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Friday, Dec. 17, 2004
Blowing A Gasket
By Jeffrey Kluger; Missy Adams
Michael Robinson, 35, is young enough to remember his glory days playing college basketball, which was one reason he was so
surprised when just walking to his car started to wear him out. Robinson's weight certainly didn't help: 345 lbs. is a load to carry,
even on a 6-ft. 9-in. frame. His family history worked against him too. Both his parents have high blood pressure, and his father
and brother are diabetic. And he didn't do himself any favors by allowing seven years to elapse since his last checkup. When his
persistent fatigue finally drove him to a doctor, he learned the wages of so much neglect. His blood pressure was topping out at a
monitor-popping 166/120, and he was in the early stages of heart failure.
A year later, the Ashburn, Va., man exercises regularly, takes hypertension medication, and has dropped his fast-food burger habit
in favor of low-fat grilled chicken. He has a lower-stress job with the county department of family services and is the father of a
new baby boy. "I'd like to be around for him," he says. His new blood pressure should help. It's 120/80.
Robinson's turnaround was impressive, but according to the experts, such stories are increasingly rare. At least 65 million
Americans--a third of all adults over 18--are thought to suffer from hypertension (the technical term for persistent
high blood pressure), up from 50 million just 10 years ago. Worse, doctors last year defined a new category of risk,
prehypertension, in a borderline pressure range that is now considered a bright red flag of trouble to come. Moreover, when
people do address their blood-pressure issues, they don't always do it very well. Only about a third of all patients in treatment for
high blood pressure have their numbers under control. Over the course of our lives, perhaps 90% us will develop a blood-pressure
problem, and at least half of us will die from either heart disease or stroke--hypertension's frequent endgames.
Alarmingly, it's not just middle-agers and seniors who are turning up with the problem. So are kids. Dr. Keith Ferdinand treats
patients in a community health clinic in one of the poorest neighborhoods in New Orleans and has lately been shocked to see more
and more young patients coming in with elevated pressure. Four years ago, he treated his first 18-year-old heart-attack victim.
"We're seeing not only a growing number of cases of hypertension in young people," he says. "We're also seeing a growing number
of complications from it."
The blood-pressure problem was never supposed to get this far. Not all that long ago, the battle against hypertension was touted as
one of the U.S.'s great public-health success stories. Almost absurdly easy to detect--a few painless seconds with a pressure cuff
does it--hypertension is comparatively simple to treat with weight loss, lifestyle changes and a little medication. In the 1970s,
doctors began tackling the condition aggressively, and as the percentage of people being treated crept up, the incidence of
hypertension-related conditions fell. Strokes alone declined more than 50% from 1972 to 1994. Clearly, the country was closing in
on a big medical win--with medications like beta blockers and angiotensin-converting enzyme (ACE) inhibitors making big
contributions to that success. But the ball has been dropped, and the reasons, in retrospect, are clear.
In the cause-and-effect universe of epidemiology, societies get the blood pressure they deserve, and we Americans have earned
ourselves some huge problems. We are heavier than we have ever been, with 65% either overweight or obeseincluding 15% of kids.
We're lazy too. Only 24% of us exercise vigorously at least three times a week. We smoke too much (22% of adults still light up),
drink too much, and with our fetish for fast and processed foods, we're practically pickling ourselves with salt.
Worse, demographics ensure that the hypertensive population is only going to grow. As the bow wave of the baby-boom generation
prepares to hit 60, more than 77 million of us will begin entering our golden--and most pressure-prone--years. Following the
boomers will be their kids and grandkids, with up to 3% of the juvenile population thought to be hypertensive. "More than 25% of
children with high blood pressure may already have some cardiac thickening," says Dr. Bonita Falkner, a professor of medicine
and pediatrics at Thomas Jefferson University in Philadelphia.
In the face of those grim numbers, the medical and pharmacological communities are scrambling. Drug companies are rolling out
new medications to join the arsenal of blood-pressure drugs already on the shelves. Physicians are routinely checking pressure in
younger and younger patients. Public-health officials are launching new information campaigns, trying to raise public awareness
in the hope of getting to the at-risk population before it's too late. Such large-scale mobilization may be the only way to get the
problem back in check. "There's good evidence hypertension can be controlled," says Dr. Darwin Labarthe, acting chief of
cardiovascular health at the Centers for Disease Control and Prevention (CDC), "but it will take an intense, sustained effort."
