Diabetes won’t be controlled by drugs alone

DEAR DR. ROACH: My sister, 73, has Type 2 diabetes, and is taking 500 mg of metformin twice a day.

After two years on metformin, her fasting glucose level is only 125 mg/dl and A1C only 6.8 per cent.

If she continues taking medication, will her fasting glucose level ever get to around 85 mg/dl and her A1C get to five per cent? She wants to be in the normal ranges.

ANSWER: Type 2 diabetes mellitus is a common disorder of unknown exact cause, but which generally is caused by resistance to the action of insulin and by a gradual decrease in the amount of insulin the pancreas is able to put out.

There are many types of treatment for diabetes, but the most important are a healthy diet and regular exercise (a registered dietician nutritionist is a valuable source of information).

In people who need medication, metformin is a good first choice for many, especially people who are overweight.

The goal of treatment is the control of symptoms, but also to reduce the risk of complications of diabetes, especially blood vessel disease.

Small blood vessel disease leads to kidney failure, nerve damage and vision changes.

Large blood vessel disease leads to heart attack, stroke and peripheral vascular disease, which sometimes can mean amputations.

There remains debate about the optimal blood sugar goal. For older people and those at high risk for (or who already have) large blood vessel disease, treating people with a goal A1C level of five per cent actually has more risk than a goal of around seven per cent.

However, for younger people, most diabetes experts recommend an A1C level in the “normal” range, such as 5-6 percent.

Achieving that requires dedication, meticulous care of diet and exercise, and often multiple medications.

DEAR DR. ROACH: I am a 79-year-old male who has been diagnosed with Parkinson’s disease, and my neurologist wants me to have an MRI done on my brain.

I have dental caps, fillings and a titanium post for an implant in my mouth and am wondering if you could address the risks involved in having the MRI done with these.

I also am concerned about the possible effect of the MRI on a freckle on my left retina that my ophthalmologist has been watching for years.

If you could enlighten me on the likelihood of adverse reactions to dyes used in MRI and their effects, I would appreciate information on that issue as well.

ANSWER: Dental caps can be made of ceramic or metal (or a combination) and, like dental fillings, can cause small areas of image distortion, which should not be an issue when looking at the brain. They are safe in an MRI machine.

Titanium is not much affected by the MRI either, and so it should be safe.

The MRI will not affect the pigment (freckle) on the retina.

The dye used for MRI scans is normally gadolinium, which is safe. Serious reactions occur in about one person per 100,000 who takes it, and include allergic-type reactions, such as itching and hives.

Recent evidence suggests that a small amount of the contrast remains in the body for a prolonged period; however, the significance of this is uncertain. Nonetheless, MRI contrast should be given only when it’s of significant benefit to do so.

DR. ROACH WRITES: A recent column from a man asking for alternatives to coronary bypass surgery generated many letters with the same question: Why not advise a change in diet as an alternative to surgery?

There are two reasons. The first is that it’s not an alternative to surgery: It’s a medical recommendation that should be made for every person with diagnosed coronary disease. Nearly all people can improve their diet. While a vegan diet was the most common recommendation I received, it still is not clear that a vegan diet is most likely to reduce coronary disease.

In the vast literature on diet, there are only a few well-done studies that show a benefit.

The clearest benefit has been from the Mediterranean diet, but a very-low-fat, plant-based diet, in combination with stress reduction and smoking cessation, has been shown to help reverse coronary lesions.

The second reason is that if someone needs the arteries in his or her heart reopened, the changes in diet are not likely to reverse blockages in the time needed to prevent a heart attack.

Healthy diet changes are appropriate for all people with heart blockages, but inadequate by themselves in the short term, in people with symptoms of angina and serious blockages.

Dr. Roach s unable to answer individual letters, but will incorporate them in the column when possible. Readers may email questions to ToYourGoodHealth@ med.cornell.edu or request an order form of available health newsletters at 628 Virginia Dr., Orlando, Fla., U.S.A., 32803.