If you have diabetes, how tightly should you control your blood sugar levels? "Tight control," keeping your blood sugar levels as close to normal as possible, has been a bedrock principle in managing diabetes, as long as you avoid dangerously low blood sugar (hypoglycemia).
Long-term glucose control is measured with a glycohemoglobin A1C blood test. Many doctors recommend a maximum result of 7 percent (which translates to a glucose level averaging 135 mg/dL overall for the previous three months) or even 6.5 percent (average glucose of 120 mg/dL for the prior three months).
Earlier this year, however, a study from the ACCORD project (Action to Control Cardiovascular Risk in Diabetes) found that tight control of glucose (glycohemoglobin A1C averaging 6.4 percent vs. 7.5 percent in the standard treatment group) actually increased patients' risk of death by 22 percent. Although the results sound alarming, experts said they probably didn't apply to the general diabetes community because many of the subjects were high-risk, which can make hypoglycemia more dangerous.
Other recent studies back up the benefits of tight blood-sugar control:
- In a follow-up to the landmark United Kingdom Prospective Diabetes Study, patients with type 2 diabetes who tightly controlled their glucose in the first decade after diagnosis (glycohemoglobin A1C averaging 7 percent vs. 7.9 percent in the standard group) had a reduced risk of heart attack and death years later. Doctors called this long-term benefit a "legacy effect" of early tight control of glucose. "Now, I can go back to my clinic and tell my patients that even though they are not perfect, the good control they have achieved will have long-lasting effect," said researcher Ping H. Wang, M.D.
- Intensive glucose control (glycohemoglobin A1C averaging 6.5 percent vs. 7.3 percent in the standard group) decreased patients' risk of developing kidney disease by 21 percent, according to an international project called ADVANCE (Action in Diabetes and Vascular Disease).