BREAKING DOWN
One reason hypertension can be such a stubborn problem is that it involves so many of the body's interlocking systems, and lying
at the center of it all is the heart. The heart doesn't so much pour blood through the circulatory system as punch it through, forcing
six quarts of heavy liquid beyond the torso and out to remote provinces like the feet, hands and head. Unfortunately, the riptides of
the circulatory system are not always kind to the vessels that have to carry the load. Every time the heart contracts, blood not only
rushes ahead through the vessels but also presses against the walls. That pulse is the systolic pressure, the first number in your
blood-pressure reading. When the heart relaxes between beats, the pressure eases too but only to a point. That is the diastolic
pressure, the second number. The force of both pressures is measured by how high a pulsing artery can push a column of mercury
in a blood-pressure monitor. In general, 120 mm during a beat and 80 mm between beats are considered normal.
But there are a lot of things that can throw off the calibration of the whole fragile system, starting with the vessel walls. When
we're young, our vessels are healthy and springy, easily stretching and contracting to accommodate blood pressure as it rises and
falls. The arteries, which are a type of muscle, even pulse to help keep blood moving along. But the fibers that make up the
scaffolding of the vessel walls can take only so much flexing. As we age, the rubbery tissue slowly gets replaced with stiffer
collagen. The vessels don't expand as well anymore, but the blood keeps rushing through at the same rate, increasing the pressure.
The higher the pressure climbs, the more punishment the walls take, and the more collagen is added. "The vessel wall becomes
almost like concrete," says Dr. Michael Weber, a past president of the American Society of Hypertension.
The kidneys too play a big role. The urinary and renal systems govern not only the quantity of water that is kept or dumped by the
body but also its composition. Drain or retain too much sugar, potassium or countless other essential components, and the
chemistry of the whole body goes awry. One of the things the kidneys keep an especially close watch on is salt. The more sodium
you hold, the more water your body retains, storing it first in the bloodstream and then off-loading it into tissues. When your
system gets waterlogged, overfilled vessels feel the strain.
The kidneys work hard to keep that from happening. If salt content is too high, the body's water content will be elevated too. The
system responds by slowing down the manufacture of renin, an enzyme that increases water retention. Dialing back the renin also
dials back the production of angiotensin, a protein that constricts blood vessels. Should the salt level fall too far, the body reverses
the procedure, cranking up renin to hold on to water and releasing angiotensin to tighten vessels. There are a lot of things that can
throw that system off, including kidney disease and tumors on the thyroid gland. In most cases, however, it's simply too little
exercise, too much food and too much salt.
"The great majority of people with high blood pressure have what is called essential hypertension," says Labarthe. "That is high
blood pressure that is a reflection of lifestyle."
Whatever the causes of hypertension, doctors have been pretty clear about what its yard markers are. A reading of 120/80 or
below is considered normal; 140/90 marks the onset of hypertension; 160/100 is Stage 2 hypertension; 220/120 is the onset of
what is known as malignant hypertension, pressure so high that fluid is squeezed from vessels into the brain and blood leaks out of
capillaries into the liquid that fills the eyeballs. "Malignant hypertension is a medical emergency," says cardiologist Richard
Devereux of Cornell University Medical College.
THE DAMAGE DONE
The sinister thing about hypertension is that most of the creeping harm it does happens without the patient's knowing it. People
with malignant hypertension may experience such symptoms as headaches or coldness in the hands and feet, but they also may
not. People with less severe hypertension may experience nothing at all until calamity strikes. One of the commonest of those
pressure-related disasters is heart attack. The higher pressure climbs, the harder the heart has to pump to push the blood. Like any
other muscle called on to do more work, the heart responds by enlarging, chiefly in the left ventricle, which is its main pumping
chamber. Increased muscle mass is fine in the biceps, but it's bad in the heart, which must be lean and flexible to work as it should.
Worse, if a person with hypertension has high cholesterol, the deteriorating condition of vessel walls creates rough spots that serve
as toeholds for circulating fats. As fat collects into plaques, they can break free, particularly if vessels are repeatedly being
slammed by blood rushing out from the overworked heart. Breakaway plaque can lead quickly to a heart attack.
The brain can take a bad hit too in the form of stroke. About 75% of strokes are caused by a blood clot or loose plaque racing
through the system and lodging in the vessels of the brain, where it cuts off the flow of oxygenated blood. Other strokes are
essentially hemorrhages, ruptures in brain vessels that give way under elevated pressure.
Scientists studying Alzheimer's disease have also uncovered a possible link to uncontrolled blood pressure. When they scrutinized
the brain vessels of people who had died of Alzheimer's, they found that those with a history of hypertension during middle age
had tiny changes that did not appear in healthy individuals. "The question is, Where do the micro changes come from-longstanding hypertension or high cholesterol?" says Dr. Richard Mayeux, co-director of Columbia University's Alzheimer's
research center, who is studying the connection. If either of them turns out to be involved, controlling both may be an unexpected
way to reduce dementia risk.
