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The influence of head-of-bed elevation in patients with obstructive sleep apnea

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  • Heart Institute, University of São Paulo
Article

The influence of head-of-bed elevation in patients with obstructive sleep apnea

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Purpose: The purpose of this study is to test the effects of a mild degree of head-of-bed elevation (HOBE) (7.5°) on obstructive sleep apnea (OSA) severity and sleep quality. Methods: OSA patients were recruited from a single sleep clinic (Criciúma, Santa Catarina, Brazil). Following a baseline polysomnography (PSG), all patients underwent a PSG with HOBE (within 2 weeks). In addition, a subset of patients performed a third PSG without HOBE. Results: Fifty-two patients were included in the study (age 53.2 ± 9.1 years; BMI 29.6 ± 4.8 kg/m(2), neck circumference 38.9 ± 3.8 cm, and Epworth Sleepiness Scale 15 ± 7). Compared to baseline, HOBE significantly decreased the apnea-hypopnea index (AHI) from 15.7 [11.3-22.5] to 10.7 [6.6-16.5] events/h; p < 0.001 and increased minimum oxygen saturation from 83.5 [77.5-87] to 87 [81-90]%; p = 0.003. The sleep architecture at baseline and HOBE were similar. However, sleep efficiency increased slightly but significantly with HOBE (87.2 [76.7-90.7] vs 88.8 [81.6-93.3]; p = 0.005). The AHI obtained at the third PSG without HOBE (n = 7) returned to baseline values. Conclusions: Mild HOBE significantly improves OSA severity without interfering in sleep architecture and therefore is a simple alternative treatment to ameliorate OSA.
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SLEEP BREATHING PHYSIOLOGY AND DISORDERS ORIGINAL ARTICLE
The influence of head-of-bed elevation in patients
with obstructive sleep apnea
FábioJoséFabríciodeBarrosSouza
1
&Pedro Rodrigues Genta
2
&
Albino José de Souza Filho
3
&Andrew Wellman
4
&Geraldo Lorenzi-Filho
2
Received: 7 February 2017 /Revised: 21 May 2017 /Accepted: 31 May 2017 /Published online: 24 June 2017
#The Author(s) 2017. This article is an open access publication
Abstract
Purpose The purpose of this study is to test the effects of a
mild degree of head-of-bed elevation (HOBE) (7.5°) on ob-
structive sleep apnea (OSA) severity and sleep quality.
Methods OSA patients were recruited from a single sleep clin-
ic (Criciúma, Santa Catarina, Brazil). Following a baseline
polysomnography (PSG), all patients underwent a PSG with
HOBE (within 2 weeks). In addition, a subset of patients per-
formed a third PSG without HOBE.
Results Fifty-two patients were included in the study (age
53.2 ± 9.1 years; BMI 29.6 ± 4.8 kg/m
2
, neck circumference
38.9 ± 3.8 cm, and Epworth Sleepiness Scale 15 ± 7).
Compared to baseline, HOBE significantly decreased the
apnea-hypopnea index (AHI) from 15.7 [11.322.5] to 10.7
[6.616.5] events/h; p< 0.001 and increased minimum oxy-
gen saturation from 83.5 [77.587] to 87 [8190]%;
p= 0.003. The sleep architecture at baseline and HOBE were
similar. However, sleep efficiency increased slightly but sig-
nificantly with HOBE (87.2 [76.790.7] vs 88.8 [81.693.3];
p= 0.005). The AHI obtained at the third PSG without HOBE
(n= 7) returned to baseline values.
Conclusions Mild HOBE significantly improves OSA sever-
ity without interfering in sleep architecture and therefore is a
simple alternative treatment to ameliorate OSA.
Keywords Obstructive sleep apnea .Therapy .Patient
positioning .Polysomnography
Introduction
Obstructive sleep apnea (OSA) is a common disorder charac-
terized by repetitive partial or complete obstruction of the
upper airway during sleep [13]. The pathophysiology of
OSA is complex and is caused by the interplay of both ana-
tomical and non-anatomical factors including neuromuscular
responsiveness, ventilatory instability, and arousal threshold
[3]. Continuous positive airway pressure (CPAP) is the most
common treatment for OSA. However, CPAP adherence is not
ideal and may be even worse among subjects with milder
forms of OSA [4,5].
Alternative options for OSA treatment include oral appli-
ances, upper airway surgery, oropharyngeal exercises, and po-
sitional therapy [612]. Head-of-bed elevation (HOBE) has
been shown to effectively reduce OSA severity in small stud-
ies [13,14]. However, HOBE was aggressive and ranged from
30° to 60°, making this approach difficult to be tolerated in
clinical practice [1316]. The evidence that HOBE may be
useful to treat OSA also comes from physiological studies
showing that HOBE decreases upper airway collapsibility
and increases upper airway area as compared to supine posi-
tion [1316]. Mild HOBE is widely accepted to treat gastro-
esophageal reflux [17]. Therefore, mild HOBE may be an
attractive and low-cost option to treat OSA either alone or in
combination with other therapies. However, there is very little
evidence to support HOBE effectiveness in clinical practice.
*Fábio José Fabrício de Barros Souza
fsouzapneumo@hotmail.com
1
Pulmonary Division - Hospital São José, Pulmonar Sleep Laboratory
and Universidade do Extremo Sul Catarinense, Antônio de Lucca 91,
4th floor, Pio Correa, Criciúma, Santa Catarina, Brazil
2
Sleep Laboratory, Pulmonary Division, Heart Institute (InCor),
University of São Paulo Medical School, São Paulo, Brazil
3
Pulmonary Division, Hospital São José and Pulmonar Sleep
Laboratory, Criciúma, Santa Catarina, Brazil
4
Division of Sleep Medicine, Brigham and Womens Hospital and
Harvard Medical School, Boston, MA, USA
Sleep Breath (2017) 21:815820
DOI 10.1007/s11325-017-1524-3
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
We hypothesized that a mild HOBE (7.5°) will significantly
improve OSA without interfering on sleep architecture and
efficiency. In order to test these hypotheses, we studied pa-
tients with OSA by full polysomnography (PSG) without
(baseline) and with HOBE.
