Pathophysiology of the Upper Airway in Patients With COPD and Concomitant OSA
- Conditions
- Obstructive Sleep Apnea
- Interventions
- Other: Sleep and pulmonary physiologic measurements
- Registration Number
- NCT02567448
- Lead Sponsor
- University of California, San Diego
- Brief Summary
The purpose of study is to evaluate the physiologic effects of pulmonary tissue/structural changes associated with COPD and upper airway inflammation on upper airway collapsibility. Upper airway collapsibility is closely associated with development of obstructive sleep apnea (OSA), which is a common disease characterized by repetitive collapse of upper airway during sleep, leading to hypoxemia and arousal. OSA has important neurocognitive and cardiovascular consequences, especially in patients with COPD.
Participants in this research study will undergo two overnight sleep studies (PSGs), pulmonary function test, and CT scan of the upper airway and chest. The first sleep study will evaluate the sleep breathing disorder and the second sleep study will measure the upper airway collapsibility, called critical closing pressure (Pcrit). Pcrit is measured by a modified continuous positive airway pressure (CPAP) machine which can provide a wide range of pressures between 20 and -20 cmH2O in order to modify upper airway pressure.
- Detailed Description
This is a physiologic study to assess the effects of lower airway and lung tissue changes of COPD on upper airway collapsibility. Increased in lung volume and destruction of alveolar wall in COPD may have opposite and various effects on the upper airway collapsibility, which is an important factor of OSA development.
Chronic obstructive pulmonary disease (COPD) and obstructive sleep apnea (OSA) are very common disorders associated with considerable morbidity, mortality, and healthcare costs. The prevalence of both co-existing conditions is estimated to be \~4% of the general population. This COPD-OSA "overlap" syndrome causes more severe hypoxemia than either COPD or OSA alone and has important clinical consequences, including death. COPD is usually excluded in OSA research and OSA is typically excluded or not assessed in studies of COPD; thus, available information about the "overlap" syndrome is limited. Therefore, it is important to identify patients with both COPD and OSA and determine the mechanisms of poor outcomes for these patients in order to optimize therapy. The pathophysiology of the COPD-OSA syndrome is not well understood. The investigators propose to investigate upper airway (UA) anatomic characteristics and collapsibility as potential underlying mechanisms that may help to explain the negative additive effect of having both conditions. The objectives are to study CT measures of airway anatomy and the critical closing pressure of the upper airway (Pcrit), a gold standard measure of upper airway collapsibility, in patients with COPD-OSA compared with COPD only and normal controls. CT scan of upper airway and chest will allow precise measures of upper airway characteristics and COPD associated alveolar and lower airway ch. angesMeasures of upper airway collapsibility will provide us information about the mechanical nature of the airway and if the patients are more likely to have OSA. Subjects with COPD-OSA may exhibit more upper airway inflammation possibly due to their pre-existing COPD disease and the reoccurring opening and closing of the upper airway due to the OSA. Therefore the investigators would like to assess the degree of inflammation in these patients compared to normal controls.
Recruitment & Eligibility
- Status
- TERMINATED
- Sex
- All
- Target Recruitment
- 24
Not provided
Not provided
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- PARALLEL
- Arm && Interventions
Group Intervention Description Normal Control Group Sleep and pulmonary physiologic measurements Patients who are healthy, without major medical or sleep problems, and have normal spirometry. All patients will have sleep and pulmonary physiologic measurements. COPD Group Sleep and pulmonary physiologic measurements Patients who were previously diagnosed of moderate to severe COPD as determined by spirometry. All patients will have sleep and pulmonary physiologic measurements.
- Primary Outcome Measures
Name Time Method Critical closing pressure (PCrit) Baseline Measured during overnight sleep study
- Secondary Outcome Measures
Name Time Method Parapharyngeal fat pad volume Baseline Emphysema distribution Baseline Measured from CT chest scan
Width of hard palate Baseline Measured from upper airway CT scan
Upper airway length Baseline Measured from upper airway CT scan
Nasophayngeal/retropalatal/retroglossal pharyngeal cavity volume Baseline Measured from upper airway CT scan
Tongue volume Baseline Lower airway wall thickness on chest CT scan Baseline Measured from CT chest scan
Forced expiratory volume in 1 second (FEV1) Baseline Emphysema score Baseline Measured from CT chest scan
Anteroposterior airway dimension on hard palate/uvula/epiglottis level Baseline Measured from upper airway CT scan
Lateral airway dimension on hard palate/uvula/epiglottis level Baseline Measured from upper airway CT scan
Cross-sectional airway area on hard palate/uvula/epiglottis level Baseline Measured from upper airway CT scan
Distance between the lower edge of the mandible and the lower edge of the hyoid (MH) Baseline Measured from upper airway CT scan
Volume of retropalatal/retroglossal soft tissue Baseline Pharyngeal lavage cell count distribution Baseline Minimal later airway dimension (mLAT) Baseline Measured from upper airway CT scan
Minimal anteroposterior airway dimension (mAP) Baseline Measured from upper airway CT scan
Minimal cross sectional airway area (mCSA) Baseline Measured from upper airway CT scan
Volume within the cervico-mandibular bony frame Baseline Measured from upper airway CT scan
Total lung capacity (TLC) Baseline Ratio of residual volume / total lung capacity (RV/TLC) Baseline Diffusing capacity of the lung for carbon monoxide (DLCO) Baseline
Trial Locations
- Locations (1)
University of California, San Diego
🇺🇸San Diego, California, United States