RF Based QIMT & QAS Study on Chinese Adults

Study Overview
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Brief Summary
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This study intends to establish the normal reference values of carotid artery intima-media thickness and vascular elasticity of Chinese adults based on ultrasound radio frequency technology through a multi-center large-sample study, which provides important information for the risk prediction and prognosis evaluation of Chinese adults' cardiovascular disease.

Detailed Description
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After being informed about the study, all participants giving written informed consent will undergo a one-time examination of vascular ultrasound, including general characteristics and the target ultrasound parameters. To detect the smallest difference between adjacent age groups within the age range 18-79 (6 groups, α = 0.05, β = 0.20, Statistical Power = 0.80). Given the influence of multiple centers, the minimum sample size is 1800, the optimal sample size is 3500. The male to female ratio is 1:1. Quality Control including the pre-study training and data monitoring during the study.

Official Title
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Reference Values of Carotid Intima-media Thickness and Arterial Stiffness in Chinese Adults Based on Ultrasound Radio Frequency Signal: A Nationwide, Multicenter Study

Conditions
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Healthy, Adults, Carotid Intima-media Thickness, Vascular Stiffness, Chinese

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Aged 18-79 The blood pressure is normal: systolic blood pressure <140 mmHg, and diastolic blood pressure <90 mmHg The physical examination and electrocardiogram are normal Exclusion Criteria: Subjects with carotid intima-media thickness ≥ 1.0 mm should be excluded; Subjects with previous cardiovascular disease history and medication history should be excluded. The main diseases include coronary heart disease, congenital heart disease, heart failure, hypertension, stroke, hyperlipidemia, diabetes, aortic arteritis, etc.; Subjects with past medical history and medication history of endocrine, rheumatism, chronic respiratory disease, liver and kidney disease should be excluded; Obese subjects (BMI ≥ 28 kg/m2), professional athletes, pregnant and lactating women should be excluded; Alcohol or drug addicts and smokers who have not quit smoking should be excluded.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 79 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Intima-media thickness | millimeter, one-time measurement throughout the study | one-time measurement on the day of ultrasound examination | 
| Carotid stiffness index | =D▪ln(Ps/Pd)/ΔD, D: diastolic carotid diameter; Ps, systolic pressure; Pd, diastolic pressure; ΔD: Change of diameter in systolic. one-time measurement throughout the study | one-time measurement on the day of ultrasound examination | 
| Pulse wave velocity | m/sec,one-time measurement throughout the study | one-time measurement on the day of ultrasound examination | 
| Artery compliance coefficient | mm2kPa-1; =π▪(2▪D▪ΔD+ΔD2)/4▪ΔP; D: Diastolic diameter; ΔD: Change of diameter in systolic; ΔP, pulse pressure. one-time measurement throughout the study | one-time measurement on the day of ultrasound examination | 
| Age | years, one-time measurement throughout the study | one-time measurement on the day of ultrasound examination | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| blood pressure | mmHg, one-time measurement throughout the study | one-time measurement on the day of ultrasound examination | 
| fasting blood glucose | mmol/L, one-time measurement throughout the study | one-time measurement with 7 days before or after ultrasound examination | 
| Total cholesterol | mmol/L, one-time measurement throughout the study | one-time measurement with 7 days before or after ultrasound examination | 
| Triglycerides | mmol/L, one-time measurement throughout the study | one-time measurement with 7 days before or after ultrasound examination | 
| Height | m, one-time measurement throughout the study | one-time measurement on the day of ultrasound examination | 
| Weight | kg, one-time measurement throughout the study | one-time measurement on the day of ultrasound examination |