Tuesday, May 1, 2012
Can I “feel” my high and low blood sugars reliably?
Although many people with diabetes confidently state that they can reliably detect both their high and low blood sugars without actual measurement, studies have shown that these beliefs are not usually accurate. It is generally easier to be aware of hypoglycemia (“low sugars”) than high blood sugars. This is because the margin of safety between blood sugars in the lower part of the normal range and dangerously low blood sugars is quite narrow—only about 25 mg/dl—and the body has a vigorous and rapid response system, designed to ensure that a source of energy is rapidly found and consumed. Nevertheless, especially after longstanding diabetes or a period of very tight glucose control, symptoms of low blood sugar are often not detected by patients. If they are detected, they are perceived with insufficient time to take preventive action. Typical early symptoms of hypo- glycemia are shakiness, sweatiness, hunger, abdominal discomfort, palpitations (i.e., a fluttering sensation in the chest), and headache. When blood sugar is very low, confusion and disorientation often occur together with sometimes bizarre behavior, but these features are generally noted by others rather than the affected person him- or herself. In the case of hyperglycemia, people with diabetes are usually quite unaware of the presence or severity of high sugars until secondary symptoms such as frequent urination and thirst occur. For the great majority of people, the only sure way to detect high blood sugar is to perform regular glucose monitoring.