Dear Dr. Roach: I am a 77-year-old woman in good health. Recently, I donated blood for the first time in 20 years. Since then, the American Red Cross has contacted me several times to donate platelets because I have so many of them in my blood. My question is, since so many of my relatives have died of heart problems, could having a lot of platelets increase my chances of blood clots that could lead to stroke or heart attack?
Dear P.N.: First off, I would have to know if your platelet count is normal or abnormal. With normal platelet count, you can donate platelets very frequently — the American Red Cross says up to 24 times per year. Platelets are removed from the blood during donation, and you keep the rest of the blood components. It appears to be the “stickiness” of the platelets, not their number, that gives the most risk of heart disease and stroke.
Abnormally high platelet counts can be caused by many conditions, but persistently high levels should raise the possibility of the condition essential thrombocythemia, also called essential thrombocytosis. (“Essential” in this case doesn’t mean “necessary,” it means “unexplained.” “Thrombo” is from the Greek word for “clot,” and “cyte” means “cell.”) Both excess bleeding and excess clotting occasionally occur with ET.
Although most ET cases don’t effect lifespan, the condition can develop into leukemia or other related diseases, and a visit to a hematologist — a blood specialist — is in order for persistently abnormally high platelet counts.
Dear Dr. Roach: From a blood test, how can I tell if I am an insulin-dependent Type 2 diabetic? For instance, what would my insulin or glucose readings have to be?
Secondly, at what point would I have to start taking medications?
Dear E.: Diabetes is diagnosed with any of the following: hemoglobin A1c of 6.5 percent or higher; fasting blood sugar of 126 or higher; blood sugar during a glucose tolerance test of 200 or greater at two hours; or random glucose of 200 or greater in someone with classic symptoms. In Type 1 diabetes, insulin levels are very low, while in Type 2 they are normal or high.
Not everybody with diabetes needs medication. Many people with Type 2 diabetes can be well-controlled just with dietary modification and often weight loss, and almost everybody with diabetes can improve with a better diet. Medications usually are given if the A1c is much greater than 7 percent and if diet, exercise and weight loss efforts have been so far inadequate.
In addition, medication often can be stopped with better control through lifestyle. Insulin-dependent Type 2 means just that — insulin is being used, along with lifestyle and often noninsulin medications.
Except in very rare instances, everyone with Type 1 diabetes needs insulin.
Readers may email questions to ToYourGoodHealth@med.cornell.edu.