Another benefit of the scan is more valid measurements of dual-arm and ankle-brachial blood pressures. Since subjects remain prone and relaxed for the approximate 15- to 20-minute scan time, the measurements are truly “resting” blood pressures and heartrate measures. To achieve test-retest reliability, the ankle brachial pressure index (APBI) is obtained immediately after the DEXA scan is complete, while the subject is still lying down on the table.
The (ABPI) is obtained by taking a resting blood pressure measurement of the subject’s upper arm and another measurement just above the ankle. The ABPI is the ratio of the blood pressure in the ankle to the blood pressure in the arms. It is calculated by dividing the systolic blood pressure at each site to provide a measure of the health of the blood circulatory system.