It’s a choice between two evils

Dear Dr. Gott: I’m hearing a great deal about so-called “virtual colonoscopy.” The procedure appears to be an accurate substitute for standard traditional (optical) colonoscopy. Is this a medical breakthrough?

Dear Reader: Not yet.

Virtual colonoscopy is simply another option. It has its benefits and its problems.

The concern about a standard colon study include discomfort, the nuisance of bowel-cleansing preparation, and the risk of colonic perforation with the fiber-optic scope.

The disadvantages of virtual (X-ray) colonoscopy include pre-treatment to clean the bowel, substantial exposure to radiation, and the inability to biopsy or remove significant lesions.

Granted, the optical X-ray procedure is less invasive. However, the preparation is an annoyance, the procedure may be uncomfortable, and the results could require further attention, such as standard colonoscopy with biopsy.

This topic was recently reviewed in the Feb. 14, 2005, issue of “The Medical Letter.” The authors conclude that the meager benefits of virtual colonoscopy are far outweighed by the benefits of traditional colonoscopy.

Therefore, I reiterate the concerns that I expressed earlier: Until virtual colonoscopy has been further refined, patients (and their physicians) should rely on the traditional procedure, which should – in most instances – start at about 50 years of age. Patients with family histories should, for obvious reasons, be tested earlier. And, depending on the findings (polyps or no), the testing should be repeated every 5 to 10 years.

Dear Dr. Gott: In a recent column, you stated that the niacin pills used for lowering cholesterol can cause liver inflammation. My doctor has never heard of this side effect, but I stopped the niacin anyway. Now I am confused about what to do.

Dear Reader: In doses sufficient to reduce cholesterol levels, niacin may cause – as a relatively uncommon side effect – liver inflammation. This can easily be monitored with a blood test in conjunction with patients’ regular cholesterol blood tests. The side effect is rare at low niacin levels but climbs, depending on how much insulin is ingested. Most patients start with 500-mg pills twice a day. Ideally, that dosage should be doubled to achieve maximum benefit. That’s when complications of niacin therapy, similar to those of “statin” prescription drugs, may become a problem.

I advise you to restart your niacin at 500 mg twice a day and gradually increase the dose (with your doctor’s approval) in a few weeks. Then get a liver blood check. You may be one of those lucky people who can take significant amounts of niacin without bad consequences.

If not, then other therapy may have to be considered.