High blood pressure -- hypertension -- is a "gotcha."
You can have it and maybe not feel so bad.
You can have it for quite a while and not even know it.
You can know about it and forget to take your medicine. . . .
And then . . . whammo.
Now everybody needs blood pressure, of course, that is how the blood circulates after the heart pumps it into the arteries.
Measurable blood pressure is the pressure of the blood against the artery wall: while the heart is pumping (the systolic, or higher number) and when it is resting (the diastolic, lower number).
The arteries are elastic, constructed to contract and expand to help the river of blood along its way, transporting oxygen and nourishment to the rest of the cells in the body and carrying away wastes.
The arteries are lined with a delicate membrane, however, which can be injured easily. The resulting scar tissue can be a collecting point for debris (plaque) which can build up until the artery is blocked.
Even the turbulence caused by high blood pressure itself can injure this delicate membrane, creating a vicious cycle.
As the artery is narrowed, the pressure is increased. Scientists use the metaphor of a hose nozzle. A number of physiological events, not all of them clearly understood, can cause the arteries to constrict with the same effect. It may be one of a number of hormones or it may be an increase in the volume of blood in the body -- which occurs, for example, when fluids are retained.
When arteries are so narrowed that no blood can get through, a stroke is the eventual result. If it is a coronary artery, the result is a heart attack.
When the heart must pump, day after day after day, against increasing pressure in the arteries, the heart will be damaged and eventually will fail.
The bottom line is this: People with high blood pressure are the best candidates for heart attacks, congestive heart failure and strokes, even without having had a recognizable symptom in advance.
There is still a lot the medical community does NOT know about hypertension. Its causes, in many cases, are shrouded in mystery and controversy.
In the burgeoning field of behavioral medicine, experts believe there has been demonstrated a clear relationship between hypertension (and resultant cardiac diseases) and environmental stress.
The so-called A-type personality -- driven, ambitious, workaholic, intense -- is often more likely to demonstrate the inappropriate fight-or-flight response which sets the hormones flowing, causing blood pressure to shoot up. Although blood pressure drops from stress-induced peaks, it often stays higher than it had been before, leading to that state of chronic hypertension that can be so dangerous.
Many traditionalists in medicine are not prepared to accept this thesis fully, and even less ready to accept relaxation techniques, biofeedback and other anti-stress measures as legitimate blood-pressure controls.
Dr. Edward D. Freis, one of this country's preeminent experts in hypertension and a strong traditionalist, flatly calls relaxation techniques "phony" and decries the lack of controlled test results.
lDr. Freis' work as teacher, clinician, author and researcher has been focused on identifying and then controlling hypertension.
It is a chronic ailment that never goes away, but in most cases it can be controlled fairly simply -- by diet, by a combination of diet and an ever increasing pharmacopeia of effective drugs or, in some cases, by drugs alone, ranging from mild diuretics with minimal side effects to powerful and sometimes hard-to-tolerate substances.
Studies have shown that the rate of deaths from heart attacks can be halved if even borderline high blood pressure is controlled and the incidence of strokes reduced to about one-fifth.
Congestive heart failure -- caused six times more often by hypertension than by rheumatic heart disease -- for example, can be virtually eliminated by blood pressure control.
"It has been estimated," says Dr. Freis, "that there are 60 million people out there with high blood pressure -- either borderline, mild or severe. "Think," he says, "of the populations of New York, Boston, Philadelphia, Baltimore, Washington. . . ." (Maybe 20 million people. Nowhere near 60 million)
"The thought," says Dr. Freis, "of 60 million people on drugs is, well, alarming."
For the 20 million or so Americans with mild hypertension, Dr. Freis would recommend a drug-free regimen unless multiple risk factors are present.
This means, by and large, two major dietary adjustments which, he says, are more easily said than done:
Losing at least 20 pounds (and keeping it off).
Virtually eliminating salt from the diet.
"What I think is needed," sighs Freis, "is a lot of research on how to get people to comply."
Meanwhile, Dr. Freis, who is connected with Georgetown University Medical Center and the Veterans Administration Hospital here, is involved in a number of studies -- each involving multiple hospitals and about 500 patients.
These include tests on new drugs, investigations into hypertension control in the aged and research that will try to determine if medicine can be reduced after it has brought hypertension under control, to find, if possible, a minimum effective dose.