The American Heart Association (AHA) encourages everyone to “know his or her numbers”. One of the numbers that the AHA wants us to know is the blood pressure. The AHA recommends that the blood pressure be kept under 120/80. Is that the right number? Is that the right level for blood pressure for everyone? If not, what is the “right” number for the blood pressure?
For those without established high blood pressure (hypertension), yearly blood pressure checks are recommended. If the blood pressure is over 140/90 on three separate occasions, weeks apart, in a person who is not currently ill, then hypertension is diagnosed and treatment for high blood pressure is started. It is very important to measure the blood pressure correctly. Often, the blood pressure is elevated in the doctor’s office (called “white coat hypertension”) and checking the blood pressure at home is advised. To do this properly, one must sit quietly for 15 minutes, with the arm in a relaxed state, propped on a table or armchair and at the level of the heart. It is recommended that two to three blood pressure measurements be obtained and averaged to determine a true number.
For those with established hypertension, two trials and some recent expert opinions are important to know. The SPRINT trial split 9000 hypertensive patients into two groups; one group was treated to a blood pressure under 120, the other to under 140. The under 120 group had less heart failure and deaths due to heart disease. The trial concluded that hypertensive patients be treated to a blood pressure under 120. However this conclusion has not yet been universally accepted due to several factors. The under 120 group was taking more medications (an average of 3 meds versus 2 for the 140 group) and had more side effects from medications (falling, low blood pressure and kidney problems). In addition, the method used to measure blood pressure was very vigorous and may not be representative of blood pressure measurements in the real world. Lastly, SPRINT did not include diabetic patients.
The ACCORD trial was designed for the diabetic hypertensive patient. This trial split 4000 patients into two groups as well: one group’s blood pressure was treated to under 120, the other to under 140. The theory was that diabetic patients are at high risk for heart disease and that treating aggressively (to under 120) would be better. In fact, the trial found no difference between the groups. It concluded that diabetic patients should be treated to under 140, as the more aggressive target didn’t add any benefit.
What is the blood pressure target for the older hypertensive patient? In 2014, the Joint National Commission changed the blood pressure goal from under 140 to under 150 for those over 60 years old. In January 2017, the American College of Physicians published an expert opinion document agreeing with treating patients older than 60 to under 150. However, an analysis of patients in the SPRINT trial who were over 60 years old showed that they too had less cardiac problems when treated to under 120 compared those treated to under 140. Lastly, in February 2017, a trial following 10,000 older hypertensive patients showed that treating to a blood pressure less than 140 decreased the risk for major cardiac events and deaths.
So, what is the right blood pressure number for the hypertensive patient? Clearly there is no single best number for all patients. There is a lot of disagreement on the blood pressure target between trials and between experts. For now, the best guidelines are the following. Diabetic hypertensive patients should be treated to a blood pressure under 140. Nondiabetic hypertensive patients under age 60 should be under 140 and those who are younger (around 50 years old) or with other significant risk factors for heart disease should be treated to a blood pressure under 120. Nondiabetic patients older than 60 years old, definitely should be treated to under 150 and possibly under 140. As all blood pressure medications work and all have their side effects, the best way to manage high blood pressure is for the doctor and the patient to work together. The doctor should try to get the patient’s blood pressure to a proper goal while simplifying the medication regimen (taking meds once or twice per day) and minimizing the side effects. The patient should faithfully take medications, check the blood pressure at home, report side effects and follow agreed upon life style modifications. The best blood pressure treatment requires constant collaboration and negotiation between the doctor and the patient.