Clinical trial NCT05335083: CPAP and Glucose Metabolism in Non-Diabetic OSA Subjects
Official title: The Impact of CPAP on Glucose Metabolism in Moderate-Severe Obstructive Sleep Apnoea Patients Without Diabetes - An Observational Study
Study type: INTERVENTIONAL
Overall status: NOT_YET_RECRUITING
Phase: NA
Conditions: Obstructive Sleep Apnea
Pre-diabetes
Lead sponsor: Woolcock Institute of Medical Research
Sponsor class: OTHER
First posted: 2022-04-19
Enrollment: 100
Sex: ALL
Minimum age (years): 18
Maximum age (years): 65
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: NON_RANDOMIZED
Intervention model: SEQUENTIAL
Primary purpose: TREATMENT

Brief summary: The purpose of the current study is to investigate whether alleviation of OSA by CPAP positively impacts glucose metabolism in non-diabetic patients.

Detailed description: Glucose metabolism in patients newly diagnosed with moderate-severe OSA and without diabetes will be monitored for two weeks prior to commencement of CPAP using a CGM. They will consume a 75g oral glucose drink fasted on waking twice during the two-week monitoring period, having consumed a standardised meal the evening prior. After establishing CPAP use for at least four weeks they will undergo the same protocol as for the observation period prior to commencing CPAP. Glucose metabolism will be monitored using an interstitial (skin based) glucose monitor.

Eligibility criteria: Inclusion Criteria:

1. Community dwelling adult males and females aged 18-65 years
2. Polysomnography confirmed moderate to severe OSA with apnea hypopnea index (AHI) ≥15/hr within the past 60 months
3. Able to give written informed consent
4. Proficient in English

6. Diagnosed non-diabetic as defined by the American Diabetes Association as any of the following recent (\<3 months) findings:

1. Fasting glucose with a BGL \<7.0 mmol/L
2. Glucose tolerance with a 2-hour BGL of \< 11.1 mmol/L after a formal 75g Oral Glucose Tolerance Test (OGTT)
3. HbA1C of ≤ 6.5% 7. Possession or regular access to a mobile telephone with capability to download and run the Withings Sleep Anlayser App.

Exclusion Criteria:

1. Clinically significant co-morbidity (e.g. myocardial infarction, congestive heart failure, stroke, arrythmia, chronic kidney or liver disease, epilepsy, head injury)
2. Severe mental health disorders (e.g. current major depressive disorder, schizophrenia, bipolar disorder) that in the opinion of the investigator is not adequately treated or will significantly affect their participation in the study.
3. Regular (\>2 times per month) use of sleep-affecting medication (e.g. benzodiazepines, opioids, antidepressants)
4. Regular night shift work or travel overseas within the last 2 weeks
5. Sleep physician has advised against CPAP withdrawal
6. Pregnancy
7. Active smoking or routine alcohol use (more than 2 standard drinks a day) or excessive caffeine intake (\>300 mg a day) or recent (in the past month) use of illicit drugs
8. Current or previous diagnosis of diabetes mellitus (previous gestational diabetes mellitus not excluded)
9. Current or recent (\<3 months) use of hypoglycaemic agents
10. Undergoing a weight loss programme
11. Contraindications for use of the FreeStyle Libre Pro Sensor. E.g. Known hypersensitivity to skin adhesives such as those used to attach the sensor to the arm.

Primary outcomes:
measure: Mean 24 hour glucose difference between the CPAP on and CPAP off conditions
timeFrame: 2 weeks
Secondary outcomes:
measure: Mean daytime glucose difference between the CPAP on and CPAP off conditions
timeFrame: 2 weeks
measure: Mean night time glucose
timeFrame: 2 weeks
measure: Glucose tolerance
timeFrame: 2 weeks
measure: Coefficient of Variation
timeFrame: 2 Weeks
measure: SD of Mean Glucose
timeFrame: 2 Weeks
measure: Time in Range (TIR)
timeFrame: 2 Weeks
measure: Time Below Range (TBR)
timeFrame: 2 Weeks
measure: Time below Range <3.0 mmol/L
timeFrame: 2 Weeks
measure: Time Above Range (TAR)
timeFrame: 2 Weeks
measure: Time Above Range >13.9 mmol/L
timeFrame: 2 Weeks
measure: Time in Tight Range (TITR)
timeFrame: 2 Weeks
measure: Change in Glucose Management Indicator
timeFrame: 2 Weeks
measure: Extended hypoglycaemic event rate
timeFrame: 2 Weeks
measure: Extended hyperglycaemic event
timeFrame: 2 Weeks
measure: TIR >70%
timeFrame: 2 Weeks
measure: TIR improvement at least 5%
timeFrame: 2 Weeks
measure: TIR improvement at least 10%
timeFrame: 2 Weeks
measure: TBR <3.9 mmol/L <4%
timeFrame: 2 Weeks
measure: TBR <3.0 mmol/L <1%
timeFrame: 2 Weeks
measure: TAR >10.0 mmol/L >25%
timeFrame: 2 Weeks
measure: TAR >13.9 mmol/L <5%
timeFrame: 2 Weeks
measure: Hypoglycaemia
timeFrame: 2 Weeks
measure: Hypoglycaemia Alert Value (Level 1)
timeFrame: 2 Weeks
measure: Clinically Significant Hypoglycaemia (Level 2)
timeFrame: 2 Weeks
measure: Extended Hypoglycaemia
timeFrame: 2 Weeks
measure: High Glucose Level (Level 1)
timeFrame: 2 Weeks
measure: Very High Glucose (Level 2)
timeFrame: 2 Weeks
measure: Extended Hyperglycaemia
timeFrame: 2 Weeks
Other outcomes:
measure: TIR Improvement >10% and <0.5% increase in TBR <3.0 mmol/L
timeFrame: 2 Weeks
measure: Mean Glucose <8.6 mmol/L and <1% TBR <3.0 mmol/L
timeFrame: 2 Weeks
measure: TIR >70% and <1% TBR <3.9 mmol/L
timeFrame: 2 Weeks
measure: TIR >70% and < 1% TBR <3.0 mmol/L
timeFrame: 2 Weeks
Locations:
city: Camperdown
country: Australia
facility: Royal Prince Alfred Hospital
state: New South Wales
city: Macquarie Park
country: Australia
facility: Woolcock Institute of Medical Research
state: New South Wales
Study officials:
affiliation: Woolcock Institute of Medical Research
name: Craig L Phillips, PhD
role: PRINCIPAL_INVESTIGATOR
References: