Hypoglycemia Common Even With High A1C

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Miriam E. Tucker is a senior writer with Elsevier Global Medical News. ORLANDO – Hypoglycemic episodes were common despite high hemoglobin A1c levels among 40 elderly community-living adults with diabetes who underwent continuous glucose monitoring. “Raising A1c goals may not be adequate to prevent hypoglycemia in this vulnerable population,” Medha N. Munshi, MD, said at the annual scientific sessions of the American Diabetes Association. Guidelines from the American Diabetes Association and the American Geriatric Society advise that the usual recommended HbA1c target of less than 6.5%-7.0% might be relaxed for elderly adults who have a history of severe hypoglycemia, limited life expectancy, advanced diabetes complications, or extensive comorbidity (Diabetes Care 2010;33 [suppl 1]). In practice, this has been interpreted as a goal of less than 8%. But no study has ever clearly demonstrated that raising the HbA1c target actually reduces the risk of hypoglycemia, said Dr. Munshi, director of the Joslin Diabetes Center geriatric programs at Beth Israel Deaconess Medical Center, Boston. The current study included patients older than 69 years (mean, 75 years) and with a HbA1cgreater than 8%. The patients took a mean of eight medications per day, with 55%) on insulin alone and another 38% on insulin plus one or more oral agents. Two-thirds had type 2 diabetes, and the rest had type 1. Patients performed four fingerstick glucose measurements per day and kept daily diaries of hypoglycemic symptoms, diet, and physical activity. One or more hypoglycemic events occurred in 26 of the 40 patients. The 26 patients who experienced hypoglycemia (glucose less than 70 mg/dL) did not differ from the 14 without such events in patient characteristics including age, diabetes duration, HbA1c, or insulin treatment. There was also no difference between those who did and did not have hypoglycemia in cognitive dysfunction, depression, falls in the past 6 months, number of medications, hypertension, or vision/hearing problems. Of the 26 with hypoglycemia, 12 had HbA1c levels above 9%. “Even a high A1c doesn't preclude lows. Hemoglobin A1c measures the mean. There are wide fluctuations in this population,” Dr. Munshi noted. Surprisingly, 58% of the study's 102 hypoglycemic episodes occurred among the 16 patients with type 2 diabetes, with a mean duration of nocturnal hypoglycemia nearly twice that of the hypoglycemia in the type 1 patients (2.9 vs. 1.6 hours). “Even the type 2 patients had wide glycemic excursions,” she said. Also of concern, 95 of the 102 episodes (were not recognized by fingerstick testing or by the patients' symptoms. Moreover, there was no significant relationship between severity of hypoglycemia and age, type of diabetes, duration, HbA1c, treatment, or living alone. “I believe that elderly patients with other comorbidities are unable to follow complex insulin regimens appropriately and end up having wide fluctuations in their glucose values. If a treatment regimen is designed with consideration for an elderly patient's self-care abilities, risk of hypoglycemia can be reduced,” Dr. Munshi said in an interview. In nursing home settings, education of nursing staff to adapt insulin regimens to changes in overall health, fluctuating appetite, and physical activity – for example, by holding short-acting insulin if the patient refuses a meal – is probably the best way to avoid large fluctuations, she commented. And when available, CGM can be extremely helpful for elderly patients. “I think CGM can be a great tool for pattern recognition and assessment of risk of hypoglycemia in elderly patients who are on complex insulin regimens without consideration of glycemic control,” Dr. Munshi said. This study was funded by the American Diabetes Association. Dr. Munshi stated that she had no conflicts of interest.