HEART PROBLEMS: BLOOD CLOTTING AND TONIC WATER

Spontaneous clotting of blood in the circulation will cause a stroke (if the clot lodges in one of the brain’s blood vessels) or a heart attack (if it blocks one of the heart’s coronary arteries). To prevent recurrences, many people recovering from a stroke or a heart attack are given daily doses of one of the anticoagulant drugs, such as Warfarin or Coumadin. Other conditions, too, (e.g., heart valve abnormalities) may require long-term anticoagulation. Since too much drug will result in bleeding, and too little of it provides no benefit at all, regular testing is required to make sure that the patient’s dosage needs are being exactly met.

Change in dosage requirement could occur in anyone who drinks tonic water, a major ingredient of which is quinine. Quinine, reports the British Medical Journal (286:1258), interacts with anticoagulants, making their effect more powerful. Anticoagulant users, therefore, should be careful to avoid any drinks that are made with tonic water.

*149\143\2*

SUNLIGHT AND EYE PROBLEMS

Malignant melanoma, a cancer that grows from pigment cells either of the skin or of the eye, is about three times more common in our southern states than in the North, the New England Journal of Medicine (313:789) reports, and the factor responsible seems to be the ultraviolet light in sunshine.

Not surprisingly, therefore, people with brown eyes (whose eyes are protected by the pigment) are only about half as likely as those who are blue-eyed to develop a melanoma of the eye. Furthermore, those who do develop this cancer are likely to have spent more time farming, gardening, or sunbathing outside, or tanning indoors with a lamp. Lastly, the report indicates the importance of protecting our eyes with a hat, visor, or sunglasses, which, if used routinely, reduce the risk of eye cancer by about 50 percent. Clearly, therefore, sunlight is a big factor in eye cancer, but one we can largely avoid. UV-filtering sunglasses should be worth their extra cost!

Sunlight is also an important factor in the development of cataracts, the Western Journal of Medicine (143:511) reports. Ultraviolet light (UV) causes the deposition of minute granules of an opaque brown pigment in the normally clear and colorless body of the lens. After many years, if the eyes continue to be exposed to strong sunshine, more and more granules are deposited until the lens becomes completely opaque, with blindness as a result. Vision can be instantly restored, of course, by surgically removing these cataracts and replacing them with artificial lenses. The more we expose our eyes to UV, it has been found, the more opaque our lenses become. Not surprisingly, therefore, cataracts are much more common in the tropics than in the temperate zones of Europe and North America. Furthermore, they are less common in office workers than among people who work outside.

Along the same line, the British Medical Journal (65:869) reports that in the tropics people need reading glasses at an earlier age than they do in a cold climate. The average age at which glasses are first needed varies from 36 at one climatic extreme to 50 at the other. Again, stronger light could well be the factor involved, and people should be careful to wear sunglasses when exposed to bright sunlight.

*118\143\2*

PROSTATE CANCER TREATMENT

Enlargement of the prostate, whether due to cancer or to the benign swelling that occurs so commonly in aging men has, until recently, been most often treated by the operation in which pieces of tissue are removed with an instrument that is passed up the urethra, the urinary passage in the penis. Called transurethral resection (TUR), this is easier than surgically removing the entire prostate through the lower abdomen, an operation known as prostatectomy. Furthermore, until now, TUR was much less likely than prostatectomy to cause impotence because it does not injure nerves supplying the penis. Prostatectomy, as usually performed, did injure those nerves, thereby often causing permanent impotence. Understandably then, even though cure of prostate cancer is less likely with TUR than with prostatectomy, TUR has been the more popular procedure.

Now, thanks to a new type of prostatectomy operation that has just recently been developed at Johns Hopkins Hospital and reported in Prostate (4:473), we can at last have the best of both worlds.

Because it spares the nerves of the penis, this new operation is most unlikely to cause lasting impotence. (For some weeks or months after prostate surgery of any kind, it must be understood, all men will experience at least some degree of impotence). Another advantage of the new prostatectomy surgery, which is performed through the lower abdomen, is the completeness with which it removes all tumor tissue. With these positive features, it is likely to become the treatment of choice.

*85\143\2*

PREVENTABLE BLINDNESS

In senile macular degeneration (SMD), new blood vessels grow over the retina (the light-sensing layer in the back of the eye), distorting it so that it no longer functions properly. Although SMD accounts for nearly all new cases of blindness in people over 65, its cause remains unknown.

Nevertheless, physicians working at the National Eye Institute have made an exciting announcement. A brief session in the doctor’s office with about 10 minutes of laser beam treatment usually stops the blood vessel proliferation and restores normal vision in over 80 percent of cases. Most of the remainder benefit, too, but partially. Many people need this treatment repeatedly.

The researchers announcing this advance in Archives of Ophthalmology (100:911) make it clear that, to benefit, SMD patients must obtain laser treatment soon after the onset of symptoms. If they wait too long, irreversible damage will already have been done. To catch SMD recurrences early enough, the researchers urge, all victims should test their own vision daily with an Amsler grid (which they can get from an ophthalmologist), and report changes right away.

*54\143\2*

WATER PILLS AND SUNLIGHT

Certain drugs have the ability to induce an allergic hypersensitivity to sunlight, a side effect known as phototoxicity. Perhaps the most common medicines to do this are the thiazide diuretics (“water pills”) that so many people rely upon for the control of high blood pressure or heart failure.

Phototoxic effects in the skin include itching and a red, bumpy rash (due to many small blisters) on parts of the body exposed to sunlight. When the drug is stopped right away, the rash may quickly disappear, even if it continues to be exposed to the sun. However, if the drug is ever given again, the rash quickly returns and will continue to cause discomfort for the rest of the person’s life whenever he or she is exposed to sunlight.

In such cases, it may be possible to shield the skin with PUVA (an artificial deep suntan). To do this, the Archives of Dermatology (121:522) reports, dermatologists give an artificial vitamin A-like drug by mouth that, after it is absorbed, darkens the skin in the presence of ultraviolet light (UV), while they administer graded doses of UV. Without such treatment, people who have chronic phototoxicity must permanently avoid the sun.

*23\143\2*