobel awards. BMJ 2017; 358: j4303 doi: 10.1136/bmj.j4303
2. Puhan MA, Suarez A, Lo Cascio C, Zahn A, Heitz M, Braendli O. Didgeridoo playing as alternative treatment for obstructive sleep apnoea syndrome: randomised controlled trial. BMJ 2006; 358: 266-70. doi:10.1136/bmj.38705.470590.55. pmid:16377643.
3. Schellberg D. Didgeridoo: Ritual Origins and Playing Techniques. Red Wheel/Weiser Publisher 1996.
4. Eley R, Gorman D. Didgeridoo playing and singing to support asthma management in Aboriginal Australians. The Journal of Rural Health 2010; 26(1): 100-104
5. Petro A, Dzierzewski JM, Martin JL, Alessi C, Jouldjian S, Josephson K, Suarez A, Fung C. 0573 A Survey To Assess Patients’ Interest In the Didgeridoo as an Alternative Therapy for Obstructive Sleep Apnea. Sleep 2017; 40: Pages A213 (Issue Suppl_1). https://doi.org/10.1093/sleepj/zsx050.572.
6. Juslin PN (Ed), Sloboda JA (Ed). Music and Emotion: Theory and Research (Series in Affective Science) 1st Edition. Oxford University Press 2001.
7. Suseela YV, Reddy JSK. A note on possible healing effects of Conch Shell frequencies.
NeuroQuantology 2017; 15 (3): 193-196.
8. O'Brien Jr. WD. Ultrasound-biophysics mechanisms. Prog Biophys Mol Biol. 2007; 93(1-3): 212-255. doi: 10.1016/j.pbiomolbio.2006.07.010
9. Amir N. Some insights into the acoustics of the Didjeridu. Applied Acoustics 2004; 65: 1181-1196.
10. Tarnopolsky AZ, Fletcher NH, Hollenberg LCL, Lange BD, Smith J, Wolfe J. Vocal tract resonances and the sound of the Australian didjeridu yidaki I. Experiment. J. Acoust. Soc. Am. 2006; 119: 1194-1204.
Competing interests: No competing interests