Methods
Subjects
Men and women aged between 18 and 75 years were recruited
from a sleep clinic in Criciúma, Santa Catarina, Brazil.
Subjects with a body mass index (BMI) > 40 kg/m
2
, a previ-
ous diagnosis of heart failure, renal failure, and uncontrolled
respiratory or neurological disease, and a baseline PSG show-
ing an apnea-hypopnea index <5 events/h were excluded. The
study was approved by the Hospital São José Ethics
Committee, Criciúma, Santa Catarina, Brazil (protocol 167/
2010). Written informed consent was obtained from all pa-
tients before any study procedure. The trial was registered at
clinicaltrials.gov (NCT02088723).
Polysomnography
Polysomnographic recordings were performed using an Alice
5® polysomnography system (Philips Respironics) and com-
prised of electroencephalogram derivations (F4/M1, C4/M1,
O2/M1, F3/M2, C3/M2, O1/M2), electrooculogram,
submental and anterior tibialis electromyogram, and electro-
cardiogram. Airflow was monitored using an oronasal therm-
istor and a nasal pressure cannula. Thoracic and abdominal
movements were registered using inductive plethysmography
belts. Body position and oxygen saturation oximetry were also
recorded. The studies were manually scored according to the
latest American Academy of Sleep Medicine scoring manual
[18]. Apnea was defined as a reduction of 90% of the
oronasal thermistor flow amplitude for 10 s. Hypopnea was
defined as the reduction 30% of nasal pressure flow ampli-
tude for 10 s in association with either 3% arterial oxygen
desaturation or an arousal [18]. Mild, moderate, and severe
OSAwas classified according to standard criteria (514.9, 15
30, >30 events/h, respectively) [19].
Study design
All patients were evaluated by a clinical interview and
Epworth Sleepiness Scale (ESS) questionnaire was applied.
A baseline diagnostic polysomnography was performed
followed by a polysomnography with HOBE within 2 weeks.
The laboratory bed was 2.10 m long and the mattress was at
0.6 m from the floor. A 15-cm-high piece of wood under the
head-of-bed legs was used, resulting in a tilt of 7.5°. Because
this was not a randomized trial, a third polysomnography
without HOBE was performed within the subsequent 2 weeks
in a subset of patients in order to exclude that the possible
differences in OSA severity between baseline and intervention
were not due to random variability.
Statistical analysis
Statistical analysis was performed using SPSS version 20.0. G
Power version 3.0.10 was used for power calculations and
α˂0.05 was considered significant. The Shapiro-Wilk test
was used to test for normal distribution. Paired ttest or
Wilcoxon signed-rank test was used to compare baseline and
HOBE data as appropriate. Sample size was calculated
expecting a 30% decrease in the AHI after HOBE. A beta of
0.85 and alpha of 0.05 were used and 52 patients were neces-
sary. A repeated measurement ANOVA was performed to test
for the difference between the three polysomnographies in the
subset of patients that underwent a third PSG without bed
elevation. A post-hoc analysis (Tukeys) was done to test for
differences between polysomnographies. A positive response
was defined as 50% reduction in AHI or AHI < 5 events/h
during intervention. A partial response was defined as a de-
crease in AHI between 25 and 50%. A negative response was
defined as <25% AHI reduction.
Results
Sixty-two patients were initially evaluated. Ten patients
were excluded because of concomitant chronic obstruc-
tive pulmonary disease (n= 6), BMI > 40 kg/m
2
(n= 2) and two patients did not agree to participate.
Therefore, 52 patients were included in the study. The
time lag between the baseline and HOBE PSG was
8.9 ± 2.1 days. A subset of seven patients performed
a third PSG without HOBE (9.7 ± 2.6 days after the
HOBE PSG) (Fig. 1). The sample consisted of middle
aged (53.2 ± 9.1 years) men and women (25 women)
that were on average overweight (BMI 29.6 ± 4.8 kg/
m
2
, neck circumference 38.9 ± 3.8 cm) with symptoms
of excessive daytime sleepiness (EES 14.7 ± 6.9).
Patients had, on average, moderate OSA at baseline
PSG with an AHI ranging from 5.3 to 44.8 events/h.
Twenty, 28, and 4 patients presented mild, moderate,
and severe OSA, respectively. The median AHI in base-
line PSG was 10.6 [7.612.1] events/h in mild, 17.6
[15.723.3] events/h in moderate, and 39.4 [36.842.4]
events/h in severe OSA patients. Table 1shows the
sleep characteristics during baseline and HOBE PSG.
HOBE did not promote any significant differences in
sleep stages, arousal index (ArI), total sleep time
(TST), or time in supine position. Although HOBE
816 Sleep Breath (2017) 21:815820
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was associated with an increase in sleep efficiency
(from 87.2% [76.790.7] to 88.8% [81.693.3],
p= 0.005), the mean increase was 83.4 ± 9.2 to 91.4 ± 31.6,
and this does not appear to be clinically relevant.
There was on average a 31.8% reduction in AHI during
HOBE. HOBE significantly decreased AHI from 15.7
[11.322.5] to 10.7 [6.616.5] events/h (p< 0.001). HOBE
promoted a greater reduction in the supine AHI (from 20.5
[10.033.2] to 11.3 [5.734.5] events/h, p=0.023).Theindi-
vidual values of AHI at baseline and HOBE PSG can be
observed in Fig. 2. Minimum oxygen saturation increased
significantly during HOBE from 83.5 [77.587] to 87 [81
90]% (p= 0.003). HOBE was most effective to reduce
hypopneas (from 12.9 [8.615.4] to 6.8 [3.711.3] events/h,
p=0.001)(Table1).
Thirteen patients out of 52 patients (25%) presented posi-
tional OSA (defined as an AHI at lateral position less than
50% of the AHI at supine position). Among the 13 patients
showing positional OSA during baseline PSG, 9 maintained
positional OSA with HOBE. Apnea-hypopnea index of the 13
positional OSA patients at the baseline polysomnography
(11.9 [10.414.3] events/h) did not reduce significantly during
HOBE (9.0 [4.69.9] events/h), p=0.174.
