SLEEP 2011 Abstract Supplement

B. Clinical Sleep Science I. Sleep Disorders – Breathing
0384
POLYSOMNOGRAPHIC ANALYSIS OF nREM
CYCLIC ALTERNATING PATTERN (CAP) SLEEP
MICROARCHITECTURE IN COMPLEX AND OBSTRUCTIVE
SLEEP APNEA SYNDROMES
Junna M 1 , St. Louis EK 1 , Dennhardt J 1,2 , Christner M 1,3 , Dresow MW 1 ,
Dueffert LG 1 , Shepard P 1,3 , Westholm H 1,3 , Morgenthaler TI 1
1
Center for Sleep Medicine, Departments of Neurology and Internal
Medicine, Mayo Clinic and Foundation, Rochester, MN, USA,
2
University of Memphis School of Medicine, Memphis, TN, USA, 3 St.
Olaf College, Northfield, MN, USA
Introduction: Complex sleep apnea syndrome (CompSAS) presumably
involves unstable ventilatory control mechanisms, possibly including
cortical brain arousal indexed by NREM cyclic alternating pattern
(CAP) sleep microarchitecture. CompSAS has been associated with
opiate use, but may also be idiopathic or associated with underlying cardiac
disease. We aimed to determine whether CAP sleep rates differed
between CompSAS subgroups (opiate users (OU) and non-opiate users
(NOU)) and non-opiate user OSA controls.
Methods: 34 consecutive CompSAS patients (12 OU, 22 NOU) and
18 OSA controls matched for age, sex, BMI, and AHI were manually
analyzed for CAP sleep rate during diagnostic polysomnography using
Hypnolab scoring software (Verona, Italy). CAP sleep rate during diagnostic
polysomnography in all patients was obtained. Group averages
were compared utilizing Wilcoxon Rank Sum tests in JMP (Chicago,
IL).
Results: CAP rate was significantly lower in CompSAS OU vs. NOU
(62.1 vs. 79.3, p=0.01), and lower in CompSAS OU than OSA controls
(62.1 vs. 74.0, p=0.079). There was no significant difference between
CompSAS NOU and OSA controls.
Conclusion: CompSAS OU had a significantly lower CAP rate than
NOU, and OU also trended toward a lower CAP rate than non-opiate
user OSA controls. Since CAP sleep microarchitecture may reflect cortical
infraslow oscillations, our findings suggest that cortical mechanisms
associated with unstable ventilatory effort in CompSAS and OSA are
similar, but that opiate use may induce central apnea through a different,
likely subcortical mechanism. Further analysis of CompSAS patients
including co-morbid cardiac disease influences may further clarify differences
in cortical arousal potential for central apnea.
0385
IS THERE A DIFFERENCE IN CONTINUOUS POSITIVE
AIRWAY PRESSURE REQUIREMENT OR DISEASE
CONTROL BETWEEN NASAL AND ORONASAL MASKS IN
THE TREATMENT OF OBSTRUCTIVE SLEEP APNEA?
Bakker JP, Neill A, Campbell A
Department of Medicine, University of Otago, Wellington, New
Zealand
Introduction: The aim of this randomized controlled pilot trial was to
investigate whether there is a difference in continuous positive airway
pressure (CPAP) requirement or residual apnea-hypopnea index (AHI)
between nasal and oronasal masks.
Methods: Adult patients (≥25 years) with severe obstructive sleep apnea
(OSA) established on CPAP using a nasal mask within the previous
three years were recruited. All were fitted with two oronasal masks (A
and B) in addition to their own nasal mask, and were excluded if leak
was >20 liters/minute at 8cmH2O while awake. Patients were randomized
to CPAP at manually-titrated pressure, or auto-adjusting positive
airway pressure (APAP) for seven nights each, with immediate crossover.
Within each week, the two oronasal masks were used for two
nights each and the nasal mask for three nights, in random order.
