IMPROVED COUNTER-REGULATORY HORMONAL AND SYMPTOMATIC RESPONSES TO HYPOGLYCEMIA IN PATIENTS WITH INSULIN-DEPENDENT DIABETES-MELLITUS AFTER 3MONTHS OF LESS STRICT GLYCEMIC CONTROL

This study of patients with insulin-dependent diabetes mellitus (IDDM) and hypoglycemia unawareness examines the effect of a period of less strict glycemic control on the defective counter-regulatory hormonal r esponses to and impaired awareness of hypoglycemia. In seven patients with IDDM with strict glycemic control and hypoglycemia unawareness, r esponses were studied with the use of a hyperinsulinemic hypoglycemic clamp test before and after 3 months of test treatment, which aimed at increasing daily mean blood glucose levels to 8 to 10 mmol/L, based o n self-monitoring four times per day. The 3 months of test treatment e levated the patients' levels of glycosylated hemoglobin HbA(1c) from a mean of 6.9% (standard error [SE] 0.3%) at baseline to 8.0% (SE 0.3%, p < 0.05) and decreased the number of episodes of hypoglycemia (blood glucose level less than 3.0 mmol/L) per patient from a mean of 4.7 (S E 1.3) per week to 1.9 (SE 0.5) per week (p < 0.05). Although the same nadir (2.2 mmol/L) and duration of hypoglycemia were reached during e ach of the two clamp tests, the scores for sweating and lack of concen tration were improved (p < 0.05) at the second test. The release of gr owth hormone and epinephrine during hypoglycemia were significantly im proved (p < 0.05) at the second test, whereas the glucagon, cortisol a nd norepinephrine responses were unchanged. There were no significant differences in the results of the autonomic and cognitive function tes ts between the two tests. The results suggest that impaired hormonal a nd symptomatic responses to hypoglycemia in IDDM can be partially reve rsed by a modest rise in glucose levels for 3 months.