DEAR DR. DONOHUE: My husband is 45, 6 feet 2 inches tall and weighs 240 pounds. He has a horrible family heart history. His father had to have a heart transplant. I persuaded him to have a physical this year. He has high cholesterol and high blood pressure. His doctor encouraged him to make some lifestyle changes, like stopping chewing tobacco, losing weight and limiting his alcohol intake. He also has erectile dysfunction.

He’s a restless sleeper, snoring and feeling extremely unrested during the day. His doctor had him take an overnight oxygen test, which showed that his oxygen dropped dangerously low, suggesting sleep apnea. We heard a heart doctor say that sleep apnea is a factor in high blood pressure and erectile dysfunction. Can this ever be fixed? – T.H.

ANSWER: Your husband needs to get a definite opinion about sleep apnea. The diagnostic tests can be done at home or can be done in a specially equipped clinic.

Sleep apnea is a condition where there are periods of no breathing (apnea) during sleep. Quite often the affected person snores with increasing, ear-splitting loudness until the no-breathing episode arrives. Then there is eerie silence until breathing restarts with a gasp or grunt. The apneic spell lasts at least 10 seconds and recurs five or more times every hour. Consequences of sleep apnea can include daytime drowsiness, a rise in blood pressure, erectile dysfunction, elevation of lung blood pressure, heart failure and personality changes. He must lose weight, and he must decrease his alcohol intake. Excess weight leads to flabby throat tissues, and those tissues obstruct the flow of air into the lungs – the prime defect of sleep apnea. Alcohol relaxes throat tissues to produce the same effect. A mask that delivers air under pressure to the nose (a CPAP – continuous positive airway pressure machine) can often reverse sleep apnea. So can procedures that widen the throat through removal of redundant tissue with a scalpel or with a laser. If things don’t improve with treatment for sleep apnea, write me again.

DEAR DR. DONOHUE: I have a hard, little lump on the underside of my wrist. The doctor says it’s a ganglion cyst and not to worry about it. I looked up ganglion in the dictionary and it says “a cystic tumor.” Tumor? So, now I’m worried. Should I be? – M.D.

ANSWER: A ganglion is a soft lump, most often jutting out from the back of the wrist. They don’t usually hurt.

“Tumor” is a word that carries bad implications for people. It means any swelling. Some tumors are cancerous. Ganglions are not. It’s just a swelling that sprouts from a tendon covering or from a joint covering and that is filled with a jellylike material.

If a ganglion is large, limits motion, is painful or is a cosmetic problem, a doctor can remove it without a great deal of fuss.

DEAR DR. DONOHUE: I have leukopenia and would like information on it. My hematologist did a bone-marrow test, and it was OK. Do I need to be concerned? I am having my blood count checked every six months. – M.S.

ANSWER: Leukocytes (LUKE-oh-sites) are white blood cells, the body’s armed forces. They fight germs, participate in immune defenses and produce antibodies — the body’s artillery shells.

Leukopenia is a decreased number of white blood cells. The consequences of that depend on how low the white count has dropped. The normal white blood cell count is 4,300 to 10,800.

There are five varieties of white blood cells, and the two most important ones are granulocytes and lymphocytes. Ordinarily, the focus is on granulocytes, since they are the ones that are most involved in fighting germs. I assume they are the ones whose numbers have dropped in you. If the granulocyte count is less than 1,000, infections are common. The lower the number falls, the greater the risk of infection.

Some people have a slightly lower-than-normal count but do not suffer from repeated infections. This fits your situation. You have had a bone-marrow test, the most important test in detecting serious white blood cell aberrations. Your test was normal. Simply following your counts is a sensible way to approach your problem.

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