DEAR DR. DONOHUE: Please explain angina. I have it. I am under the impression that it is one step before a heart attack. Am I right? My father had angina and lived only three months after he was told what he had. He had a massive heart attack. I am concerned about this. What lies ahead for me? – R.T.

ANSWER: Angina is chest pain described as a squeezing or pressure sensation that comes on when a person is active, in a particularly stressful situation or is out and about in very cold weather. The pain leaves when the activity stops, the stress is relieved or the person becomes warm. The pain is felt in the chest, but it can spread to the shoulder, the arm or the neck.

Angina is a sign that the heart isn’t getting enough blood to support the stress, emotional or physical, that it must endure. It is the cry of a breaking heart. The cause of decreased blood flow usually is a buildup of cholesterol, fat and other material in the heart arteries.

Angina is quite treatable. It’s not a prelude to an inevitable heart attack if measures are taken to increase blood flow to the heart muscle. People with angina have to adopt programs that increase blood flow through clogged arteries. They have to lower their cholesterol, keep their blood pressure at desirable levels and take part in physical activities prescribed by their doctors. They take medicines that ease the heart’s burden and that open up clogged arteries. They might need angioplasty, the procedure where a doctor threads a balloon-tipped soft tube to the point of artery obstruction and then inflates the balloon to squash it.

I don’t know when your dad died, but I’m sure it was at a time when the opportunities that now exist for angina patients were not available.

The booklet on coronary artery disease, the basis of angina, explains the ins and outs of this common problem and what can be done for it. Readers can obtain a copy by writing: Dr. Donohue – No. 101, Box 536475, Orlando, FL 32853-6475. Enclose a check or money order (no cash) for $4.75 U.S./$6 Can. with the recipient’s printed name and address. Please allow four weeks for delivery.

DEAR DR. DONOHUE: I am 58 and have borderline hypertension. Recently I developed bubbles in my urine. Internet information indicates that I could be suffering from chronic kidney failure. If you have any advice, please let me know. – P.B.

ANSWER: When liquid from a height is poured onto another liquid, bubbles form. That’s normal. But when urine bubbles form to the extent that they look like a head of beer, that’s abnormal. It can be a sign of protein in the urine. Urine protein indicates kidney damage, but not always kidney failure.

A simple urinalysis is an inexpensive test that detects urinary protein.

DEAR DR. DONOHUE: You recently wrote about the immune system. It’s my understanding that the immune system is not fully formed at birth and continues to develop for several months. Breast milk encourages its development.

There is an entire generation, approaching middle age, whose mothers were told that bottled formula was just as good as breast milk. This is also the group who in young adulthood experimented heavily with marijuana, which has been reported to damage the immune system.

This double whammy, as well as the reduced exposure of babies to a normal environment, makes people more vulnerable to infections.

What is your opinion on this? – E.M.

ANSWER: My opinion is that there is no substitute for mother’s milk. It doesn’t exactly stimulate the immune system, but it contains antibodies that protect infants against many illnesses that can strike newborns. I concur with you on that.

I do not know how greatly marijuana affects the immune system or for how long the effect lasts, if there is such an effect.

Babies kept in a perfectly germ-free environment don’t develop the immunity they would in the normal world.

Dr. Donohue regrets that he is unable to answer individual letters, but he will incorporate them in his column whenever possible. Readers may write him or request an order form of available health newsletters at P.O. Box 536475, Orlando, FL 32853-6475. Readers may also order health newsletters from www.rbmamall.com