Thirty-two patients (61.5%) were classified as responders
to HOBE (9 patients presented a positive response and 23
patients presented a partial response). In contrast, 20 patients
(38.4%) did not respond to HOBE. Among the 7 subjects that
underwent a third polysomnography without HOBE, the AHI
during the third (22.0 ± 13.6 events/h) and baseline
(20.8 ± 10.7events/h) PSGs was similar (p= 0.304) but was
significantly higher than during the HOBE night (14.0 ± 9.1
events/h) p=0.005.
Baseline
Polysomnography
(n=52)
HOBE
Polysomnography
(n=52)
Polysomnography
(no elevation)
(n=7)
Excluded
(n=10)
Clinical
evaluation
(n=62)
Fig. 1 Study flow chart and number of studied and excluded subjects
Tabl e 1 Comparative data
between baseline
polysomnography and HOBE
polysomnography
Baseline Head-of-bed elevation p
TST (min) 359 ± 50 365 ± 34 0.446
Sleep efficiency (%) 87.2 [76.790.7] 88.8 [81.693.3] 0.005
N1 (%) 6.0 ± 3.2 5.8 ± 2.5 0.678
N2 (%) 61.9 ± 12.5 60.2 ± 10.9 0.198
N3 (%) 20.7 ± 12.2 21.2 ± 10.1 0.680
REM (%) 11.3 ± 5.6 12.8 ± 6.4 0.076
ArI (events/h) 9.1 [5.517.7] 8.1 [6.412.4] 0.682
Time in supine position (min) 97.8 ± 98.9 107.1 ± 95.6 0.488
AHI (events/h) 15.7 [11.322.5] 10.7 [6.616.5] <0.001
AHI supine (events/h) 20.5 [10.033.2] 11.3 [8.522.6] 0.023
AHI non-supine (events/h) 12.3 [6.127.2] 8.1 [4.412.4] <0.001
CAI (events/h) 0 [00.3] 0 [00.2] 0.321
OAI (events/h) 2.2 [0.94.7] 2.1 [0.64.4] 0.461
MAI (events/h) 0.2 [00.6] 0.2 [00.5] 0.257
HI (events/h) 12.9 [8.615.4] 6.8 [3.711.3] <0.001
SatO
2
min (%) 83.5 [77.587] 87 [8190] 0.003
Results are shown as median [IQR] or mean ± SD
All the p<0.05inbold
AHI apnea-hypopnea index, CAI central apnea index, OAI obstructive apnea index, MAI mixed apnea index, HI
hypopnea index, SatO
2
min minimum oxygen saturation, TST total sleep time, N1 non-REM sleep stage 1, N2
non-REM sleep stage 2, N3 non-REM sleep stage 3, REM rapid eye movement, ArI arousal index
Sleep Breath (2017) 21:815820 817
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Discussion
The major finding of the current study was that a mild degree
of HOBE (7.5°) was able to reduce OSA severity by 31.8% on
average among patients with predominantly mild to moderate
OSA. HOBE had the largest impact in reducing hypopneas
(47.3%) and supine-dependent respiratory events (44.9%). We
believed that HOBE would reduce sleep efficiency because of
some postural discomfort or falling sensation, but this did not
occur. HOBE was associated with an increase in sleep effi-
ciency, although this does not appear to be clinically relevant.
HOBE may be a simple alternative treatment option for pa-
tients with mild to moderate OSA.
The findings of the present study are in line with previous
reported small case series. For instance, McEvoy et al. studied
13 male patients during the same night and reported a reduc-
tion from 49 ± 5 to 20 ± 7 events/h from supine to sitting
position at 60° [13]. Although the authors reported a greater
decrease in AHI than in our study, the clinical applicability is
limited because patients usually do not tolerate sleeping in the
sitting position for prolonged periods. Skinner et al. reported a
22% reduction in AHI in 14 patients with a wide range of
OSA severity when sleeping with a shoulder-head elevation
pillow [20]. Our study extends these previous findings in a
larger sample with clinical applicability by showing a 31.8%
reduction in median AHI among patients with predominantly
mild to moderate OSA using a HOBE of 7.5°. HOBE was
obtained with a 15-cm wedge (5.9 in.). Similar elevation has
been shown to be well tolerated and used in studies on gas-
troesophageal reflux disease [17]. The magnitude of reduction
in AHI observed in the present study with HOBE (32%) is
similar to that of other non-CPAP alternatives previously
reported such as postural position therapy (46%) [21],
oropharyngeal exercises (39%) [8],and compression
stockings (36%) [22].
The pathophysiology of OSA is complex, may vary from
patient to patient, and involves anatomical and non-
anatomical components, such as respiratory control stability.
The predominant control of hypopneas observed in our study
is consistent with other alternative non-CPAP treatments for
OSA [2325]. Similar effects have been observed in therapeu-
tic approaches that act on the respiratory control stability such
as acetazolamide [23], dead space, and supplemental oxygen
[24] as well as on the mechanical component of OSA such as
the instillation of surfactant [25]. Two independent studies
reported a significant reduction in pharyngeal critical closing
pressure (Pcrit) with HOBE, indicating a protective effect by
acting on the anatomical component of OSA. Neill AM et al.
showed a significant reduction in Pcrit between natural sleep
in the supine position and during 30° HOBE (0.3 ± 2.4 to
4.0 ± 3.2 cmH
2
O, respectively) [14]. In a second study, nine
patients studied under general anesthesia with propofol and
vecuronium, Pcrit also decreased from the supine to the sitting
position at 62° 2.2 (0.846.12) to 3.5 (8.511.32)
cmH
2
O, respectively [16]. In line with the physiological re-
search, one study showed a significant increase in the mean
upperairwayvolume(evaluatedbycervicalcomputedtomog-
raphy) from the supine to the head elevation position with 44°
(40.35 ± 16.43 vs 48.31 ± 16.21 cm
3
, respectively) [26].
HOBE may alleviate the force of gravity on the pharyngeal
structures, especially the tongue. The tongue defines the ante-
rior pharyngeal wall which is particularly susceptible to
narrowing while sleeping supine [14,16,26,27]. HOBE
may also stabilize the upper airway by preventing rostral fluid
shift during sleep, a mechanism that may contribute to upper
airway obstruction not only in patients with edematous states,
but also in typical OSA patients [28].
