Continuous Positive Airway Pressure and Breathlessness in Obese Patients with Obstructive Sleep Apnea: A Pilot Study

TY - JOUR

T1 - Continuous Positive Airway Pressure and Breathlessness in Obese Patients with Obstructive Sleep Apnea

T2 - A Pilot Study

AU - Xiao, Sichang

AU - Bastianpillai, Johan

AU - Ratneswaran, Culadeeban

AU - Pengo, Martino F

AU - Luo, Yuanming

AU - Jolley, Caroline J.

AU - Moxham, John

AU - Steier, Joerg

N1 - Copyright © 2016 Associated Professional Sleep Societies, LLC. All rights reserved.

PY - 2016/6/1

Y1 - 2016/6/1

N2 - STUDY OBJECTIVES: Continuous positive airway pressure (CPAP) is an effective treatment for obstructive sleep apnea (OSA). However, long-term compliance with CPAP is limited. We tested the hypothesis that CPAP levels routinely used during sleep increase neural respiratory drive (NRD) and breathlessness, which may discourage compliance.METHODS: This was an observational physiological cohort study in a respiratory physiology and sleep unit, University Hospital. Patients with a body mass index (BMI) >25 kg/m2 and confirmed OSA were studied supine and awake on CPAP (4-20 cm H2O, increments of 2 cm H2O/3 min). We measured NRD during awake CPAP titration in obese subjects to quantify the response to the load of the respiratory system and compared it to the CPAP used for nocturnal treatment, with the modified Borg Scale (mBorg) for dyspnea recorded (from 0 to 10 points, with higher numbers indicating more breathlessness).RESULTS: Fifteen patients (age 48±10 years, 12 male, BMI 38.9±5.8 kg/m2) with OSA (AHI 32.2±21.1/h, 95th percentile of CPAP 14.1±3.8 cm H2O) were studied and NRD (electromyogram of the parasternal intercostals, EMGpara; EMG of the external oblique, EMGabdomen) was recorded (awake, supine). Awake, EMGpara declined from baseline to 70.2%±17.1% when CPAP of 10.7±3.4 cm H2O (P = 0.026) was applied. Further increase in CPAP led to a rise in EMGpara and increased breathlessness (P = 0.02). CPAP compliance (nights used) correlated negatively with mBorg scores (r = -0.738, P = 0.006).CONCLUSIONS: Awake, the respiratory system is maximally offloaded with lower than therapeutic CPAP levels in obese patients with OSA. Levels of NRD observed at effective CPAP levels while asleep are associated with breathlessness which may limit long-term CPAP compliance.

AB - STUDY OBJECTIVES: Continuous positive airway pressure (CPAP) is an effective treatment for obstructive sleep apnea (OSA). However, long-term compliance with CPAP is limited. We tested the hypothesis that CPAP levels routinely used during sleep increase neural respiratory drive (NRD) and breathlessness, which may discourage compliance.METHODS: This was an observational physiological cohort study in a respiratory physiology and sleep unit, University Hospital. Patients with a body mass index (BMI) >25 kg/m2 and confirmed OSA were studied supine and awake on CPAP (4-20 cm H2O, increments of 2 cm H2O/3 min). We measured NRD during awake CPAP titration in obese subjects to quantify the response to the load of the respiratory system and compared it to the CPAP used for nocturnal treatment, with the modified Borg Scale (mBorg) for dyspnea recorded (from 0 to 10 points, with higher numbers indicating more breathlessness).RESULTS: Fifteen patients (age 48±10 years, 12 male, BMI 38.9±5.8 kg/m2) with OSA (AHI 32.2±21.1/h, 95th percentile of CPAP 14.1±3.8 cm H2O) were studied and NRD (electromyogram of the parasternal intercostals, EMGpara; EMG of the external oblique, EMGabdomen) was recorded (awake, supine). Awake, EMGpara declined from baseline to 70.2%±17.1% when CPAP of 10.7±3.4 cm H2O (P = 0.026) was applied. Further increase in CPAP led to a rise in EMGpara and increased breathlessness (P = 0.02). CPAP compliance (nights used) correlated negatively with mBorg scores (r = -0.738, P = 0.006).CONCLUSIONS: Awake, the respiratory system is maximally offloaded with lower than therapeutic CPAP levels in obese patients with OSA. Levels of NRD observed at effective CPAP levels while asleep are associated with breathlessness which may limit long-term CPAP compliance.

U2 - 10.5665/sleep.5832

DO - 10.5665/sleep.5832

M3 - Article

C2 - 27091534

SN - 0161-8105

VL - 39

SP - 1201

EP - 1210

JO - Sleep

JF - Sleep

IS - 6

ER -