High Blood Pressure - Diagnosis - Diagnosis
Your doctor may diagnose you with high blood pressure based on your medical history and if your blood pressure readings are consistently at high levels. Your doctor may do more tests to look for medical conditions that could cause high blood pressure, or to see if high blood pressure has affected your kidneys.
Medical history
Your doctor will want to understand your risk factors and get general information about your health—such as your eating patterns, your physical activity level, and your family’s health history to develop a treatment plan for you. Your doctor also will ask questions to see if high blood pressure has caused you any health problems. This will help your doctor determine if you need to undergo any tests.
Confirming high blood pressure
To diagnose high blood pressure, your doctor will take two or more readings at separate medical appointments. Learn more about screening for high blood pressure, including how to take it yourself.
For most adults, a normal blood pressure is less than 120/80 mm Hg. Your doctor may diagnose you with high blood pressure when you have consistent systolic readings of 130 mm Hg or higher or diastolic readings of 80 mm Hg or higher.
Blood Pressure Levels
|
Classification |
Systolic and diastolic readings |
|
Normal |
systolic: less than 120 mm Hg |
|
Elevated |
systolic: 120–129 mm Hg |
|
High blood pressure |
systolic: 130 mm Hg or higher |
For children younger than 13, blood pressure readings are compared with readings common for children of the same, age, sex, and height. Read more about blood pressure readings for children.
Talk to your doctor if your blood pressure readings are consistently at or above 130/80 mm Hg. Note that readings above 180/120 mm Hg are dangerously high and require immediate medical attention.
Even after taking these steps, your blood pressure reading may not be accurate for other reasons.
- You are excited or nervous. “White coat hypertension” refers to blood pressure readings that are higher in a doctor’s office than readings at home or in a pharmacy, for example. Doctors can detect this type of high blood pressure by reviewing readings from the office and from other places.
- Your blood pressure tends to be lower when measured at the doctor’s office. This is called masked high blood pressure. Doctors can diagnose this type of high blood pressure by looking at readings taken at the office and at home, especially at night. When this happens, your doctor will have difficulty detecting high blood pressure.
- The wrong blood pressure cuff was used. Your readings can appear different if the cuff is too small or too large. It is important for your healthcare team to track your readings over time and ensure the correct pressure cuff is used for your sex and age.
- Get tips on how to prepare for a blood pressure test.
Diagnostic tests
- Blood tests. Your doctor may recommend blood tests to check for kidney damage, high cholesterol or diabetes that may raise your risk of coronary heart disease, or other problems like thyroid disease that may be causing high blood pressure.
- Blood pressure monitor. To gather more information about your blood pressure, your doctor may recommend wearing a blood pressure monitor to record readings over 24 hours. Your doctor may also teach you how to take blood pressure readings at home.