HOBE is very easy to be applied and well tolerated.
HOBE could be a simple measure for patients that are
waiting for OSA therapy, such as mandibular advanced
device or surgery. HOBE could also be used in combi-
nation with other interventions such as oral appliance,
oropharyngeal exercises, and weight loss in future stud-
ies. HOBE has also the potential of providing a better
compliance than other alternative therapies for OSA
Fig. 2 Individual AHI values obtained during baseline and HOBE
polysomnographies. Filled squares are median values [interquartile
range]
818 Sleep Breath (2017) 21:815820
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such as oropharyngeal exercises and positional therapy.
For instance, avoiding supine position with tennis ball
therapy showed that the long-term patient compliance is
poor, with less than 10% of adherence [29].
Our study has several potential limitations. Firstly,
this was not a randomized study, and therefore, it is
not possible to exclude the impact of difficult to control
variables such as the first night PSG effect. However, in
a small subgroup of patients that performed a third PSG
with no HOBE, it clearly showed a return of OSA se-
verity to the baseline levels. Secondly, one may argue
that the effect of HOBE on OSA severity was mild and
that a higher degree of bed elevation could be more
effective in reducing OSA severity. The elevation
adopted in our study was a compromise between effec-
tiveness and comfort. A pilot study (data not shown)
showed that patients did not tolerate sleeping with a
20-cm wedge because of sensation of falling. We there-
fore adopted a bed angulation that is well described in
patients with gastroesophageal reflux. Thirdly, the ma-
jority of our patients had only mild to moderate OSA,
and the effects were more pronounced in reducing
hypopneas than apneas. Therefore, the effects of
HOBE are more likely to be less evident in patients
with severe OSA. Fourthly, HOBE may be contra indi-
cated in patients with specific conditions such as lower
limb edema and venous insufficiency.
Conclusions
HOBE is a simple measure that significantly improves OSA
severity without compromising the sleep architecture. This
positional intervention reduces AHI and has better effects in
hypopnea index and supine AHI. Due its simplicity and low
cost, HOBE can be an attractive alternative treatment for
OSA.
Compliance with ethical standards
Funding No funding was received for this research. Dr. Geraldo
Lorenzi Filho and Pedro Rodrigues Genta were supported by FAPESP.
Conflict of interest The authors declare that they have no conflict of
interest.
Ethical approval All procedures performed in studies involving hu-
man participants were in accordance with the ethical standards of the
institutional and/or national research committee and with the 1964
Helsinki declaration and its later amendments or comparable ethical
standards.
Informed consent Informed consent was obtained from all individual
participants included in the study.
Open Access This article is distributed under the terms of the Creative
Commons Attribution 4.0 International License (http://
creativecommons.org/licenses/by/4.0/), which permits unrestricted use,
distribution, and reproduction in any medium, provided you give appro-
priate credit to the original author(s) and the source, provide a link to the
Creative Commons license, and indicate if changes were made.
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... In some OSA patients, the frequency and duration of apneas could be influenced by head and body positions that are traditionally considered to be supine, prone, or lateral decubitus. Patients who present a reduction in the number or duration of apneas/hypopneas, related to changes in their sleeping position, have been classified as having position-dependent OSA (POSA) [4][5][6][7][8][9][10][11][12][13]. However, it should be considered that supine, prone, and lateral decubitus are not the only types of sleep positions possible. ...
... Souza et al. [11] have shown the effects of a mild degree of HOBE (7.5 • elevation) on OSA severity and sleep quality. Fifty-two patients were evaluated. ...
... In our setting, lifting the patient's trunk by just 30 • brought about an improvement of the antero-posterior diameter, as well of the lateral diameter. This data was in line with the physiological research reported by Souza et al. [11], which showed a significant increase in the mean upper airway volume, using a cervical computed tomography, from the supine to the head and trunk elevation position at 44 • (40.35 ± 16.43 vs. 48.31 ± 16.21 cm 3 , respectively). ...
Article
Full-text available
Purpose: Evaluate the effectiveness of the head-of-bed elevation position (HOBE) with a 30° elevation of the head and trunk, in improving obstruction of the upper airways in obstructive sleep apnea (OSA) patients. A prospective trial simultaneously performing drug-induced sleep endoscopy (DISE) and polysomnography (PSG) tests was performed. Methods: Forty-five patients were included in the prospective study protocol. All patients enrolled in the study and underwent the following evaluations: (1) a drug-induced sleep endoscopy, with an evaluation of obstructions and collapse of the upper airways at 0° and in a HOBE position, with head and trunk elevation of 30°; (2) an overnight PSG assessment in the hospital with head and trunk elevation from 0° to 30° during the night; (3) a questionnaire to evaluate the feedback of patients to sleeping with head-of-bed elevation. Results: Velum (V) and oropharynx lateral wall (O) collapses were reduced in the 30° up position. There were no statistical differences that emerged in the obstruction of the tongue base and epiglottis between the 0° position and the 30° up position (p > 0.05). The average AHI score changed from 23.8 ± 13.3 (0° supine position) to 17.7 ± 12.4 (HOBE position), with a statistical difference (p = 0.03); the same statistical difference emerged in the percentage of apneas that decreased from 55 ± 28.1 to 44 ± 25.8 (p = 0.05). Conclusions: By adopting the HOBE position with 30° elevation of the head and trunk, it is possible to obtain a reduction of upper airways collapses and an improvement of apnea/hypopnea events and nightly respiratory outcomes.
... For example, Skinner et al [4] reported mixed results after testing a shoulder-head elevation pillow for the management of obstructive sleep apnea (OSA). More recently, Souza et al [5] showed that head-of-bed elevation using a laboratory bed reduced the severity of OSA without interfering with sleep architecture. Similarly, a study of a bed that automatically lifted the trunk of the user upon detection of snoring found that it was able to reduce episodes of snoring in the laboratory [6]. ...
... The 12-degree angle is sufficient to elevate the head while still being comfortable for sleep. A mild degree of head-of-bed elevation, compared to larger angles, is most likely to be well tolerated while still being effective according to laboratory studies [5,6]. The inclined position was hypothesized to reduce snoring and improve sleep. ...