With that surprising exception, the basic health issues associated with hypertension have not changed. What's new is how deep the
pool of at-risk people has become and how serious the danger for them is. The National Heart, Lung and Blood Institute (NHLBI)
estimates that of 65 million hypertensive Americans, nearly 20 million are not aware they have the condition. Worse, the 65
million figure is just an estimate of the vulnerable population, and that population is a constantly moving target. Every time the
nation's obesity needle ticks upward, the number of hypertensive Americans does too.
What's more, the closer experts look at how doctors actually diagnose high blood pressure, the more they think they've been
grading on a too generous curve. Traditionally, readings between 120/80 and 140/90 have been labeled borderline, less likely to
require drugs or other intervention. Now the NHLBI believes that patients may begin approaching danger when their systolic
reading--the first number--is as low as 115. Although pressure varies from moment to moment and day to day, a reading that hits
the danger zone on two separate visits to the doctor may signal trouble.
"There is a doubling of cardiovascular risks that begins at this point," says Dr. George Bakris of Rush University Medical Center in
Chicago. That means up to 45 million people who thought they were on safe ground may be at risk.
To try to make this point as emphatically as possible, the NHLBI labels the borderline pressure range "prehypertension," a mildly
alarming term that was chosen for precisely that reason. "We convened focus groups; presented them terms such as high normal,
borderline and abnormal vascular response; and asked them which would get across the idea that they had to take action," says
Bakris. "Ninety-eight percent said prehypertension would do it."
CULTURE CLUB
If the nation's hypertension problem is going to be controlled, epidemiologists know that one place they're going to have to start is
in the Latino and black communities. Mexican Americans have a hypertension incidence 5.5% higher than that of whites, and
African Americans a whopping 43% higher. Epidemiologists have advanced any number of explanations for the hypertension
problem in the black population. One of the most intriguing--if least provable--has been that the brutal conditions aboard slave
ships crossing the Atlantic served as a sort of adaptive choke point, selecting for people with a tendency to retain salt and water.
This allowed them to survive the murderous journey without succumbing to thirst but predisposed their descendants to
hypertension. Dr. Lawrence Appel of the Johns Hopkins University School of Med-icine believes that modern-day African
Americans do process sodium a bit differently from whites and may even have a less reactive renin-angiotensin system.
But while many researchers concede that genes may play such a role, they believe cultural variables are far more important.
"African Americans generally have lower economic well-being and the ability to make lifestyle changes and purchase medicines,"
says the CDC's Labarthe. Indeed, a 10-country, 85,000-person study revealed that, worldwide, it is whites who are as much as
twice as likely to suffer from hypertension, with countries like Poland and Finland--where diets are high in fat and low in fruits
and vegetables--leading the way. In a socioeconomic environment in which African Americans are often forced to eat cheap,
unhealthy food (the National Institutes of Health is worried particularly about cured meats, pickled foods, canned fish, salty
snacks and sauces), it's no wonder their blood pressure is high.
Pregnant women are another high-risk group, whether they had hypertension going into the pregnancy or not. High pressure
during pregnancy--160/110 or above--can lead to maternal seizures and even death. It can also cause premature births or
stillbirths.
The newest and most surprising at-risk population, however, is the kids, a group in which hypertension, until recently, could not
even be uniformly diagnosed. Optimum blood pressure changes with age and body size, and what's right for an adult is wrong for a
preteen, to say nothing of a baby. A 2-year-old girl in the 50th percentile for height may have an average blood pressure of just
88/45. That same girl at age 10 should be up to 102/60, still far below the traditional adult benchmark of 120/80. The NHLBI now
recommends making blood-pressure readings a part of all visits to the pediatrician. Any child who repeatedly scores in the 95th
percentile or above for height, age and sex should be considered in danger.
FIXING WHAT'S BROKEN
What to do when any patient--child or adult--has hypertension varies from case to case, but some steps are obvious. Smoking,
which is potentially lethal for everyone, is poison for the hypertensive. Tobacco accelerates heart rate and constricts blood vessels,
just what you want to do if you're trying to make a hypertension problem worse but a lousy idea if you want to get well.
Controlling weight is also vital. The body tunes and retunes a lot of dials to keep its blood pressure balanced, and obesity twists
those knobs in all the wrong ways. For one thing, increased body mass means higher blood volume, straining the circulatory
system. Carrying extra weight also causes the heart to overwork--no favor to a left ventricle that may already be enlarged.
Additionally, people who are overweight generally don't get that way eating fruits, vegetables and lean meats; their diet tends to be
high in salt, fats and processed foods, just the things hypertension feasts on.
