3. Diagnosis of Hypertension
Blood pressure measurement
To measure your blood pressure, your doctor or a specialist will usually place an inflatable arm cuff around your arm and measure your blood pressure using a pressure-measuring gauge.
A blood pressure reading, given in millimetres of mercury (mm Hg), has two numbers. The first or upper number measures the pressure in your arteries when your heart beats (systolic pressure). The second, or lower, number measures the pressure in your arteries between beats (diastolic pressure).
Categories of blood pressure measurement
• Normal blood pressure: Your blood pressure is normal if it’s below 120/80 mm Hg.
• Elevated blood pressure: this is a systolic pressure ranging from 120 to 129 mm Hg and a diastolic pressure below 80 mm Hg. Elevated blood pressure tends to get worse over time unless steps are taken to control blood pressure.
• Stage 1 hypertension:this is a systolic pressure ranging from 130 to 139 mm Hg or a diastolic pressure ranging from 80 to 89 mm Hg.
• Stage 2 hypertension: this is a more severe hypertension. Stage 2 hypertension is a systolic pressure of 140 mm Hg or higher or a diastolic pressure of 90 mm Hg or higher.
Both numbers in a blood pressure reading are important. But after age 50, the systolic reading is even more significant.
Isolated systolic hypertension is a condition in which the diastolic pressure is normal (less than 80 mm Hg) but systolic pressure is high (greater than or equal to 130 mm Hg). This is a common type of high blood pressure among people older than 65.
Your doctor will likely take two to three blood pressure readings each at three or more separate appointments before diagnosing you with high blood pressure. This is because blood pressure normally varies throughout the day, and it may be elevated during visits to the doctor (white coat hypertension).
Your blood pressure generally should be measured in both arms to determine if there is a difference. It’s important to use an appropriate-sized arm cuff.
Your doctor may ask you to record your blood pressure at home to provide additional information and confirm if you have high blood pressure.
A 24-hour blood pressure monitoring test called ambulatory blood pressure monitoring may be recommended by your doctor to confirm if you have high blood pressure. The device used for this test measures your blood pressure at regular intervals over a 24-hour period and provides a more accurate picture of blood pressure changes over an average day and night.
Medical history/physical examination
If you have any type of high blood pressure, your doctor will review your medical history and conduct a physical examination.
Your doctor may also recommend routine tests such as:
• Urine test (urinalysis)
• blood tests
• cholesterol test
• electrocardiogram — a test that measures your heart’s electrical activity.
• Echocardiogram to check for more signs of heart disease