Monitoring and treating high blood pressure has become so routine that it is hard to believe there's anything new to report. But it turns out there is news on this subject to which we must all pay attention or risk heart attack or stroke. What's new? Doctors have been focusing on the wrong number in looking for red flags of future illness. In particular, doctors recently have learned that it actually is systolic pressure (the top number) that is the key indicator of potential danger rather than diastolic pressure (the bottom number), which had been previously thought to be critical.

Blood Pressure Definitions

As a refresher, blood pressure has three measurements: systolic, diastolic and pulse.

Systolic pressure is the top, or first, number and measures the maximum force that blood exerts on the artery walls as the heart contracts to pump out the blood and the pressure 'wave' flows down the arterial tree. This number is always the higher one.

Diastolic pressure is the bottom, or second, number and is a measurement of force as the heart relaxes to allow the blood to flow into the heart. This is always the lower number.

Pulse pressure is the difference between the two numbers and a crucial measurement that indicates hardening of the arteries.

As for a blood pressure reading, 120/80 is considered normal... 110/60 is optimal.

Essential, or primary, hypertension, which accounts for approximately 90% of all cases, means that the condition has no known cause.

In secondary hypertension, a cause has been diagnosed. Isolated systolic hypertension is defined as a top number of over 140 but the diastolic is normal -- 90 or below. The wider the spread between the systolic and diastolic numbers, the stiffer your arteries and the greater your risk for heart disease and stroke.

The New News on Hypertension

Until now, most doctors have always thought that a high diastolic number -- 90 or above -- was most dangerous, but now we know differently. Samuel J. Mann, MD, a blood pressure specialist and associate professor of clinical medicine at New York-Presbyterian Hospital/Weill Medical College of Cornell University, explains that after looking at numerous studies that have followed patients for many years, the findings clearly show that a high systolic pressure correlates more closely with strokes and heart attacks than high diastolic pressure.

Even worse, when the systolic pressure is high but the diastolic is normal, the pulse pressure is also high, and that is a sign of arterial stiffness, or atherosclerosis. In someone with a blood pressure reading of 160/70 for instance, the pulse pressure of 90 (160 minus 70) doesn't mean this person will get stiffened arteries -- it means the condition already exists. When arteries harden, they narrow or get blocked and there is insufficient blood flow to the heart and brain, leading to heart attack and stroke.

Isolated systolic hypertension occurs primarily in people over age 50 and is a strong predictor of stroke and heart attack. (High diastolic pressure is usually a predictor of these cardiac events in people younger than age 50.)

Treatment Options

There are two ways to treat hypertension -- lifestyle changes and medication -- but Dr. Mann does not treat all forms of hypertension. For example, if a person over age 50 has isolated systolic hypertension, Dr. Mann would treat it with a diuretic (to rid the body of water) or a calcium channel blocker, particular medications designed specifically for hypertension. However, if only the diastolic pressure is high -- 120/100 for instance, indicating a pulse pressure of 20 -- Dr. Mann says he wouldn't treat this patient at all. This low number of 20 means his arteries aren't stiffening.

One problem Dr. Mann emphasized in treating hypertension in elderly people is that if blood pressure is lowered too much, it can affect cognition and balance, and he doesn't want to risk injury from falling. Low blood pressure (hypotension) is blood pressure low enough to cause dizziness and fainting. It will vary from person to person.

Lifestyle changes are the other form of treatment and the one that Dr. Mann urges first. Exercise is critical, but first should come a change in diet -- specifically, eating the DASH way. The acronym DASH stands for Dietary Approaches to Stop Hypertension, and it has proven effective for many people with hypertension.

Make a Dash to DASH

At the core of the DASH plan is a diet that is "low in saturated fat, cholesterol and total fat, and that emphasizes fruits, vegetables and low-fat dairy foods. This eating plan... also includes whole grain products, fish, poultry and nuts. It is reduced in red meat, sweets and sugar-containing beverages. It is rich in magnesium, potassium and calcium, as well as protein and fiber."

The above quote is from the 24-page booklet, Facts About the DASH Eating Plan, NIH Publication No. 03-4082 and can be ordered or downloaded on-line at http://www.nhlbi.nih.gov/health/public/heart/hbp/dash. This very informative publication summarizes two studies that prove conclusively the effectiveness of DASH, tips on how to follow the eating plan, sample recipes and a chart to monitor what you eat.

The most exciting finding about DASH is that dramatic blood pressure decreases were seen within two weeks of following this eating plan.

Supplemental Assistance

Daily Health News contributing editor Andrew L. Rubman, ND, adds that there are a number of nutritional supplements that can help improve your blood pressure. It's best to have these prescribed by a trained naturopath who should work in tandem with your physician for a fully integrated approach.

More Food Facts

One thing we do know, says Dr. Mann, is that a low-potassium diet can raise blood pressure, but he cautions against using a potassium supplement. For many, the simple solution is to consume foods rich in this mineral -- such as bananas, avocados, baked potatoes and winter squash. If you are taking medication that can affect potassium level, such as antihypertensives or diuretics, dietary changes will probably be insufficient to provide optimal levels of this mineral. If this is the case, potassium supplements may be necessary -- but only under direct physician supervision.

Additionally, according to the American Journal of Clinical Nutrition, about 2 1/2 tablespoons of sesame oil -- used in salad dressing or on vegetables -- a day "can significantly lower blood pressure, especially in people on hypertensive medication" and lower the amount of medication needed. This polyunsaturated oil can ease inflammation, which can in turn improve blood pressure.

In business, people generally don't look at single numbers but at the comparison of numbers in relation to each other. So, too, with blood pressure. Individual measures are interesting... but their interplay tells a much more meaningful story. With proper attention, your story can have a happy ending.