Another variable is not just how much weight you're carrying but where you're carrying it. Most of our swaddling of fat is located
under the skin and over the muscle, but around the abdomen there is another layer beneath the muscles. This so-called visceral fat
produces inflammatory molecules that lead to insulin resistance and diabetes. The same molecules also destroy nitric oxide, which
is critical to the ability of the blood vessels to relax. "Central fat is a linchpin in the abnormalities that lead to hypertension," says
Dr. James Sowers of the Downstate Medical Center in New York City.
If an overweight or otherwise out-of-shape person is lucky enough to have mere prehypertension, the condition can often be
controlled with diet and exercise. "If someone comes to me with prehypertension," says Bakris, "I pull out my pad and write a
lifestyle prescription first."
It's a prescription that can work. The NHLBI promotes an eating plan called the DASH diet (for dietary approaches to stopping
hypertension), with menus low in fats, salt, cholesterol, red meat and sweets and high in fruits, vegetables, grains, fish, poultry,
nuts and low-fat dairy foods. Alcohol consumption should be limited, with men having two drinks or fewer a day and women--or
men with small body mass--just one. In the very short term, alcohol may lower blood pressure; over time, however, it elevates it.
Exercise is important, with aerobic activity--as little as 30 minutes of brisk walking--recommended for three or four days a week.
Even though pressure briefly rises when you exercise, the workouts cause the heart and other muscles to become more efficient
and require less oxygen. This reduces cardiovascular demands and lowers overall pressure.
STRONG MEDICINE
For many people, lifestyle changes aren't enough. In such cases, drugs are the answer. There are five classes of blood-pressure
medication, each of which works on a different link in the hypertension chain. Diuretics, which cause the body to excrete water
and lower the load in the vessels, are the workhorse drugs with the longest history and the most direct effect. Diuretics work best
in older patients, since younger metabolisms sense the change in fluid volume and react by activating the renin-angiotensin
system to constrict vessels and boost pressure, negating the effects of the drugs.
The other categories of medications include beta-blockers, which moderate heart rate and the angiotensin system; calciumchannel blockers, which obstruct the tiny ducts in cells through which calcium ions must pass to constrict blood vessels; ACE
inhibitors, which reduce the production of angiotensin and thus reduce constriction; and angiotensin-receptor blockers, which
allow the protein to be produced but prevent some of it from being taken up by the cells. All four of these have the same goal--to
unclench the tensed circulatory system--and they are often prescribed in combination.
If the drugs are going to work, patients must actually take them, and doctors find it maddeningly hard to ensure that they do.
Many of the medications can have mild side effects, including fatigue, dry cough, and occasional erectile difficulties in men--not
surprising, since you're manipulating the body's circulatory hydraulics. When people face a disease that causes no symptoms and a
treatment that does, it's no surprise which one they sometimes choose. "You prescribe medication," says Weber, "and within a
year, 50% of people quit taking it."
That's an exceedingly bad idea, not only because the alternative to medication may be early death but also because side effects can
be easily minimized or eliminated, particularly with so many drug combinations to try. And while most people need to continue
taking hypertension medications for life, that doesn't mean the dose can't be lowered. Says Rush University's Bakris: "I tell
patients that if they reduce their grocery bill they can also reduce their medication bill."
Women suffering from pregnancy hypertension may be advised not to take some or all of the five classes of drugs, although the
doctor must weigh the risks of the medication against the risks of hypertension. In moderate cases, proper diet and exercise may
be the best prescription until after the birth, when blood pressure will settle back to whatever its natural level will be and the need
for drugs can be looked at again.
For all people, relaxation techniques such as yoga and meditation may help. Stress contributes to hypertension, in part by causing
the release of cortisol and adrenaline, which in turn boost blood pressure. In one recent study at Yale University, volunteers in a
small sample group showed measurable relaxation of arteries after sessions of yoga and meditation, although the improvement
was not enough to eliminate elevated pressure. Doctors treating hypertension or prehypertension thus do not recommend
relaxation as a substitute for diet, exercise and medication. As an adjunct, however--one more way to unknot the body--it may
help.
No matter what form hypertension treatment takes, patients have to accept that like diabetes, the disease is one that will never
really go away. As pressure comes down, however, the body should begin to heal. Hardened arteries may never regain all their lost
limberness, but they do improve. Enlarged hearts change even more dramatically. Cornell's Devereux cites a study in which the
portion of the heart that was made up of healthy tissue went from 30% to 75% in patients on medication to control their pressure.
Treating elevated cholesterol can help too, clearing fats from the recovering circulatory system.
Manage those kinds of improvements, and even the most severely hypertensive patients can buy themselves many more healthy
years. It's that simple transaction--vigilance for life span--that makes blood pressure so worth controlling. There are many
diseases that resist everything science can throw at them. This is one you can beat. --With reporting by Melissa
August/Washington, Alice Jackson Baughn/New Orleans, Paige Bowers/ Atlanta and Leslie Whitaker/C