High blood pressure is one of the most prevalent health problems in the United States, and it now affects nearly half of adults in the country, thanks to sweeping changes to what constitutes hypertension announced by the American Heart Association last month. The revisions also say that younger adults and the elderly are now considered to be at higher risk of heart disease, stroke and other chronic illnesses.
The American Heart Association (AHA) released new guidelines in November that lowers the bar for what constitutes high blood pressure, meaning patients who were previously told their blood pressure was under control or only amounted to pre-hypertension are now considered at risk. High blood pressure is one of the leading causes of preventable heart disease and stroke deaths, and damage to blood vessels can start even at lower end of high blood pressure, according to the AHA.
Blood pressure measurements are based on systolic and diastolic readings that reflect pressure in blood vessels during the heartbeat and when the heart is at rest. Previously, anyone with a diastolic reading of 140 and a systolic reading of 90 was considered to have high blood pressure, but the guidelines bumped the numbers down to 130/80. It may not sound like much, but the AHA predicts that the number of adults with high blood pressure will shoot from 32 percent to 46 percent under the new metric.
Patients with a systolic blood pressure between 130 and 139 double their risk of cardiovascular complications, said Paul K. Whelton, lead author of the guideline changes, in a Nov. 13 statement.
"We want to be straight with people -- if you already have a doubling of risk, you need to know about it. It doesn't mean you need medication, but it's a yellow light that you need to be lowering your blood pressure, mainly with non-drug approaches."
The medical community has been expecting the changes for a few years now, said Dr. Geoffrey Yoon, a cardiologist and the heart failure medical director at El Camino Hospital. A major clinical trial involving more than 9,300 participants known as the Systolic Blood Pressure Intervention Trial (SPRINT) found that patients who received treatment that brought their systolic pressure down to 120 were less likely to suffer a heart attack or a stroke. The new standards will most significantly affect men and women under the age of 45, as well as patients over the age of 65 years old who were previously considered less at risk.
We've been anticipating this," Yoon said. "More and more data has come out that treating blood pressure earlier and more aggressively will lead to better outcomes."
Bay Area residents are less likely to suffer from hypertension compared to the rest of the country, but the rates are still high. More than a quarter of Santa Clara County residents, 27 percent, have been diagnosed with high blood pressure, according to El Camino Hospitals' Community Health Needs Assessment last year. Black people, men and older adults are more likely to be diagnosed with high blood pressure compared to county residents overall.
Data from the U.S. Center for Disease Control put the county's hypertension death rate at 249.2 per 100,000 residents between 2013 and 2015, which is higher than other Bay Area counties including Alameda (230.7), Contra Costa (225.3), San Francisco (172.3) and San Mateo (164.2) counties.
No cause for alarm
Many of the people with the narrow systolic reading between 130 and 140 who are now considered hypertensive likely won't have to rely on drug treatment to bring down their blood pressure, Yoon said. Losing weight, getting more exercise and adopting a healthier diet can go a long way and can even be more effective than medication. Patients are often advised to follow the Dietary Approach to Stop Hypertension (DASH) diet, which includes fruits and vegetables, lean meats and less salt.
The new guidelines may have been a long time coming, but they weren't developed without some controversy over how to interpret the data. The results from the SPRINT trial make a strong argument that anyone above 120 systolic blood pressure should seek treatment, but some experts argued that the measurement techniques used in the study consistently resulted in lower readings than what patients typically see in a doctors office, meaning a standard of 120 would be an overshot. What's more, intensive drug treatment for high blood pressure isn't without its own problems, and could put more patients at risk of kidney disease.
"I think anytime there are changes in blood pressure guidelines it's controversial, because there's a big patient population who (is) older and (has) a lot of side effects from blood pressure medicine," Yoon said.
Because hypertension often has no symptoms, frequent blood pressure readings both at the doctor's and at home are the best way to catch the problem early on. The El Camino Healthcare District launched a public awareness campaign with the American Heart Association Silicon Valley in 2015 to bring blood pressure screening events and free hypertension management classes to residents in Mountain View and neighboring cities. The district committed $71,000 to the hypertension initiative this year, which will go towards paying for hypertension clinics and "Heart Health Hubs" at places like grocery stores and shopping centers.
Board member Dr. Peter Fung, who spearheaded the partnership, told the Voice in an email that the AHA guidelines -- and the 1,000 studies that led up to the announcement last month -- doubles down on the importance of addressing hypertension early on, and should put to rest the myriad of excuses patients use to justify ignoring elevated blood pressure results.
"It should erase all doubts that something needs to be done if the blood pressure is above 120 systolic, as this is the level that the nasty effects of hypertension start to set in, and that by 130, the risk is already double," Fung said.
Patients shouldn't be overly cautious about using blood pressure medication if lifestyle changes aren't enough to bring blood pressure down to 120, Fung said. The side effects of the drugs are minimal, and are "quite safe" as long as patients regularly check in with their doctors.
Other guideline changes stress the importance of using proper technique for measuring blood pressure, and to base blood pressure on an average of two to three readings taken on at least two different occasions. Home blood pressure readings are particularly important because some patients have so-called white-coat hypertension, where the stress of bring in a doctor's office raises blood pressure temporarily.
The guidelines also warn of "masked" hypertension where the opposite is true, and blood pressure readings are actually lower in a medical setting than at home. Those patients are at risk and may not know it, Yoon said.
The AHA update also reversed course on blood pressure standards for the elderly, which used to be more lenient than for younger patients. The SPRINT trial found older patients "greatly" benefited from blood pressure control, Yoon said, and that people over the age of 65 with elevated blood pressure are actually at greater risk.
More information on the AHA's blood pressure monitoring programs can be found at ccctracker.com.