... In conclusion, sleeping with the upper body at an incline has potential as a simple nonobtrusive means of reducing snoring and improving sleep in a nonclinical snoring population. This sleeping position is thought to lead to benefits by decreasing upper airway collapsibility and increasing the upper airway area, compared to the flat position, leading to improved breathing and, in turn, better sleep [5]. Elevating the upper body at night is also frequently recommended to alleviate heartburn symptoms and improve sleep in individuals experiencing nocturnal gastroesophageal reflux [14]. ...
Article
Full-text available
Background Accurately and unobtrusively testing the effects of snoring and sleep interventions at home has become possible with recent advances in digital measurement technologies. Objective The aim of this study was to examine the effectiveness of using an adjustable bed base to sleep with the upper body in an inclined position to reduce snoring and improve sleep, measured at home using commercially available trackers. Methods Self-reported snorers (N=25) monitored their snoring and sleep nightly and completed questionnaires daily for 8 weeks. They slept flat for the first 4 weeks, then used an adjustable bed base to sleep with the upper body at a 12-degree incline for the next 4 weeks. Results Over 1000 nights of data were analyzed. Objective snoring data showed a 7% relative reduction in snoring duration (P=.001) in the inclined position. Objective sleep data showed 4% fewer awakenings (P=.04) and a 5% increase in the proportion of time spent in deep sleep (P=.02) in the inclined position. Consistent with these objective findings, snoring and sleep measured by self-report improved. Conclusions New measurement technologies allow intervention studies to be conducted in the comfort of research participants’ own bedrooms. This study showed that sleeping at an incline has potential as a nonobtrusive means of reducing snoring and improving sleep in a nonclinical snoring population.
... It has been reported that sleep in an angle-adjustable chair, such as a recliner, improved the sleep quality through the sleep at a higher angle of posture or the neck [20][21][22]. In particular, it has been proven that some sleep disorders could be medically improved in patients with sleep apnea [22][23][24][25] and nocturnal gastroesophageal reflux through sleep in a recliner [26]. In this paper, we propose an additional way to further improve the quality of sleep with providing a rocking motion to the recliner. ...
Article
Full-text available
In this study, we analyze the effect of a recliner chair with rocking motions on sleep quality of naps using automated sleep scoring and spindle detection models. The quality of sleep corresponding to the two rocking motions was measured quantitatively and qualitatively. For the quantitative evaluation, we conducted a sleep parameter analysis based on the results of the estimated sleep stages obtained on the brainwave and spindle estimation, and a sleep survey assessment from the participants was analyzed for the qualitative evaluation. The analysis showed that sleep in the recliner chair with rocking motions positively increased the duration of the spindles and deep sleep stage, resulting in improved sleep quality.
... high piece of wood under the head-of-bed legs. 32,33 Nasal irrigation to avoid congestion: Furthermore, because this pandemic is spanning the spring/summer, nasal irrigation with a saline solution is another treatment recommendation. Congestion due to seasonal allergies may also obstruct the airways and over-the-counter solutions are available for patients who experience seasonal allergies. ...
Article
Full-text available
STUDY OBJECTIVES:In the context of the current COVID-19 pandemic situation, we address the following important questions: (1) How can patients be identified for possible obstructive sleep apnea (OSA) while sleep clinic testing is temporarily unavailable or limited? and (2) What measures can be suggested to improve sleep health until proper diagnosis and treatment become safe and available again? METHODS:As a proxy for home or in-lab testing, validation of a symptom-based measure of OSA risk is presented, based on an on-going larger prospective study of 156 family medicine patients with OSA (88 women, 68 men; mean age 57) and 60 Control participants (36 women, 24 men; mean age 54) recruited from the community. Participants completed the Sleep Symptom Checklist (SSC) as well as a range of other self-report measures; primary care patients also underwent a polysomnographic sleep study. RESULTS:Results show (a) that individuals with OSA reported more symptoms on the SSC related to Insomnia, Daytime Symptoms, Sleep Disorders and Psychological Maladjustment than the Control group (all p<.001), and (b) that their sleep-related symptoms were significantly more severe than those of Controls. In addition, (c) several PSG indices in recently diagnosed, untreated individuals with OSA were significantly correlated with SSC measured Sleep Disorder symptoms, and (d) SSC scores significantly distinguished OSA participants from Controls. CONCLUSIONS:Our findings suggest that family practitioners can effectively pre-screen patients for possible OSA by inquiring about 5 items that form the SSC Sleep Disorders subscale. If OSA is suspected, there are a range of behavioral techniques which we recommend to improve symptoms. The current pandemic causes us to reflect that provisional targeting of symptoms and guidance as to mitigation strategies while waiting for specialist care could serve patients well at any time.
... Souza et al. have evaluated the influence of head-of-bed elevation on OSA severity and sleep quality [30]. Most patients in their study were diagnosed with mild to moderate OSA. ...
Article
Full-text available
PurposeThis study aimed to evaluate the difference of upper airway collapse between the back-up head-elevated position (a 45° upward inclination) and supine position to better elucidate the role of back-up head-elevated position in reductions of obstructive sleep apnea (OSA) severity.Methods From August 2016 to May 2019, 198 patients aged between 18 and 70 years were recruited in this study prospectively. Drug-induced sleep endoscopy (DISE) findings were recorded with the patients first placed in the supine position then into the back-up head-elevated position with a 45° upward inclination.ResultsFrom the supine to back-up head-elevated position, a significant decrease in the severity of collapse was observed in velum anteroposterior collapse and velum concentric collapse (p < 0.001 and p < 0.001, respectively), which was more predominant in patients with mild OSA than in patients with moderate to severe OSA. On the other hand, there was no significant improvement of any other collapse at the level of oropharynx, tongue base, or epiglottis when the position was shifted from the supine into back-up head-elevated position.Conclusions The back-up head-elevated position with a 45° upward inclination improved upper airway obstruction during DISE in velum anteroposterior collapse and velum concentric collapse. The proportion of patients with amelioration of upper airway collapse was much higher in patients with mild OSA than in patients with moderate to severe OSA. The back-up head-elevated position may be a reasonable alternative to traditional positional therapy for certain subgroups of patients with OSA.