Results: Twelve patients (mean±SD body mass index 37.7±5.0 kg/m2,
AHI 59.8±28.6 events/hour, CPAP 11.1±3.2 cmH2O) consented to the
study. There was no significant difference in APAP 95th percentile pressure
between the three mask types (mean±SD 11.6±2.8, 11.5±3.7 and
11.6±3.2 cmH2O for nasal, oronasal A and oronasal B masks respectively,
p=0.66). Six and five patients demonstrated a 95th percentile pressure
difference of >1cmH2O with oronasal masks A and B respectively,
compared with the nasal mask. The difference in 95th percentile pressure
requirement was not strongly correlated with the difference in 95th
percentile leak (nasal vs. oronasal A r=-0.36, p=0.12; nasal vs. oronasal
B r=-0.29, p=0.18). The machine-interpreted residual AHI during CPAP
use was significantly difference between the masks (mean±SD 1.3±1.5,
4.4±8.1 and 2.7±2.5 events/hour for nasal, oronasal A and oronasal B
masks respectively, p=0.03).
Conclusion: This pilot randomized controlled trial found variation in
pressure requirement between nasal and oronasal masks but was not statistically
significant. This should be further investigated in an adequately
powered trial.
0386
CLINICAL PREDICTORS OF EFFECTIVE CONTINUOUS
POSITIVE AIRWAY PRESSURE IN PATIENTS WITH
OBSTRUCTIVE SLEEP APNEA/HYPOPNEA SYNDROME
Lin H 1 , Friedman M 2
1
Dept. of Otolaryngology, Chang Gung Memorial Hospital, Kaohsiung
Medical Center, Fong Shang City, Taiwan, 2 Otolaryngology, Rush
University & Advocate Illinois Masonic Medical Center, Chicago, IL,
USA
Introduction: To identify standard clinical parameters that may predict
the optimal continuous positive airway pressure (CPAP) in patients with
obstructive sleep apnea/hypopnea syndrome (OSAHS) in Taiwanese.
Methods: One hundred twenty-nine OSAHS patients who underwent
a completed physical examination, successful manual CPAP titration
were included in this study. We recorded the severity of nasal obstruction,
modified Mallampati grade (aka updated Friedman’s tongue position
(uFTP)), tonsil size, neck circumference and body mass index
(BMI) and measured thyroid-mental distance and hyoid-mental distance
(HMD) in the study population.
Results: When the physical parameters were correlated singly with the
optimal CPAP, we found that uFTP, HMD and apnea/hypopnea index
(AHI) were reliable predictors of OSA (P = 0.013, P = 0.002, P = 0.000,
by Multiple Regression). When all important factors were considered in
a stepwise multiple linear regression analysis, a significant correlation
with optimal CPAP was formulated by factoring the uFTP, HMD and
AHI (Optimal CPAP = 1.01 uFTP + 0.74 HMD + 0.059 AHI - 1.603).
Conclusion: This study has distinguished the correlation between updated
Friedman’s tongue position, hyoid-mental distance, and AHI with
the optimal CPAP. The structure of upper airway (esp. tongue base obstruction)
and disease severity may predict the level of optimal CPAP.
0387
THE EFFECTIVENESS OF TREATMENT APNEA-HYPOPNEA
INDEX (ET-AHI): A NEW METHOD TO ASSESS THE
THERAPEUTIC CONTROL OF OBSTRUCTIVE SLEEP
APNEA
Boyd SB, Walters AS, Wang L, Song Y, Malow BA
Vanderbilt University, Nashville, TN, USA
Introduction: CPAP is highly efficacious, but the clinical effectiveness
may be diminished due to non-adherence. In this study we assessed an
innovative measurement instrument, the Effectiveness of Treatment
Apnea-Hypopnea Index (ET-AHI). The ET-AHI is a weighted, composite
measurement of the AHI both during adherence and non-adherence
with CPAP therapy. ET-AHI = (CPAP Treatment AHI x % adherence to
therapy) + (Untreated AHI x % non-adherence to therapy).
Methods: We retrospectively evaluated 37 adult (mean age = 44.2 ±
9.0 years) patients with moderate to severe OSA (baseline AHI = 56.3 ±
22.6), who subsequently underwent CPAP Titration (AHI = 4.3 ± 5.9).
SLEEP, Volume 34, Abstract Supplement, 2011
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