High blood pressure still sneaking past doctors, Stanford study shows

May 1 2008

Despite the well-known dangers of high blood pressure, major shortfalls still exist in the screening, treatment and control of the disease even when patients are getting a doctor's care, according to a study from the Stanford University School of Medicine.

In a unique look at how blood pressure, or hypertension, is being addressed once a patient steps into a doctor's office, the study reported a lack of routine blood pressure screening and a low percentage of patients who are achieving recommended blood pressure goals after diagnosis.

"Doctors should be screening more routinely during all office visits," said co-author Randall Stafford, MD, PhD, associate professor of medicine at the Stanford Prevention Research Center. "Dual medication treatment should be seen as standard therapy and intensive lifestyle changes should be encouraged."

Often referred to as "the silent killer," high blood pressure affects more than 65 million people in the United States and is one of the most important and preventable risk factors for cardiovascular disease, strokes and kidney disease. High blood pressure can quietly damage your body for years before actual symptoms develop.

It's this lack of symptoms that is one of the major reasons for gaps in care, researchers said.

"This is a problem that spans much of preventive medicine," Stafford said. "The treatment itself doesn't make patients feel better. If somebody has asthma, they know that if they stop taking medication they're going to start wheezing. With blood pressure medicines, patients don't feel any different."

Because of this, many patients themselves don't follow the doctor's orders or return for follow-up care.

"We know many patients don't take the medications they were prescribed for the doses that were prescribed nor for the duration that was prescribed," said lead author Jun Ma, MD, PhD, a former research associate at Stanford Prevention Research Center who now works as associate staff scientist at the Palo Alto Medical Foundation Research Institute.

The study, published in the May issue of the journal Hypertension, analyzed data from the National Ambulatory Medical Care Survey 2003-04, a federal survey that captures the provision and use of medical care services in private physician offices in the United States.

"It's the first study that we know of that specifically looks at nationally representative rates of Americans who are screened, treated and controlled for hypertension in the primary care setting," Ma said. The survey recorded such details as whether the blood pressure cuff was brought out, whether appropriate types of medication were prescribed and whether treatment achieved its goal.

"There's been an assumption in the past that these problems have been solved," Stafford said. "Unfortunately, our study indicates a continuing problem. Only 39 percent of patients who are treated were at the recommended blood pressure levels."

The first step toward improving treatment is to increase routine blood pressure screenings even in specialists' offices, Stafford said.

Blood pressure was measured in only 56 percent of all patient visits, according to the survey. That rises to 93 percent in visits by patients diagnosed with hypertension.

"Many physicians in specialized practice appear to feel they don't need to measure blood pressure," he said. The thinking goes, "'I'm a dermatologist so I don't need to screen for high blood pressure.' But because there's a high likelihood of high blood pressure getting missed, we need to take advantage of all opportunities for screening."

The study also found disturbingly high blood pressure levels for certain populations that are most in need of controlling the disorder. Only 20 percent of hypertensive patients who also have diabetes or kidney disease had their blood pressure controlled.

"We need to target lower blood pressure levels in individuals with kidney and heart disease," he said. "The one-size-fits-all, 140/90 mm Hg goal isn't adequate for people who are at higher risk. Their blood pressure should be below 130/80 mm Hg, if possible."

Once a patient is diagnosed with hypertension, physicians need to make clear to patients the types of treatment that will be necessary. And they need to strongly encourage lifestyle changes.

"Physicians may need to tell patients that it's likely to take two or more medications to get blood pressure under control," Stafford said. "They also need to use a comprehensive strategy to attack high blood pressure that includes recommended changes in lifestyle: weight loss, reduction in sodium, a plant-based diet, increases in physical activity. Both patients and physicians need to take advantage of all available strategies."

The study was funded by the National Institute on Aging, the U.S. Agency for Healthcare Research and Quality and the National Heart, Lung, and Blood Institute.