Dr. Keith Roach: Metformin treats insulin resistance in diabetes
Dear Dr. Roach: My friend’s wife, who is 70, has a fasting glucose level of about 200. She is perhaps 40 pounds overweight with blood pressure of around 145/80. I don’t think she eats too many carbohydrates. She does take a lot of nutritional supplements. How long would it take a drug like metformin to drop her level to around 100? She has sciatica in her left leg, so she can’t exercise.
Dear R.L.: Type 2 diabetes, the type treated by metformin, is primarily about resistance to insulin. It is usually, but not always, associated with being overweight or obese. Metformin works by preventing the liver from making sugar, so the insulin that the body makes is directed at food. Metformin tends to help people lose weight, which further helps the insulin resistance and lowers average blood sugars.
Diabetes control is most commonly measured by the percentage of glucose on a particular hemoglobin molecule. This is referred to as the Hb A1c, and a normal level is below 6.2 percent, or roughly an average blood sugar of 130. An average blood sugar of 200 would correspond with an A1c of 8.5 percent — a level associated with a higher risk of heart disease, kidney disease and eye disease.
Metformin tends to reduce A1c levels by about 1.5 percentage points after six months or so. If your friend’s wife has a typical response, her A1c would drop to about a level of 7 percent, and that is a reasonable goal. An average blood sugar of 100 is an A1c of about 5 percent, and that level has a higher risk of heart disease than an A1c nearer 7.
Dear Dr. Roach: My daughter smokes. She doesn’t have COPD now, but in the spring she had bronchitis and was off work for a week. When she went back to work, didn’t feel good, and her doctor told her she had pneumonia in both lungs. She still takes cough syrup under doctor’s orders.
Dear N.P.: Getting someone to quit smoking is a challenge, but perhaps some advice I can give your daughter might help. The first piece of advice is that a cough necessitating cough syrup on a routine basis indeed might be a sign of COPD. There are two major forms of COPD: emphysema and chronic bronchitis. The definition of “chronic bronchitis” is a productive cough for three months in each of two successive years.
The second piece of advice is that quitting before there are serious symptoms is the best time to quit. Although the body has some ability to recover from the effects of chronic cigarette smoke, there is a degree of permanent damage in long-term smokers. Quitting greatly slows down that rate of damage to the lung and cuts the risk of having lifelong symptoms of shortness of breath and cough.
Readers may email questions to ToYourGoodHealth@med.cornell.edu.