Model hem 907xl

All studies were performed by a single registered diagnostic cardiac sonographer in participants who held vasoactive medications and were instructed not to smoke cigarettes or exercise prior to testing.^{1 (link),2 (link)} After a 15-minute supine rest, left arm brachial blood pressure was measured by oscillometric sphygmomanometry (OMRON Model HEM-907XL; Omron Healthcare Inc., Kyoto, Japan). The right BA was imaged using a linear array vascular ultrasound transducer (ACUSON Sequoia Model C512, 8L5c transducer; Siemens Medical Solutions, Malvern, PA, USA). Extra-vascular landmarks were labeled to ensure consistent imaging within and between studies over time. Overall gain, time-gain compensation settings, and contrast were the same across studies for each participant. After baseline B-mode and Doppler images were obtained, a blood pressure cuff was placed proximal to the visualized BA segment, was inflated for 4 minutes at 50 mmHg above systolic pressure, and adjusted upwards if necessary to ensure complete occlusion using a Hokanson E20 Rapid Cuff Inflation System (D.E. Hokanson Inc., Bellevue, WA, USA). After cuff release, longitudinal images of the BA and Doppler blood flow were obtained up to 90 seconds after cuff deflation.

Age, sex, race, years of education, income, and smoking status (defined as never, current, and former) were self-reported and ascertained by standardized questionnaires. Physical activity was measured using total amount of exercise in exercise units, which was calculated using reports of the amount of time per week spent in 13 categories of physical activity over the past year. Body mass index (BMI) was calculated as weight in kilograms divided by height in meters squared (kg/m²). Diabetes was defined as fasting serum glucose level ≥ 126 mg/dL or self-reported diabetes medication use in each exam year. Total cholesterol (mg/dl) was measured from fasting blood draws. BP was measured while seated using a standard automated BP measurement monitor (OMRON model HEM907XL; Omron). Additionally, participants reported their medication use, including use of diuretic medications. All the covariates were repeatedly ascertained from examinations from 1990 through 2015.