None listed
Conditions
Brief summary
Increasing evidence suggests that sleep apnoea is an important factor driving CVD risk. Beyond worsening blood pressure and diabetes, sleep apnoea has direct adverse effects on blood vessels. In this study, we propose to employ a molecular imaging approach to investigate the impact of OSA on plaque activity. This study is a cross-sectional, observational study with the objective to ascertain the presence and extent of inflammatory activity of atherosclerotic plaque in patients with sleep apnoea. We will enroll 50 adults with obstructive sleep apnoea (OSA), 25 with mild OSA and 25 with moderate to severe OSA commencing continuous positive airways pressure (CPAP) therapy with either established atherosclerotic cardiovascular disease (ASCVD) or risk factors for ASCVD. A combined computed tomography (CT) and positron emission tomography (PET) scan will be performed following intravenous administration of is 18F-fluorodeoxyglucose (18F-FDG) which will enable measurement of inflammatory plaque activity. The findings will provide important information that may lead to the development of an important new marker to monitor reductions in CVD risk in sleep apnoea.
Interventions
Patients with moderate to severe (based on a clinically indicated PSG) OSA: (AHI greater than 15) and either high symptom load (ESS greater than 10 or self-reported falling asleep accident/near miss accident in the last 6 months) or resistant hypertension (elevated BP despite at least 3 agents) requiring CPAP will participate in this study. A PET-CT will be performed following intravenous administration of 18F-fluorodeoxyglucose (FDG) on the PET-CT scanner at the Clinical Research Imaging Centre
Patients with moderate to severe (based on a clinically indicated PSG) OSA: (AHI greater than 15) and either high symptom load (ESS greater than 10 or self-reported falling asleep accident/near miss accident in the last 6 months) or resistant hypertension (elevated BP despite at least 3 agents) requiring CPAP will participate in this study. A PET-CT will be performed following intravenous administration of 18F-fluorodeoxyglucose (FDG) on the PET-CT scanner at the Clinical Research Imaging Centre (CRIC), which is capable of vascular imaging of the aorta and carotid arteries. Patients will be asked not to participate in any vigorous exercise 24 hours prior to study, and to fast between 6 and 8 hours before being scanned. Blood glucose will be checked by finger-stick measurement before 18F-FDG injections. Patients with a pre-scan glucose level not within 2.5-10mmol/L will be excluded from the study. 18F-FDG (5 MBq/kg) will be injected intravenously, and patients will rest for 90 minutes prior to scan. Scan will take about 60 minutes.
Sponsors
South Australian Health and Medical Research Institute (SAHMRI)
Eligibility
Sex/Gender
All
Age
40 Years to No maximum
Healthy volunteers
No
Inclusion criteria
a. Able to provide written, informed consent b. Age greater than or equal to 40 years of age c. Evidence of established atherosclerotic cardiovascular disease As evident by i. History of myocardial infarction ii. acute coronary syndrome iii. arterial revascularization OR Risk Factor (One Required) i. Cigarette smoking current? ii. Hypertension (BP greater than or equal to 140/90 mm Hg or current use of antihypertensive medication)? iii. Diabetes mellitus iv. Low HDL cholesterol (men less than 1.0 mmol/l; women less than 1.3 mmol/l) v. Family history of premature CHD (in first-degree male relative less than 55 years of age; in first-degree female relative less than 65 years of age vi. Age (men: 50 years or older; women: 55 years or older)? vii. hs-CRP greater than or equal to 2 mg/L d. OSA diagnosed by polysomnography (PSG) with diagnosis that fits one of the two options below I. AHI greater than 15 and either high symptom load (ESS greater than 10 or self-reported falling asleep accident/near miss accident in the last 6 months) or resistant hypertension (elevated BP despite at least 3 agents) requiring CPAP II. AHI less than 15 not requiring CPAP and both minimal symptoms (ESS less than 10 and no self-reported falling asleep accident/near miss accident in the last 6 months) and lack of resistant hypertension e. Treated with a stable dose of statin therapy for 4 weeks or more (dose can be zero)
Exclusion criteria
a. Inability to provide written, informed consent b. Unwilling to undergo PET-CT imaging c. Treated with chronic anti-inflammatory agents (immunosuppressants, oral corticosteroids) d. Chronic kidney disease (use of dialysis or eGRF <50 mL/min) e. Subjects with uncontrolled diabetes defined as HbA1c > 13 % in the last 3 months f. insulin treatment for diabetes mellitus g. Systemic inflammatory or autoimmune disease h. Prior aortic or carotid surgery i. Prior use of CPAP for OSA in the last 12 months j. Female participants cannot be pregnant or breast-feeding
Outcome results
None listed