One-third of American women have hypertension. Even more alarming is that after age 45, more than 50% of women have hypertension. For black women, the statistics are worse: 80% have hypertension after age 45. Hypertension is the most important risk factor for stroke. One-third of women with hypertension don’t know they have it. Of those diagnosed with hypertension, less than 25% are controlled. Since most women don’t have any symptoms associated with hypertension, they may not think it is important to lower blood pressure.

Hypertension is defined as a blood pressure greater than 140/90 – the top number is the systolic blood pressure and the bottom number is the diastolic blood pressure. Doctors used to think that the diastolic blood pressure was more important to bring down than the systolic blood pressure, but we now know that the reverse is true. Hypertension damages the arteries and worsens the damage already done by abnormal cholesterol levels which narrow arteries.

No one is sure what causes high blood pressure, although it is associated with weight gain, smoking and excessive salt intake. The estrogens released by your ovaries keep blood pressure low, which is probably why blood pressure tends to rise during the perimenopause in your 40’s. Unlike your own naturally-produced estrogens, the high levels of estrogen in birth control pills may raise blood pressure, especially if you smoke. Women who smoke or have hypertension who take the birth control pill are at high risk for stroke. Even the so-called low-dose birth control pills are associated with stroke.

Hypertension not only worsens the narrowing in the arteries produced by LDL, the bad cholesterol, but it damages the tiny arteries in your kidneys. The arteries are very delicate and when the blood pressure is hammering them, they form scar tissue and leak proteins. If the blood pressure is not controlled over time, the kidney function deteriorates and may eventually require dialysis to remove the toxins in your blood that the kidneys can longer do. More women than men end up on dialysis.

In addition to worsening narrowed arteries and destroying arteries in your kidneys, hypertension can lead to heart failure. There are two types of heart failure. In the first type, heart attacks have destroyed the heart muscles and replaced them with scar tissue, so that the heart is like a stretched-out baggy balloon that is too weak to pump blood. In the second type of heart failure, which is a result of hypertension, the very high pressures in your blood cause the walls of the heart to thicken. Thick walls make it difficult to pump blood forward, so it backs up into your lungs, which fill up with fluid and make it hard to breathe. The second type of heart failure is more common in women and very under diagnosed. Your doctor can find clues to the thickened enlarged heart on your EKG, and it can be diagnosed by an echocardiogram, an ultrasound of your heart.

Hypertension is reversible in many women, and the strategies to lower blood pressure are similar to those to lower cholesterol:

1. Lose weight. The lower your weight, the lower your blood pressure.

2. Exercise. Even if you don’t lose a pound, exercise drops your blood pressure.

3. Eat lots of fruits and vegetables. People who eat at least five servings of fruits and vegetables have significantly lower blood pressures than people who eat one serving. Fruits and vegetables are full of minerals like potassium, calcium and magnesium. Unlike sodium, these minerals cause the arteries to relax and lower blood pressure. We concentrate on increasing calcium in the diet, but magnesium is at least as important. Nuts, especially almonds, are high in magnesium.

4. Avoid sodium. Our foods in this country are extremely salty. Many women retain salt, and where salt goes, water follows. If you have more water in the tank, the pressure goes up. Eating fruits and vegetables, which contain high levels of potassium, calcium and magnesium, actually drives sodium out of your body.

If you have hypertension, you should do the following:

• Take your medications faithfully at the same time every day. Ask your doctor what your ideal blood pressure is, not what a “normal” blood pressure is.
• Check your blood pressures at home with a blood pressure monitor. Consumer Reports states that Omron Blood Pressure machines are the best.
• If your blood pressure is high in the office, it will be high in other situations – don’t make the mistake of thinking that “white-coat hypertension” is unimportant.
• Ask your doctor for an EKG.