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| Journal of the New Zealand Medical Association,
12-December-2003, Vol 116 No 1187
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Buteyko Breathing Technique for asthma: an effective
intervention
Patrick McHugh, Fergus Aitcheson, Bruce Duncan and Frank
Houghton
Asthma is a common disorder in New Zealand, with estimates
of prevalence as high as one in six of the
population.1 The annual cost of asthma drugs is
high, with approximately $30 million spent in 2002 on inhaled corticosteroids
and
β2-agonists.2
Any intervention that reduces drug utilisation could have a major impact on
pharmaceutical expenditure.2
Complementary and alternative therapies (CATs) are widely
used by patients with chronic illnesses. CAT use amongst patients with asthma
appears particularly high, with rates of up to 42% reported in some
populations.3 The range of CATs employed is
wide; however, CAT research in asthma is characterised by a lack of adequately
sized randomised controlled trials.4
The Buteyko Breathing Technique (BBT) is a CAT used by
asthma patients that has enjoyed increasing popularity over recent years. One
small, randomised controlled trial of the BBT showed marked reduction in asthma
drug consumption among patients in Brisbane,
Australia.5 A further trial, based on the use
of a BBT video has also demonstrated BBT is effective in reducing
β2-agonist
use.6
We report a study that investigates the efficacy of BBT in a
selected group of New Zealand patients.
MethodsStudy
participants General practitioners (GPs) were approached to send out a
letter to practice patients with a diagnosis of asthma inviting them to
participate in the study. A brief phone interview was conducted, following which
respondents were then booked for a pre-run-in interview where
appropriate.
Respondents were eligible for inclusion if they were
between 18 and 70 years old, previously diagnosed with asthma by their GP, and
using moderate to high doses of medication for asthma. For the purposes of this
study, asthma was defined as a history of variable difficulty in breathing with
wheeze or chest tightness, and improvement after the use of a
β2-agonist.
A ‘moderate to high’ dose was defined as at least 1400 mcg of
short-acting
β2-agonist
weekly (or equivalent long-acting
β2-agonist)
and/or significant use of inhaled steroid medication (1400 mcg of beclomethasone
or equivalent per week). This was measured over the last week of the run-in
period. Dose equivalence was calculated as follows: 100 mcg of salbutamol = 25
mcg of salmeterol, and 100 mcg of beclomethasone = 100 mcg budesonide = 50 mcg
of fluticasone6.
Respondents were ineligible if they had experienced a
change in inhaled steroid dose or used oral steroids during the four-week run-in
period. Prior instruction in BBT or a significant unstable medical condition
were also exclusion criteria.
Sample size calculation was based around the observed
differences in medication use in the Brisbane
study.5 This indicated a requirement for
approximately 20 participants in each group to demonstrate a statistically
significant reduction in medication dosage, at a 95% confidence interval (CI)
and 80% power to demonstrate such a difference.
The study had received prior approval by the Tairawhiti
Regional Ethics Committee. Informed consent was obtained for all
participants.
Intervention
Participants were paired on the basis of severity of asthma. They were then
randomised to either Buteyko or control group using a computer-generated list.
Trial participants were blinded as to whether they had been assigned to the
treatment or control group. Investigators involved in pulmonary function testing
and other outcome assessments were blinded as to treatment assignment as were
investigators who contacted participants during the study to advise re drug
dosing.
Trial participants underwent training simultaneously in
two separate groups. Teaching occurred over seven days with each session lasting
60–90 minutes. Participants were informed the trial involved two different
forms of asthma education, both of which were thought to be useful in reducing
reliance on medication and improving control of asthma.
A representative of the Buteyko Institute of Breathing
and Health (BIBH), following their usual teaching practices, taught the BBT. BBT
consisted of a series of exercises promoting hypoventilation. Control training
consisted of general asthma education and relaxation techniques, as currently
used by Gisborne Hospital.
The tutors contacted participants in both groups one
week after conclusion of the final teaching session. Participants were
instructed to contact their tutor thereafter whenever they wished. If contact
occurred, the matched participant in the other treatment group was telephoned by
their tutor to control for frequency of contact.
Outcome
measures Over a four-week run-in period participants completed a diary
card recording symptom scores (0 = no symptoms, 3 = maximal symptoms) and daily
use of asthma medication. Four-week diary cards were also completed prior to the
six-week, three-month and six-month assessments. Baseline spirometry was
performed at the end of the run-in period and repeated at the three-month and
six-month assessments.
Participants were seen for review six weeks into the
trial. Medication use was reviewed and where appropriate advice was given to
adjust dosages. At every contact, participants were reminded to use
β2-agonist
only when symptomatic. After the six-week review, all participants were
contacted where possible by phone every three weeks, medication reviewed and
appropriate advice given. Dosage reduction protocol described in the Brisbane
trial was utilised.5
ResultsParticipants
Nineteen GPs agreed to send out letters to patients with asthma registered with
their practices. There were 64 respondents to the letter of which 51 met initial
inclusion criteria. Subsequent to a face-to-face interview, two were excluded
due to having unstable medical conditions, six were excluded for insufficient
medication/treatment use during run-in and five were excluded after using oral
steroids during run-in. After the run-in period, 38 participants were allocated
equally between each group. Four withdrew after allocation and prior to
completion of the teaching, leaving 34 available for evaluation.
Demographic characteristics, smoking status, medication use,
asthma symptom score and asthma severity at baseline are indicated in Table 1.
