Hypoglycemia counterregulation during sleep.
OBJECTIVE
In insulin-treated patients with diabetes, episodes of severe hypoglycemia often occur during sleep, which might reflect an altered counterregulation and reduced awareness. This study examined the influence of sleep on the counterregulatory response to hypoglycemia in healthy subjects.


METHODS
Subjects participated in two experimental conditions; statistical tests relied on within subject comparisons.


METHODS
University hospital sleep laboratory.


METHODS
15 healthy young men.


METHODS
Hypoglycemia (2.8 mmol/l) was induced for 45 min by insulin infusion once during sleep and once at the same time of night while being awake.


RESULTS
Counterregulatory hormone concentrations (epinephrine, norepinephrine, ACTH and cortisol) and sleep recordings were obtained. Differences in the hormonal responses to hypoglycemia between sleep and wake conditions remained non-significant, indicating that sleep does not exert a primary influence on the strength of counterregulation. However, the glycemic threshold for the onset of counterregulation was significantly changed during sleep: The average onset threshold for epinephrine and norepinephrine counterregulation was 3.3 +/- 0.1 mmol/l for the wake condition and 2.7 +/- 0.1 mmol/l for the sleep condition (P < 0.001). A decrease in sleep depth coincided with the onset of the counterregulatory response, with most subjects showing signs of awakening.


CONCLUSIONS
During sleep, the organism is less sensitive to hypoglycemia. Hypoglycemia per se has an awakening effect.
Gais
Steffen
S
Departments of Neuroendocrinology, Medical University of Lübeck, 23538 Lübeck, Germany. gais@kfg.mu-luebeck.de
Born
Jan
J
Peters
Achim
A
Schultes
Bernd
B
Heindl
Britta
B
Fehm
Horst L
HL
Werner
Kern
K
D000293:Adolescent; D000324:Adrenocorticotropic Hormone / Q000097:blood / Q000378:metabolism*; D000328:Adult; D001786:Blood Glucose / Q000378:metabolism; D004837:Epinephrine / Q000097:blood / Q000378:metabolism*; D006801:Humans; D006854:Hydrocortisone / Q000097:blood / Q000378:metabolism*; D007003:Hypoglycemia / Q000139:chemically induced / Q000378:metabolism*; D007328:Insulin / Q000009:adverse effects; D008297:Male; D009638:Norepinephrine / Q000097:blood / Q000378:metabolism*; D012890:Sleep / Q000502:physiology*; D014851:Wakefulness / Q000502:physiology
D001786:Blood Glucose; D007328:Insulin; D000324:Adrenocorticotropic Hormone; D006854:Hydrocortisone; D009638:Norepinephrine; D004837:Epinephrine