Understanding Blood Pressure: Definitions, Risks, and How to Optimize Yours
What is Blood Pressure and How is it Measured?
Blood pressure refers to the force that blood exerts on the walls of arteries as it is pumped from the heart throughout the body. It has two components – systolic and diastolic pressure.
Systolic pressure represents the pressure in the arteries when the heart contracts and pumps blood out into circulation. Diastolic pressure refers to the pressure as the heart relaxes between beats and refills with blood.
Blood pressure is measured in millimeters of mercury (mmHg) using an inflatable cuff placed around the upper arm. The first, higher number represents systolic pressure. The second, lower number is the diastolic measurement.
Normal blood pressure is defined as less than 120 mmHg systolic and less than 80 mmHg diastolic. Elevated blood pressure refers to readings with systolic between 120-129 and diastolic under 80 mmHg.
Guidelines Define Hypertension in 2 Stages
Hypertension, or high blood pressure, has two severity stages:
- Stage 1 is defined as 130-139 mmHg systolic or 80-89 mmHg diastolic.
- Stage 2 reflects readings of 140/90 mmHg or higher.
These definitions were updated in 2017 partly based on findings from the SPRINT trial published in 2015. The study tested more intensive blood pressure treatment targets compared to standard guidelines.
The SPRINT Trial Showed Benefits of Lower Blood Pressure
The SPRINT study randomly assigned high cardiovascular risk participants without diabetes to either standard treatment with a systolic blood pressure target under 140 mmHg or more intensive treatment aiming for under 120 mmHg.
After a median 3 years of follow-up, the group with lower blood pressure had significantly fewer cardiovascular events, with a 25% relative risk reduction. They also had a 27% reduction in all-cause mortality.
This led to the current guidelines recommending more aggressive hypertension treatment for many patients compared to prior decades.
Home Monitoring Reveals True Average Blood Pressure
The SPRINT trial used careful at-home monitoring to accurately assess participant blood pressure over time. Single office readings can often misrepresent a person’s typical pressure.
Home monitoring, using good technique with an automated or manual cuff over multiple occasions, gives a better picture of average blood pressure outside the clinic setting.
Small Pressure Differences Compound Cardiovascular Risk Over Years
Like smoking and high cholesterol, chronic elevated blood pressure causes compounding damage to arteries and the heart muscle over time. Even small pressure differences well within the “normal” range likely drive increased cardiovascular and cognitive decline risk over decades.
Aggressive management of blood pressure, informed by home monitoring averages, provides an opportunity to significantly reduce lifetime cardiovascular event risks.
Who Should Have Their Blood Pressure Evaluated?
Blood pressure screening is recommended at least annually for healthy adults over 18 years old. Those with hypertension or at higher risk for cardiovascular disease often require more frequent follow-up measurements.
Even teenagers should have occasional blood pressure checks during routine well visits to establish baseline norms.
When is Treatment Indicated for High Blood Pressure?
Lifestyle changes are first-line recommendations for newly discovered cases of elevated blood pressure. This can include dietary improvements, weight loss, exercise, and stress reduction.
If blood pressure remains 120-129/under 80 mmHg after 3-6 months of lifestyle changes, medications may be appropriate based on overall cardiovascular risk profile and other medical history.
Individuals meeting criteria for stage 1 or 2 hypertension typically merit medication initiation along with lifestyle optimization.
What Medications Effectively Lower Blood Pressure?
Many safe and effective oral medications exist to lower blood pressure. Common drug classes include:
- ACE inhibitors
- Angiotensin receptor blockers (ARBs)
- Calcium channel blockers
- Beta blockers
- Diuretics
Treatment regimens often combine drugs from complementary mechanisms of action. Home monitoring helps inform optimal medication dosing.
Take Charge of Your Heart Health Through Blood Pressure Awareness
Along with cholesterol levels and smoking, blood pressure serves as a vital barometer of cardiovascular wellness. Monitoring yours through at-home measurements empowers lifestyle and medication adjustments to mitigate hypertension risks.
Small, sustained reductions in blood pressure compound over years to drive meaningful gains in heart attack and stroke prevention, adding both quantity and quality of life.
