Unawareness of hypoglycemia by insulin-dependent diabetics.
After several years of insulin therapy, about 20% of insulin-dependent diabetics have little or no perception of hypoglycaemia because of a loss of the adrenergic warning symptoms. This defect, poorly correlated with the presence of autonomic neuropathy, has been classically explained by a defect in the catecholamine secretion. We compared the hormonal counterregulation during hypoglycaemia induced by subcutaneous injection of insulin in 7 insulin-dependent diabetics with poor perception of hypoglycaemia and experiencing repeated episodes of severe hypoglycaemia (group A) and 7 insulin-treated diabetics with very good perception of hypoglycaemia and not experiencing severe hypoglycaemia (group B). Groups A and B were similar in terms of age, duration of diabetes, HbA1c level and degenerative complications. The glucagon levels were identical and non-reactive in the two groups. The basal levels and secretion peaks of adrenaline, noradrenaline, growth hormone and cortisol were similar between the two groups, but there was a significant delay in secretion in group A with a blood glucose threshold of adrenergic secretion of between 3.1 +/- 0.5 and 1.6 +/- 0.2 mmoles/l in group A and between 4.6 +/- 0.3 and 3.2 +/- 0.2 mmoles/l in group B (P less than 0.05). This delayed secretion could be explained by desensitisation of the hypothalamic glucostat and could be due to the frequency and/or severity of hypoglycaemic episodes.
Grimaldi
A
A
Service Diabétologie, C. H. U. Pitie-Salpetriere, Paris, France.
Bosquet
F
F
Davidoff
P
P
Digy
J P
JP
Sachon
C
C
Landault
C
C
Thervet
F
F
Zoghbi
F
F
Legrand
J C
JC
D000328:Adult; D000368:Aged; D001786:Blood Glucose / Q000378:metabolism; D003922:Diabetes Mellitus, Type 1 / Q000097:blood / Q000150:complications / Q000188:drug therapy / Q000503:physiopathology*; D004837:Epinephrine / Q000097:blood; D013006:Growth Hormone / Q000097:blood; D006801:Humans; D006854:Hydrocortisone / Q000097:blood; D007003:Hypoglycemia / Q000097:blood / Q000503:physiopathology*; D007328:Insulin / Q000627:therapeutic use*; D008875:Middle Aged; D009638:Norepinephrine / Q000097:blood; D010465:Perception / Q000502:physiology; D012307:Risk Factors; D013997:Time Factors
D001786:Blood Glucose; D007328:Insulin; D013006:Growth Hormone; D006854:Hydrocortisone; D009638:Norepinephrine; D004837:Epinephrine