There were no significant differences between the BBT group and the control
group on the basis of age, asthma symptom score,
β2-agonist
dose or inhaled steroid dose. The BBT group had a significantly lower
percentage predicted FEV1 at end of run-in (p =
0.038).
Table 1. Characteristics of participants at end of
run-in period
β2-agonist
use Figure 1 illustrates
β2-agonist
use by group.
Figure
1. β2-agonist use by group (with 95% CI)
 At baseline, there was no significant difference in mean
β2-agonist
use between BBT and control. At six weeks, both groups showed significant
reduction in
β2-agonist
usage from baseline (BBT p = 0.001; control p = 0.020). The reduction in
usage in the BBT group was greater than that in the control at six weeks (BBT
94% reduction, control 56% reduction, p = 0.001) and three months (BBT 86%
reduction, control 51% reduction, p = 0.007); however, by six months the
difference was no longer statistically significant (BBT 85% reduction, control
37% reduction, p = 0.102).
Inhaled steroid use
Figure 2 illustrates inhaled steroid use for the two groups.
Figure 2. Inhaled steroid use by group (with 95%
CI)
 Mean inhaled steroid use was the same at baseline for both
groups. At six weeks (BBT 34% reduction, control 10% increase, p = 0.032), three
months (BBT 36% reduction, control 2% increase, p = 0.011) and six months (BBT
50% reduction, control 1% increase, p = 0.003), there was a significant
reduction in inhaled steroid use in the BBT group that was not observed in the
control group.
Percentage predicted
FEV1 Percentage predicted
FEV1 for both groups is illustrated in Figure
3.
Percentage predicted FEV1 was
statistically significantly lower in the BBT group at end of run-in. This
difference became non-significant at three months and six months. There was no
significant change in percentage predicted FEV1
in either group during the study.
Figure 3. Percentage predicted
FEV1 by group (with 95% CI)
 Adverse events There
were no admissions to hospital or attendances at ED for any participants in the
trial during the trial or during the 12-month period following completion of the
study. Three control and two BBT subjects received short courses of prednisone
during the six months of the post-instruction trial period.
Phone contacts The
instructor contacted all participants once one week after completion of the
intervention. After completion of instruction, only three patient-initiated
contacts were recorded; two from BBT group participants and one from a control
group participant. On these occasions, the matched-pair partner of the
participant was contacted by their instructor. Phone contacts between
participants and their respective tutors and between participants and the
investigators were the same for the BBT and the control groups.
DiscussionThis study broadly replicates the
findings of Bowler et al.5 BBT as taught by a
member of BIBH was observed to produce a large clinically significant reduction
in β2-agonist
and inhaled steroid use without negative impact on measures of lung
function and with no apparent adverse effects.
The study by Bowler et al demonstrated inhaled steroid
reduction of 49% for the BBT group and 0% for the control group at three
months.5 The current study exhibited inhaled
steroid reduction of 50% in the BBT group and a 1% increase for the control
group at six months.
With regards
β2-agonist
use, Bowler et al demonstrated a 95% reduction in the BBT group and a 7%
reduction in the control group at three months. Our study showed a reduction of
85% in the BBT group and a reduction of 37% in the control group at six months.
The magnitude of effect in both studies was remarkably similar.
The experimental design of this trial controlled for the
inequality of investigator contact, which was criticised in commentary on the
Brisbane trial.7,8 In the current trial
post-intervention phone contact in both BBT and control group by the tutor was
minimal and equal. The similarity in results between the two trials suggests
that factors other than contact bias were operating to produce the observed
results. It is noteworthy that the dose reductions observed in this
investigation were durable, persisting up to six months post-intervention. This
represents the longest follow up yet reported of a BBT intervention.
There is no universally accepted diagnostic criterion for
the diagnosis of asthma.9 Therefore patients
with a GP-assigned diagnosis of asthma with a confirmed background of variable
difficulty in breathing and symptomatic relief following
β2-agonist
use were chosen, as they form a valid and relevant study
population.10 Within this group of patients
there may be considerable heterogeneity, including patients whose primary
problem may be dysfunctional
breathing.11
Although investigators were blinded to treatment assignment,
the use of the term Buteyko was allowed with participants assigned to that
group. This is in contrast to the practice of Bowler et al, although in that
study participants were aware at recruitment that the trial was a trial of
BBT.5 It was considered that use of the term
would not unduly bias results, and was preferable to unrealistic efforts to
maintain complete blinding.
The ability to produce marked reductions in asthma-drug
utilisation suggests that the pharmaco-economic implications of BBT merit
further study. Clarification of the mechanism(s) underlying the effectiveness of
BBT is a further goal,12 given that BBT appears
to represent a safe, efficacious alternative for the management of
asthma.
Author information:
Patrick McHugh, Clinical Director, Emergency Department, Gisborne
Hospital; Fergus Aitcheson, Consultant Physician, Gisborne Hospital; Bruce
Duncan, Medical Director, Tairawhiti District Health, New Zealand; Frank
Houghton, Health Geographer, Department of Public Health, Mid-Western Health
Board, Limerick, Ireland
Acknowledgements:
This study was funded by grants from White Cross Group and the Tairawhiti
Therapeutics and Arts Trust. Thanks to Glenn Smith for teaching the control
group, BIBH for providing an instructor (Russell Stark) for teaching the BBT
group, the GPs and practice nurses who participated, and also to Liz Buckley and
Graham Gomm for their assistance.
Correspondence: Dr
Patrick McHugh, Emergency Department, Gisborne Hospital, Private Bag 7001,
Gisborne. Fax: (06) 869 0522; email: mchugh@tdh.org.nz
References:
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