SAN FRANCISCO—It’s been more than three years since the release of the Sixth Report of the Joint National Committee on the Prevention, Detection, Evaluation, and Treatment of High Blood Pressure, but already there has been a shift in thinking about what constitutes high blood pressure. According to experts at the 16th Annual Scientific Meeting of the American Society of Hypertension, a blood pressure reading of 140/90 mm Hg, which previously separated hypertension from nonhypertension, may not be adequate for all patients.

Matthew Weir, MD, of Johns Hopkins University, who chaired a symposium on the subject, said that “there’s been a major paradigm shift. It’s not the diastolic of 90 and it’s not the systolic of 140. The real issue is what’s the right blood pressure for preventing cardiovascular disease and renal risk in a given patient.”

According to Joel Neutel, MD, of the Orange County Heart Institute in Orange, California, the new clinical agenda is to prevent and treat hypertension as early in life as possible and to aggressively treat high blood pressure at the other end of life—in people in their 70s and 80s.

EVEN SMALL REDUCTIONS COUNT

Also challenging the previous gold standard of 140/90 mm Hg, Dr. Neutel pointed out, “You can now see that it’s very early on, at a systolic of about 120, where cardiovascular disease starts increasing in the Framingham [Heart] Study. The incidence of cardiovascular disease starts to become very steep somewhere between 120 and 130 mm Hg.” He added that lowering the systolic pressure this much may be harder to achieve in older patients. But he noted that numerous epidemiologic studies have shown that older patients will benefit even with small reductions in blood pressure, although they may not get below 140 mm Hg.

According to Dr. Neutel the Systolic Hypertension in the Elderly Program (SHEP) showed definitively that even small reductions, although not to the goal of less than 140 mm Hg systolic, can drastically reduce heart attacks and strokes in the elderly. SHEP also contradicted the old idea that it was okay to have systolic pressure that was “a hundred plus your age.” Lowering diastolic pressure is usually more attainable in older patients, he noted. Achieving the best results for both components of the blood pressure, he added, will probably require multiple drugs. “You’ll do far better with two drugs, and many will need three or four.”

NOT JUST HEART ATTACKS

The benefit of lowering blood pressure from the classic 140/90 mm Hg to something more like 130/85 mm Hg also applies to renal function, commented Franz Messerli, MD, of the Ochsner Clinic in New Orleans. Reducing blood pressure to the lower numbers means “many more years before you run out of renal function, as well as providing dramatic drops in neuropathy and other problems, even with reductions as small as 3 mm Hg,” he said. The benefit of small drops in blood pressure in preventing strokes and other cardiovascular events had been shown, “even before the era of modern drugs,” he added.

HYPERTENSION KNOWS NO AGE

Jonathan Sorof, MD, Codirector of the Houston Pediatric and Adolescent Hypertension Program at the University of Texas–Houston Medical School, reported that hypertension was rising among young people. Three sequential screenings of 2,460 predominantly ethnic minority middle and high school students showed an estimated final overall hypertension prevalence of 9.5%. “We found body mass index [BMI] was a major independent factor in elevated systolic blood pressure even in students whose BMI was in the normal range,” he said. Such overweight and obese children “could very well be in danger of developing cardiovascular disease later in life.”

MODIFYING BLOOD PRESSURE

According to Marvin Moser, MD, the length of time a hypertensive patient should adhere to behavior modifications alone, such as salt restriction, weight loss, and an exercise program, depends on the individual’s risk profile. “If you’re a 45-year-old woman with blood pressure of 150/90 mm Hg with no other risk factors, a nonsmoker, and no evidence of left ventricular hypertrophy or microalbuminuria, you might stay on lifestyle modifications for six months or longer,” he said. “On the other hand, a 45-year-old man with diabetes and a blood pressure of 150/90 mm Hg would need both lifestyle modifications and drug therapy.” This therapy would probably involve diuretics, ß-blockers, or ACE inhibitors as initial treatment, he said, although many patients will need to be on drug combinations. All the newer agents, in his view, need to be compared to the gold standard, which are the diuretics. Dr. Moser is a Clinical Professor of Internal Medicine at Yale University.

Dr. Moser also commented that “we should be spending more time with diabetics on their blood pressure control,” rather than just thinking about glycemic control, in order to reduce their cardiovascular risks. Another often-neglected group, he said, is the elderly. “Let’s not kid ourselves—the elderly will benefit from lowering of blood pressure even though we may not be able to lower systolic to 140 mm Hg or below. The diastolic can be controlled at the rate of 85% to 90% in this age group,” he said, while only about 60% of them will have adequately controlled systolic pressure.

“Why aren’t we doing a better job,” he asked, “when we know the benefits and have available therapy? I think we have to sit back and stop arguing about whether drug A is better than drug B. Most of them are effective in reducing blood pressure, although I think all combination therapies should include diuretics. Diuretics should be used as either an initial therapy or in a combination.” Lifetime sodium restriction and, of course, stopping smoking will also help, he said.

AN APPROPRIATE MEASURE

Regarding proper blood pressure evaluation, Joseph Schwartz, PhD, of the State University of New York at Stony Brook, said that 24-hour ambulatory systolic measurements are a stronger predictor of adverse cardiac events than is the measurement of diastolic blood pressure alone or the full blood pressure reading taken in the physician’s office. He and his colleagues looked at two large studies—the PIUMA study in Italy, which tracked 2,620 persons between ages 18 and 94 for an average of 4.8 years, and the Cornell study in New York City, which followed 1,296 patients for an average of 10.3 years. The researchers found that the incidence of stroke, myocardial infarction, cardiovascular death, and all-cause mortality was better predicted with the 24-hour ambulatory pressure monitoring, although physician blood pressure monitoring had “some predictive power.”

NR