Obstructive Sleep Apnea
Conditions
Keywords
Obstructive sleep apnea, correlation, AHI, symptoms, mechanisms
Brief summary
The purpose of this study is to investigate the correlation between health outcomes associated with the severity of obstructive sleep apnea (OSA) symptomatology, the findings will guide the design of interventional studies.
Detailed description
Obstructive sleep apnea is a condition characterised by periods of narrowing of the pharyngeal airways during sleep causing hypoxic and hypercapnic episodes with the cessation of ventilation. Considering the high number of overweight and obese individuals in Western society the understanding of the pathomechanisms behind OSA are important. This observational study aims to investigate the correlations between the severity of Obstructive Sleep Apnea assessed by the apnea-hypopnea index (AHI) and different health outcomes associated with the OSA.
Interventions
None listed
Sponsors
Bangor University
Study design
Observational model
CASE_ONLY
Time perspective
CROSS_SECTIONAL
Eligibility
Sex/Gender
MALE
Age
18 Years to 70 Years
Healthy volunteers
No
Inclusion criteria
* Body Mass Index ≤39 * Not received any treatment for Obstructive Sleep Apnea. * Is a non-smoker * Is not epileptic * Epworth Sleepiness Scale ≥ 10. * Patient's on Statins or antihypertensive drugs are included as so frequent in OSA.
Exclusion criteria
* Body Mass Index ≥ 39. * Presence of significant or unstable Renal, Liver or Heart Failure. * Receiving anti-diabetic treatment. * Is a smoker. * Is epileptic * Presence of significant or unstable psychological morbidities.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Apnea-Hypopnea Index (AHI) | one night within four weeks of study. | AHI refers to how is the number of apneas and hypopneas per an hour of sleep. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Functional residual volume | Within four weeks of recruitment prior to CPAP treatment | Air present in lungs at the end of passive expiration |
| Total lung capacity | Within four weeks of recruitment prior to CPAP treatment | Total volume of lungs |
| Forced Vital capacity | Within four weeks of recruitment prior to CPAP treatment | Maximum amount of air which can be expired from the lungs following a full inspiration |
| Forced expiratory volume in one second (FEV1) | Within four weeks of recruitment prior to CPAP treatment | Maximum amount of air which can be expired from the lungs in one second. |
| Airway Resistance | Within four weeks of recruitment prior to CPAP treatment | Opposition of flow caused by forces of friction. |
| Plasma 2-arachidonoylglycerol (2-AG) | Within four weeks of recruitment prior to CPAP treatment and after four weeks of CPAP treatment. | Ligand of the G-protein coupled CB1 and CB2 receptors, has been found to be correlated with Oleylethanolamide (OEA) in OSA patients have various effects on energy metabolism. |
| Plasma Anandamide (ANA) | Within four weeks of recruitment prior to CPAP treatment and after four weeks of CPAP treatment | Ligand of the G-protein coupled CB1 and CB2 receptors, found to be correlated with blood pressure in OSA after the adjustment of confounding variables. Have various effects on energy metabolism. |
| Plasma oleoylethanolamine (OEA) | Within four weeks of recruitment prior to CPAP treatment and after four weeks of CPAP treatment | A lipid mediator which acts as an anorexigenic (appetite suppressant), and is elevated with sleep deprivation. |
| Plasma Leptin | Within four weeks of recruitment prior to CPAP treatment and after four weeks of CPAP treatment | Circulating protein produced in adipose tissue. Elevated in OSA and obesity. Leptin may reduce respiratory depression. |
| Plasma Adiponectin | Within four weeks of recruitment prior to CPAP treatment and after four weeks of CPAP treatment | Hormone secreted by adipocytes (Fat cells). Adiponectin is closely linked to metabolism and may have anti-inflammatory properties. |
| Plasma C-reactive Protein | Within four weeks of recruitment prior to CPAP treatment and after four weeks of CPAP treatment | Marker of inflammation. |
| Insulin | Within four weeks of recruitment prior to CPAP treatment and after four weeks of CPAP treatment | Hormone which causes liver and muscle and fat cells to take up glucose to convert to glycogen. OSA is associated with insulin resistance. |
| Neck circumference | Within four weeks of recruitment prior to CPAP treatment | — |
| Waist circumference | Within four weeks of recruitment prior to CPAP treatment | — |
| Hip circumference | Within four weeks of recruitment prior to CPAP treatment | — |
| Weight | Within four weeks of recruitment prior to CPAP treatment | — |
| Residual volume | Within four weeks of recruitment prior to CPAP treatment | Volume of air remaining in lungs after full expiration |
| Fat mass | Within four weeks of recruitment prior to CPAP treatment | Fat components of the human body estimated non-invasively using bioimpedance measurement system. |
| Maximal Inspiratory pressure | Within four weeks of recruitment prior to CPAP treatment | Measured at residual volume, reflects the strength of the diaphragm and other inspiratory muscles. |
| Rate of inspiratory muscle fatigue | Within four weeks of recruitment prior to CPAP treatment | The decline in maximal inspiratory pressure following inspiration against a resistance. |
| Chest RPE | Within four weeks of recruitment prior to CPAP treatment | Rating of perceived exertion in the chest and associated airways during the inspiratory fatigue protocol. |
| Dyspnea | Within four weeks of recruitment prior to CPAP treatment | Rating of breathlessness half way through fatigue protocol and at the end of protocol. |
| Ventilation with 25% O2/ 6% CO2 | Within four weeks of recruitment prior to CPAP treatment | Measures the breathing response to high oxygen and high CO2 therefore assessing the central chemoreceptors response only. |
| Ventilation with 13% O2 | Within four weeks of recruitment prior to CPAP treatment | Measures the breathing response to low oxygen. Designed to Assess the response to the peripheral chemoreceptors. |
| Ventilation with 13% O2 / 6% CO2 | Within four weeks of recruitment prior to CPAP treatment | Measures the breathing response to low oxygen and high CO2. Designed to assess the response of the sum of the peripheral and central chemoreceptors |
| Mean RR interval | Within four weeks of recruitment prior to CPAP treatment | Time domain measure: Average time interval between the heart beats R waves |
| SDNN | Within four weeks of recruitment prior to CPAP treatment | Time domain measure: The standard deviation of all RR intervals |
| NN50 count | Within four weeks of recruitment prior to CPAP treatment | Time domain measure: The number of pairs of adjacent RR intervals differing by more than 50 ms in the entire analysis interval. |
| NN50 of total HR (%) | Within four weeks of recruitment prior to CPAP treatment | Time domain measure: NN50 count divided by total number of all RR intervals. |
| HRV triangular index | Within four weeks of recruitment prior to CPAP treatment | The total number of RR intervals divided by maximum height of the histogram excluding boundaries. |
| Low frequency domain | Within four weeks of recruitment prior to CPAP treatment. | Frequency domain analysis: represents 0.04-0.15 Hz reflecting sympathetic activity. |
| High frequency domain | Within four weeks of recruitment prior to CPAP treatment. | Frequency domain analysis: represents 0.15-0.40 Hz reflecting parasympathetic activity. |
| LF/HF ratio | Within four weeks of recruitment prior to CPAP treatment. | The ratio of low frequency (0.04 - 0.15 Hz) to high (0.15-0.40 Hz) frequency recordings. |
| Fat-free mass | Within four weeks of recruitment prior to CPAP treatment | Non-fat components of the human body estimated non-invasively using a bioimpedance measurement system. |
Countries
United Kingdom
Outcome results
None listed