You can prepare for the day, but don't eat breakfast or take medications before measuring your blood pressure. If you exercise after waking, take your blood pressure before exercising. Avoid food, caffeine, tobacco and alcohol for 30 minutes before taking a reading.
Do not smoke, exercise or use caffeine for 30 minutes to an hour before the test. Such activities increase blood pressure and heart rate. Wear a short-sleeved shirt so that the blood pressure cuff can be placed more easily around your arm. Relax in a chair for at least five minutes before the test.
Blood pressure has a daily pattern. Usually, blood pressure starts to rise a few hours before a person wakes up. It continues to rise during the day, peaking in midday. Blood pressure typically drops in the late afternoon and evening.
Blood Pressure Cuff Placement
If the cuff is too small, it can add 2 to 10 points to your bp measurement. Be sure to roll up your sleeve for a blood pressure test and also let your doctor know if the cuff feels too tight around your arm.
Blood pressure changes throughout the day. Your blood pressure is typically at its lowest right after waking up. It tends to vary by up to 30% across the day. This is because of hormone changes, activity level, and eating.
For 30% of them, the systolic pressure—the first number of a blood pressure reading—was 5 mm Hg or more different from the office reference measurement. The diastolic pressure (second number) was similarly inaccurate. "In one patient, the pressure was off by 21 mm Hg," Dr. Hiremath says.
Your first blood pressure reading will almost always be higher than the second due to a wide range of factors, both environmental and psychological. These factors include white coat syndrome, stress, and having a full bladder.
Acute meal ingestion, caffeine or nicotine use can all negatively affect BP readings, leading to errors in measurement accuracy. If the patient has a full bladder, that can lead to an error in systolic BP of between 4 mm Hg and 33 mm Hg, compared with the white-coat effect can have an error of up to 26 mm Hg.
The sensitivity for the detection of hypertension was 90.6% when BP was measured only at right arm, and 83.4% when measured only at left arm. Corresponding sensitivity were 87.9% and 87.1% in men, and 95.4% and 76.9% in women.
Something as simple as keeping yourself hydrated by drinking six to eight glasses of water every day improves blood pressure. Water makes up 73% of the human heart,¹ so no other liquid is better at controlling blood pressure.
Call 911 or emergency medical services if your blood pressure is 180/120 mm Hg or greater and you have chest pain, shortness of breath, or symptoms of stroke. Stroke symptoms include numbness or tingling, trouble speaking, or changes in vision.
While both numbers in a blood pressure reading are essential for diagnosing and treating high blood pressure, doctors primarily focus on the top number, also known as systolic pressure.
Arm position
Dependency of the arm below heart level leads to an overestimation of systolic and diastolic pressures and raising the arm above heart level leads to underestimation. The magnitude of this error can be as great as 10 mm Hg for systolic and diastolic pressures.
Your blood pressure should be checked in the morning, about an hour after you wake up, and in the evening, about an hour before you go to sleep, using the same arm each time. Taking 3 consecutive measurements (about 1 minute apart) will provide a more accurate understanding of your "true" blood pressure.
Everyone's blood pressure rises and falls many times during the course of a single day, sometimes even within minutes. Many factors contribute to these changes, including physical activity, emotion, body position, diet (especially salt and alcohol intake), and sleep deprivation.
Systolic pressure (the first number in a blood pressure reading) measures the force with which the heart pumps blood into the arteries. Diastolic pressure (the second, lower number) reflects the pressure in the arteries when the heart rests between beats.
Walking lowers systolic blood pressure by 4.11 mm Hg (95% CI, 3.01 to 5.22 mm Hg). It lowers diastolic blood pressure by 1.79 mm Hg (95% CI, 1.07 to 2.51 mm Hg) and resting heart rate by 2.76 beats per minute (bpm; 95% CI, 0.95 to 4.57 bpm).