Chapter
Dental sleep appliances achieve a 50% response in around 65% of patients with obstructive sleep apnea and a complete response in 35–40%. This means that all practitioners will need to augment the effect of a dental sleep appliance at some stage. There are many ways in which adjunctive therapies can be used to augment both the objective and subjective outcomes of DSA therapy. This chapter discusses the use of multiple adjunct therapies including positional therapies, positive airway pressure therapies, therapies aimed at stabilizing or improving compromised anatomy in the upper airway, and therapies aimed at improving the subjective outcomes of sleep.KeywordsDental sleep applianceObstructive sleep apneaPositional obstructive sleep apneaCognitive behavioral therapy for insomniaCircadian rhythm disordersBright light therapyOral EPAPNasal EPAP
Chapter
Nasal congestion affects a large part of the population and is one of the most common symptoms in otolaryngological practice. A detailed history and physical examination are important to reach the diagnosis. Endoscopic examination of the nose is the most valuable examination method in the evaluation of nasal obstruction. In endoscopic examination, nasal mucosa and its features, pathologies of anatomical structures (septal deviation, septal perforation, turbinate hypertrophy etc.), nasal discharge and its characteristics, intranasal masses (polyp, tumor, etc.), and the nasopharynx are evaluated.KeywordsNasal obstructionRhinitisOtolaryngologyPregnancyPostpartum period
Article
Background Low acceptance rate of continuous positive airway pressure therapy in postoperative patients with untreated obstructive sleep apnea (OSA) indicates the necessity for development of an alternative postoperative airway management strategy. We considered whether the combination of high-flow nasal cannula and upper body elevation could improve postoperative OSA. Methods This non-blinded randomized crossover study performed at a single university hospital investigated the effect on a modified apnea hypopnea index, based exclusively on the airflow signal without arterial oxygen saturation criteria (flow-based apnea hypopnea index, primary outcome), of high-flow nasal cannula (20 liter.minute-1 with 40% oxygen concentration) with and without upper body elevation in patients with moderate to severe OSA. Preoperative sleep studies were performed at home (control, no head-of-bed elevation) and in hospital (30-degree head-of-bed elevation). On the first and second postoperative nights, high-flow nasal cannula was applied with or without 30-degree head-of-bed elevation, assigned in random order to 23 eligible participants. Results Twenty-two out of the 23 (96%) accepted high-flow nasal cannula. Four participants resigned from the study. Control flow-based apnea hypopnea index (mean±SD: 59.6 ± 12.0 events.hour-1, n=19) was reduced by 14.7 (95% CI: 5.5 to 30.0) events.hour-1 with head-of-bed elevation alone (p=0.002), 10.9 (1.2 to 20.6) events.hour-1 with high-flow nasal cannula alone (p=0.028), and 22.5 (13.1 to 31.9) events.hour-1 with combined head-of-bed elevation and high-flow nasal cannula (p<0.001). Compared to sole high-flow nasal cannula, additional intervention with head-of-bed elevation significantly decreased flow-based apnea hypopnea index by 11.5 events.hour-1 (1.7 to 21.4) (p=0.022). High-flow nasal cannula, alone or in combination with head-of-bed elevation also improved overnight oxygenation. No harmful events were observed. Conclusion The combination of high-flow nasal cannula and upper body elevation reduced OSA severity and nocturnal hypoxemia, suggesting a role for it as an alternate postoperative airway management strategy.
Article
Full-text available
Objectives While obstructive sleep apnea (OSA) is associated with several chronic health conditions such as hypertension, obesity, and chronic hypoxia, there is limited information on its association with neuromuscular and spinal pathologies that may be of interest to a musculoskeletal (MSK) medicine or pain management clinician. The objective of this study was to perform a systematic literature review to examine the association between OSA and cervical spine pathologies, postural changes, and pain. Design We systematically reviewed PubMed and Embase databases up to 4/15/2019. We included studies that explored associations between OSA and a) pain, b) postural characteristics or changes, or c) cervical spine morphology. Systematic reviews, meta-analysis, randomized control trials, cohort studies, and case–control studies were included. Case reports, narrative reviews or expert opinion papers were excluded. From the articles that met selection criteria, information regarding type, direction and magnitude of such associations was extracted. The OSA-pain association studies were further divided into 3 subgroups: neuropathic, temporomandibular, and chronic pain. Results 21 articles that met our study criteria were selected for this review. Two studies were on cervical spine pathologies, eight on postural changes, and eleven on pain associated with OSA. Exploring the association between OSA and cervical spine pathologies, postural changes, and pain in this systematic review we found: (1) Cervical spine lesions, fusions, and abnormalities that reduce retropharyngeal space are associated with OSA, likely by way of worsening posture and decreasing range of motion. (2) Head extension and anteriorization are associated with OSA likely as a compensatory mechanism. Extension may improve airway function, while anteriorization helps to maintain visual sense. (3) Head-of-bed-elevation may improve OSA symptoms and can possibly supplement other conservative treatment measures. (4) Neuropathic pain is associated with OSA, likely by way of inflammatory pathways. (5) Oral appliance use (eg mandibular advancement/protruding device) in OSA likely contributes to transient temporomandibular pain. (6) There is little association between OSA and chronic pain prevalence. (7) Increased pain intensity and decreased pain tolerance are somewhat associated with OSA, likely by way of hypoxemia and sleep fragmentation. Conclusions Clinicians in MSK and pain medicine need to consider these associations and consider obtaining imaging studies and/or making referrals for management of their OSA to better provide appropriate care to these patients.
