TY - JOUR
T1 - Hypoglycemia unawareness in IDDM
AU - Mokan, Marian
AU - Mitrakou, Asimina
AU - Veneman, Thiemo
AU - Ryan, Christopher
AU - Korytkowski, Mary
AU - Cryer, Philip
AU - Gerich, John
PY - 1994/12
Y1 - 1994/12
N2 - OBJECTIVE - To assess the characteristics of patients with hypoglycemia unawareness (development of neuroglycopenia without appropriate prior autonomic warning symptoms) and its predisposing factors. RESEARCH DESIGN AND METHODS - We studied 43 insulin-dependent diabetes mellitus patients who were objectively categorized as having or not having hypoglycemia using the stepped hypoglycemic clamp technique in which plasma glucose was clamped at plateaus of 4.3, 3.6, 3.0, and 2.3 mmol/l and a statistical criterion (onset of autonomic warning symptoms at a plasma glucose concentration 2 SD below normal) and examined their clinical characteristics and hormonal, symptomatic, and cognitive responses. RESULTS - Eleven (26%) of the patients were classified as having hypoglycemia unawareness. Compared with the other patients, unaware patients had a lower HbA(1c) level (P < 0.01), a longer duration of diabetes (P < 0.01), and a history of more severe hypoglycemia (P < 0.003). During experimental hypoglycemia, counterregulatory hormone responses, neuroglycopenic symptoms, and cognitive dysfunction all began at lower plasma glucose concentrations in unaware patients (P < 0.01, 0.03, and 0.01, respectively). Moreover, although the magnitudes of their plasma catecholamine responses and autonomic symptoms were reduced (both, P < 0.01), the plasma catecholamine levels at which autonomic symptoms began was not altered. Finally, as seen from glucose infusion rates necessary to maintain identical plasma glucose levels, patients with hypoglycemia unawareness had increased sensitivity to insulin (P < 0.001). CONCLUSIONS - Our results confirm an association between hypoglycemia unawareness and duration of diabetes, glycemic control, and occurrence of severe hypoglycemia, and in addition provide evidence that both autonomic and neuroglycopenic symptoms are affected and that insulin sensitivity is increased, but β-adrenergic sensitivity is not diminished.
AB - OBJECTIVE - To assess the characteristics of patients with hypoglycemia unawareness (development of neuroglycopenia without appropriate prior autonomic warning symptoms) and its predisposing factors. RESEARCH DESIGN AND METHODS - We studied 43 insulin-dependent diabetes mellitus patients who were objectively categorized as having or not having hypoglycemia using the stepped hypoglycemic clamp technique in which plasma glucose was clamped at plateaus of 4.3, 3.6, 3.0, and 2.3 mmol/l and a statistical criterion (onset of autonomic warning symptoms at a plasma glucose concentration 2 SD below normal) and examined their clinical characteristics and hormonal, symptomatic, and cognitive responses. RESULTS - Eleven (26%) of the patients were classified as having hypoglycemia unawareness. Compared with the other patients, unaware patients had a lower HbA(1c) level (P < 0.01), a longer duration of diabetes (P < 0.01), and a history of more severe hypoglycemia (P < 0.003). During experimental hypoglycemia, counterregulatory hormone responses, neuroglycopenic symptoms, and cognitive dysfunction all began at lower plasma glucose concentrations in unaware patients (P < 0.01, 0.03, and 0.01, respectively). Moreover, although the magnitudes of their plasma catecholamine responses and autonomic symptoms were reduced (both, P < 0.01), the plasma catecholamine levels at which autonomic symptoms began was not altered. Finally, as seen from glucose infusion rates necessary to maintain identical plasma glucose levels, patients with hypoglycemia unawareness had increased sensitivity to insulin (P < 0.001). CONCLUSIONS - Our results confirm an association between hypoglycemia unawareness and duration of diabetes, glycemic control, and occurrence of severe hypoglycemia, and in addition provide evidence that both autonomic and neuroglycopenic symptoms are affected and that insulin sensitivity is increased, but β-adrenergic sensitivity is not diminished.
UR - http://www.scopus.com/inward/record.url?scp=0028151565&partnerID=8YFLogxK
U2 - 10.2337/diacare.17.12.1397
DO - 10.2337/diacare.17.12.1397
M3 - Article
C2 - 7882808
AN - SCOPUS:0028151565
SN - 0149-5992
VL - 17
SP - 1397
EP - 1403
JO - Diabetes care
JF - Diabetes care
IS - 12
ER -