New guidelines were recently issued by the American College of Cardiology and the American Heart Association regarding ideal blood pressure values in adults. The guidelines were revised from the previous ones after a panel of 21 experts reviewed more than 900 studies.
The new guidelines are as follows:
BP < 120/80 is normal
BP 120-129/<80 is considered elevated
BP 130-139 systolic or 80-89 diastolic is Stage 1 hypertension
BP 140-159 systolic or 90-99 diastolic is Stage 2 hypertension
BP >160 systolic and >100 diastolic is Stage 2 hypertension
BP >180 systolic and >120 diastolic is considered a hypertensive crisis and demands immediate treatment.
The scientists emphasized the accuracy of BP measurements, and the importance of considering an average of several BP’s taken at several visits. They also emphasized at-home blood pressure monitoring.
These new definitions will categorize almost half of the US adult population as having hypertension, and more than 80% of those over the age of 80 will fall into the hypertensive range.
Not all of those with the new diagnosis of hypertension will need medication as treatment.
The physician takes into account a person’s cardiovascular risk factors as can be determined by several algorithms. A person already diagnosed with heart disease should always be treated, as well as anyone over the age of 65.
The primary treatment for hypertension for those with a lower risk is considered lifestyle modifications. These modifications include losing weight, following the DASH diet (Dietary Approaches to Stop Hypertension), reducing salt intake to less that 1500 mg per day, while increasing potassium intake to 3500 mg per day in the diet. It is also recommended that physical exercise should be at least 30 minutes three times per week, and alcohol limited to two drinks per day or less for men and one drink per day or less for women.
Older adults who aggressively treat hypertension have demonstrated lower cardiovascular mortality and morbidity without being subjected to increased risks of hypotension and falls.
Around the age of menopause, women are less likely to be hypertensive than men, but as women age, their prevalence of hypertension is greater than men of the same age.
It used to be that medication was considered if the BP was greater than 140/90, but now the
threshold is 130/80 unless lifestyle modifications are successful. It seems that ideal BP is 115/75 or less. The reason for this change is that individuals with blood pressures above this range do show increases in cardiovascular risk, and earlier intervention can lower these risks.
An app called the ASCVD Risk Estimator (http://tools.acc.org/ASCVD-Risk-Estimator) can determine if a person’s 10 year risk of developing heart disease is greater than 10%, and therefore should be treated with medication.
More aggressive treatment of hypertension is expected to save lives by preventing coronary artery disease, strokes, and kidney failure. Reducing systolic blood pressure by just 10mm Hg will result in a 20% reduction in major cardiovascular events, with a 17% reduction in coronary artery disease, a 27% reduction in strokes, and a 28% reduction in heart failure. Mortality for all causes decreases 13%. Larger decreases in blood pressure result in even greater reductions of morbidity and mortality.
The purpose of the new guidelines should raise awareness of the importance of BP on heart disease risks, promote lifestyle modifications, and support the use of antihypertensive medication in those with higher blood pressures, or increased risk of cardiovascular disease.
P.S. In my medical practice, I encourage patients to purchase a BP monitoring device. They are inexpensive and easy to use. I ask patients to monitor their blood pressures over several weeks, taking measurements at different times of the day, and providing their primary care practitioners with a log of BP measurements. This attempt at more accurate data will hopefully help practitioners determine who will benefit from medication intervention.
Stay tuned for a future blog which will explain the DASH diet.
Marilyn C. Jerome, MD
Foxhall OB-Gyn Associates
The North American Menopause Society: First to Know, November 17, 2017.
Revised ACC/AHA guidelines categorize many more midlife women with high blood pressure.
By Howard Hodis, MD