Article
Full-text available
Objective: Obstructive sleep apnea syndrome (OSAS) has a high prevalence and carries significant cardiovascular risks. It is important to study new therapeutic approaches to this disease. Positional therapy might be beneficial in reducing the apnea-hypopnea index (AHI). Imaging methods have been employed in order to facilitate the evaluation of the airways of OSAS patients and can be used in order to determine the effectiveness of certain treatments. This study was aimed at determining the influence that upper airway volume, as measured by cervical CT, has in patients diagnosed with OSAS. Methods: This was a quantitative, observational, cross-sectional study. We evaluated 10 patients who had been diagnosed with OSAS by polysomnography and on the basis of the clinical evaluation. All of the patients underwent conventional cervical CT in the supine position. Scans were obtained with the head of the patient in two positions (neutral and at a 44° upward inclination), and the upper airway volume was compared between the two. Results: The mean age, BMI, and neck circumference were 48.9 ± 14.4 years, 30.5 ± 3.5 kg/m2, and 40.3 ± 3.4 cm, respectively. The mean AHI was 13.7 ± 10.6 events/h (range, 6.0-41.6 events/h). The OSAS was classified as mild, moderate, and severe in 70%, 20%, and 10% of the patients, respectively. The mean upper airway volume was 7.9 cm3 greater when the head was at a 44° upward inclination than when it was in the neutral position, and that difference (17.5 ± 11.0%) was statistically significant (p = 0.002). Conclusions: Elevating the head appears to result in a significant increase in the caliber of the upper airways in OSAS patients.
Article
Full-text available
To examine whether a social cognitive therapy (SCT) intervention increases continuous positive airway pressure (CPAP) use compared to equivalent social interaction (SI) time. Individuals with obstructive sleep apnea (OSA) referred for CPAP therapy. Participants received a 30-min group education session regarding OSA and CPAP. Groups of three to four participants were then randomly assigned to an SCT session or social interaction. CPAP usage was assessed at 7 nights, then 1, 3, and 6 months. The two primary outcomes were adherence, usage ≥ 4 h per night at 6 months, and uptake of CPAP. Questionnaires were given pretreatment and posttreatment. Two hundred six individuals were randomized to SI (n = 97) or SCT (n = 109). CPAP uptake was not different between groups (82% in SI, 88% in SCT groups, P = 0.35). There were no differences between groups in adherence: 63-66% at 1 week, and at 6 months 55-47% (P = 0.36). Higher pretreatment apnea-hypopnea index, higher baseline self-efficacy, and use of CPAP (≥ 4 h) at 1 week were independent predictors of CPAP adherence at 6 months. CPAP adherence increased by a factor of 1.8 (odds ratio = 1.8, 95% confidence interval 1.1-3.0) for every one-unit increase in self-efficacy. There was no difference between groups postintervention in self-efficacy scores, sleepiness, mood, or sleep quality. In this randomized trial, a single SCT application did not increase adherence when compared with SI time. Although self-efficacy scores prior to CPAP predicted adherence, self-efficacy was not increased by the interventions. Increasing intensity and understanding of SCT interventions may be needed to improve CPAP adherence. Australian New Zealand Clinical Trials Registry, ACTRN12607000424404. Bartlett D; Wong K; Richards D; Moy E; Espie CA; Cistulli PA; Grunstein R. Increasing adherence to obstructive sleep apnea treatment with a group social cognitive therapy treatment intervention: a randomized trial. SLEEP 2013;36(11):1647-1654.
Article
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Rationale: The pathophysiologic causes of obstructive sleep apnea (OSA) likely vary among patients but have not been well characterized. Objectives: To define carefully the proportion of key anatomic and nonanatomic contributions in a relatively large cohort of patients with OSA and control subjects to identify pathophysiologic targets for future novel therapies for OSA. Methods: Seventy-five men and women with and without OSA aged 20-65 years were studied on three separate nights. Initially, the apnea-hypopnea index was determined by polysomnography followed by determination of anatomic (passive critical closing pressure of the upper airway [Pcrit]) and nonanatomic (genioglossus muscle responsiveness, arousal threshold, and respiratory control stability; loop gain) contributions to OSA. Measurements and main results: Pathophysiologic traits varied substantially among participants. A total of 36% of patients with OSA had minimal genioglossus muscle responsiveness during sleep, 37% had a low arousal threshold, and 36% had high loop gain. A total of 28% had multiple nonanatomic features. Although overall the upper airway was more collapsible in patients with OSA (Pcrit, 0.3 [-1.5 to 1.9] vs. -6.2 [-12.4 to -3.6] cm H2O; P <0.01), 19% had a relatively noncollapsible upper airway similar to many of the control subjects (Pcrit, -2 to -5 cm H2O). In these patients, loop gain was almost twice as high as patients with a Pcrit greater than -2 cm H2O (-5.9 [-8.8 to -4.5] vs. -3.2 [-4.8 to -2.4] dimensionless; P = 0.01). A three-point scale for weighting the relative contribution of the traits is proposed. It suggests that nonanatomic features play an important role in 56% of patients with OSA. Conclusions: This study confirms that OSA is a heterogeneous disorder. Although Pcrit-anatomy is an important determinant, abnormalities in nonanatomic traits are also present in most patients with OSA.
Article
Full-text available
To determine how the OSA patient's pathophysiologic traits predict the success of the treatment aimed at stabilization or increase in respiratory motor outputs, we studied 26 patients with OSA (AHI 42±5 events/hour with 92% of apnea were obstructive), who were treated with O2 supplementation, an isocapnic rebreathing system in which CO2 was added only during hyperpnea to prevent transient hypocapnia, and a continuous rebreathing system. We also measured each patient's controller gain below eupnea (ΔVE/ΔPETCO2, CO2 reserve (eupnea-apnea threshold PETCO2) and plant gain (ΔPETCO2/ΔVE) as well as passive upper airway closing pressure (Pcrit). With isocapnic rebreathing, 14/26 reduced their apnea-hypopnea index (AHI) to 31±6% of control (p<0.01) (responder); 12/26 did not show significant change (non-responder). The responders vs. non-responders had a greater controller gain (6.5±1.7 vs. 2.1±0.2 L/min/mmHg, p<0.01) and a smaller CO2 reserve (1.9±0.3 vs. 4.3±0.4mmHg, p<0.01) with no differences in Pcrit (-0.1±1.2 vs. 0.2 ±0.9 cmH2O, p>0.05). Hypercapnic rebreathing (+4.2±1 mmHg PETCO2) reduced AHI to 15±4% of control (P<0.001) in 17/21 subjects with a wide range of CO2 reserve. Hyperoxia (SaO2 ~95-98%) reduced AHI to 36±11% of control in 7/19 OSA patients tested. We concluded that stabilizing central respiratory motor output via prevention of transient hypocapnia prevents most OSA in selected patients with a high chemosensitivity and a collapsible upper airway; whereas increasing respiratory motor output via moderate hypercapnia eliminates OSA in most patients with a wider range of chemosensitivity and CO2 reserve. Reducing chemosensitivity via hyperoxia had a limited and unpredictable effect on OSA.
