This video explains a simple at-home test, the ankle brachial index (ABI) test, to assess the possibility of arterial plaque buildup. The speaker discusses the test's accuracy and sensitivity, emphasizing it's not a replacement for professional medical diagnosis.
The two caveats mentioned are:
The 98% specificity and 90% sensitivity are only true if a person has 50% or greater blockage. The numbers are likely lower for detecting smaller amounts of plaque.
The reported numbers are based on experts performing the test, not individuals self-administering it. People with diabetes also tend to have lower specificity.
According to the video:
0.9 - 1.4: These values are considered fine.
0.8 - 0.89: This range suggests a need to focus on reducing cardiovascular disease risks.
0.6 - 0.89: There is a possibility of plaque buildup.
Below 0.6: This indicates a high likelihood of plaque buildup.
The video describes the process as follows:
Rest: Rest for 5 minutes before beginning the test to allow blood pressure to stabilize. Avoid stimulants like caffeine beforehand.
Equipment: Gather a blood pressure cuff, pen, paper, and a comfortable place to lie down.
Measurements: Take blood pressure readings in the following order: left arm, left ankle, right arm, right ankle. Record both systolic and diastolic readings for each. The video shows the speaker using an electronic blood pressure monitor; a manual cuff could also be used.
Calculation: Cross out the diastolic readings (bottom numbers). Use the highest systolic reading (top number) from your ankle measurements and divide it by the highest systolic reading from your arm measurements. This gives your ABI value.
Interpretation: Interpret your ABI value based on the ranges described previously (0.9-1.4 is fine, 0.8-0.89 warrants attention to risk factors, etc.).