The guidelines change the definition of high blood pressure – also called hypertension – to begin when measurements show a top number of 130 or a bottom number of 80. That changes from 140/90, where it had been since 1993.
With this change, it is estimated that 59% of all African-American men will be classified as having high blood pressure, up from 42%. Fifty-six percent of African-American women – who had the highest rate previously at 46% – now have high blood pressure. Forty-seven percent of White men and 41% of White women have high blood pressure.
As startling as the change might seem, however, local doctors say it’s really a recognition of what medical professionals have known for some time: that the risk of heart attack and other cardiovascular impacts begins even before a person reaches the high blood pressure mark.
Dr. Joseph Thibodeau, a cardiologist with CHI Health Clinic, said the new guidelines mean nearly half the adult population will be categorized as hypertensive, which fits with the fact that two-thirds of adult Americans are overweight or obese.
“So it’s as much the recommendations catching up with the shape of America,” he said.
“Earlier intervention is important for African-Americans,” said Kenneth A. Jamerson, M.D., a guideline author, cardiologist and professor of cardiovascular medicine with the University of Michigan Health System. “Hypertension occurs at a younger age for African-Americans than for Whites. By the time the 140 over 90 is achieved, their prolonged exposure to elevated blood pressure has a potential for worse outcome.”
Heart disease also develops earlier in African-Americans and high blood pressure plays a role in more than 50 percent of all deaths from it. African-Americans have a higher rate of heart attacks, sudden cardiac arrest, heart failure and strokes than White people. In addition, their risk is 4.2 times greater for end-stage renal disease, which often progresses to the need for dialysis multiple times a week and ultimately to kidney transplantation or death.
“Hypertension has been a blight on the African-American community for many, many years. It’s time for us to get over it,” said Kim Allan Williams, Sr., chief of cardiology at Rush University Medical Center in Chicago. “People need to get screened and get care.”
Those newly added to the ranks of people with high blood pressure, or hypertension, won’t necessarily start medication right away, however.
Instead, a doctor’s first focus will be on lifestyle, encouraging patients to cut salt, eat a more heart-healthy diet, and get adequate exercise. In addition patients should quit smoking and drink no alcohol or moderate amounts. In fact, the number of new patients who will require high blood pressure medication is expected to increase only 2%.
“We’re not just going to throw medicines around as much as we want to get heart-smart behavior and diet,” said Dr. Thomas Brandt, a cardiologist with Methodist Physicians Clinic.
The decision regarding if and when a patient should move on to medication, however, is an individual one and one that’s a little more nuanced than a first glance at the guidelines might suggest.
Heart attack risk technically starts to increase at 115/75, Thibodeau said. Above that, doctors have to start looking at where to draw the line and start treatment.
Among other things, they consider a patient’s risk of heart disease or stroke using a calculator that includes factors such as blood pressure readings, existing blood pressure medication, cholesterol levels, smoking, diabetes status and age.
Guidelines for patients considered at high risk of a cardiac event changed back in April, he said, so doctors already have been pushing those patients to 130/80 for the past six months with medication.
For those at low risk — less than a 10% chance of a cardiac event over the next 10 years — doctors will continue to recommend lifestyle changes until they reach 140/90. The key for patients, Brandt said, is to know their numbers, a step the American Heart Association has been recommending for years.
“If you don’t know your numbers, you don’t know you’re at risk,” he said.
“You may not have to take a pill,” said Jamerson. “These discussions are more work for a provider, but it’s great for the patient. They’re brought into the process.”
If medicine is needed, the new directions are to treat earlier and more aggressively to get blood pressure into the normal range right off the bat.
“Our data shows controlling early works,” Jamerson said.
Jamerson said there is no downside to more aggressively treating high blood pressure from the start.
“If one takes the long view, then everyone should appreciate this approach,” he said. “The cost of medications to treat more people is small, when compared to the cost of a stroke, cardiovascular disease or heart failure. It’s a no-brainer.”
The guidelines are also offering race-specific treatment recommendations by addressing drug efficacy in African-Americans. The guidelines point out that thiazide-type diuretics and/or calcium channel blockers are more effective in lowering blood pressure in African-Americans when given alone or at the beginning of multidrug regimens.