Article
To assess the feasibility and efficacy of sleep position modification in preventing supine sleep and improving sleep-disordered breathing and relevant clinical outcomes in positional Obstructive Sleep Apnea (OSA) patients. Eighty-six consecutive participants with moderate positional OSA on routine diagnostic polysomnography underwent a randomized controlled parallel group design trial of 4-weeks treatment using a sleep position modification device (active) or sleep hygiene advice (control). Outcomes were measured at baseline and following a 4-week treatment period. There was a significant reduction in the amount of supine sleep in the active group (mean ± SD change from baseline, active group 99.5 ± 85.2 minutes, control group 68.6 ± 103.2 minutes, p = 0.002), and an improvement in apnea-hypopnea index (AHI) (active group reduced by 9.9 ± 11.6, control group reduced by 5.3 ± 13.9, p = 0.013). Post-hoc analyses indicated that positional therapy was most effective for patients with baseline AHI cut-off above 20 (p = 0.02). Logistic regression showed that a treatment response (AHI < 10) was more likely in the active group (OR = 5.57), and those with higher baseline nadir oxygen desaturation (OR = 1.95) and non-supine AHI (OR = 0.55). There were no significant improvements in quality of life, daytime sleepiness, mood, symptoms, neuropsychological measures or blood pressure in the active group. The position device utilized in this study was effective in reducing supine sleep and AHI, which was significant in those with baseline AHI ≥20. Longer duration studies of physical treatments that modify sleep position are needed to explore further whether additional clinical benefits in are achievable. Copyright © 2015 Elsevier B.V. All rights reserved.
Article
Objectives/HypothesisThis study aimed to evaluate changes in obstruction site in obstructive sleep apnea (OSA) patients according to sleep position.Study DesignProspective case series.Methods Eighty-five patients who had undergone level 1 sleep study and drug-induced sleep endoscopy in the supine and lateral positions were included. Obstruction sites were classified as soft palate (SP), tongue base (TB), lateral wall (LW), and larynx (LX). Subgroup analysis was performed according to lateral apnea-hypopnea index (AHI): those with an AHI of ≥ 10 (lateral obstructors, LO) and those with an AHI of < 10 (lateral nonobstructors, LNO).ResultsPrevalence in obstruction site of SP, TB, and LX decreased significantly after change from supine to lateral position (P < 0.05). However, the prevalence of LW obstruction was not affected by position change. LW collapse in moderate OSA decreased (from 66.7% to 35.9%) after change to lateral sleep, whereas it persisted in severe OSA patients (81.6%–89.5%). In the lateral position, persistent obstruction at the LW was observed more frequently in the LO group compared to the LNO group (83.3% vs. 33.3%).Conclusion When sleep posture is changed from supine to lateral, obstruction due to structures such as tongue base and larynx improves dramatically. Obstruction in lateral position is mostly due to obstruction at the oropharyngeal LWs. Therefore, position dependency is mostly determined by LW collapsibility. Evaluating the changes of the upper airway according to sleep position can further characterize the upper airway collapsibility and can be used for tailored treatment planning.Level of EvidenceLevel 4 (case series). Laryngoscope, 2014
Article
Obstructive sleep apnea (OSA) is a sleep disorder which has been gradually accepted as an important cause of increased morbidity and mortality. The treatment of moderate-severe OSA has improved dramatically since the introduction of continuous positive airway pressure (CPAP) devices; however, the adherence of patients to CPAP treatment is relatively low. Adherence appears to be even worse in patients with mild or asymptomatic OSA. The failure to identify and treat mildly symptomatic or asymptomatic OSA patients may be costly, as such patients comprise about 20% of the general adult population. OSA patients could be divided into positional and non-positional patients. Positional patients show most of their breathing abnormalities while sleeping in the supine position. Simply, by sleeping in the lateral postures, they eliminate or reduce significantly the number of apneas and hypopneas. On the contrary, non-positional patients suffer from breathing abnormalities in the supine and lateral postures, and as a consequence those are the most severe OSA patients for whom CPAP is the treatment of choice. In this paper we intend to argue that positional therapy, i.e. avoidance of the supine posture during sleep, could represent a valuable therapy mainly for mild-moderate OSA. Considering the fact that the vast majority of mild-moderate OSA patients are positional patients (between 65 and 87%), positional therapy may be a simple, cheap and effective solution for them. High-quality research regarding this issue is needed to evaluate the real effectiveness of this mode of therapy.
Article
Background: Sleep-disordered breathing (SDB) is a spectrum of airway collapse, ranging from primary snoring to profound obstructive sleep apnea (OSA). Studies have shown an association between impaired nasal breathing and SDB; consequently, treatments of nasal obstruction are often used in an attempt to improve disease severity. The authors performed a review of the literature to determine the impact of nasal obstruction and the effectiveness of nonsurgical and surgical interventions on SDB. Methods: Relevant literature up to 2012 on the association between nasal obstruction and SDB and effectiveness of nonsurgical and surgical treatment of the nose in SDB were reviewed. Results: The literature is mostly limited to uncontrolled case series in which patient groups, interventions, disease definitions, and outcome measures are not standardized. Nasal medications, including intranasal steroids and nasal decongestants, have not been shown to improve either snoring or OSA. Nasal dilators have no impact on OSA but may improve snoring. Surgery for nasal obstruction does not improve objective indicators of SDB but can improve subjective elements of disease, such as snoring, sleepiness, and quality of life. Nasal surgery can facilitate continuous positive airway pressure use in cases where nasal obstruction is the factor limiting compliance. Conclusion: Nasal obstruction plays a modulating, but not causative, role in SDB. Nasal interventions may improve subjective aspects of snoring and OSA but do not improve objective indicators of disease. Standardization of methods and higher evidence level studies will further clarify the benefit of nasal interventions in the treatment of SDB.