Abstracts

DIURNAL ACTH AND CORTISOL SECRETION IN PATIENTS WITH COMPLEX PARTIAL SEIZURES: CORRELATION WITH NOCTURNAL SEIZURE ACTIVITY

Abstract number : 2.148
Submission category :
Year : 2003
Submission ID : 4062
Source : www.aesnet.org
Presentation date : 12/6/2003 12:00:00 AM
Published date : Dec 1, 2003, 06:00 AM

Authors :
Ingela Danielsson, Eilis Boudreau, William Theodore, Michael A. Rogawski Epilepsy Research Section, NINDS, National Institutes of Health, Bethesda, MD; Clinical Epilepsy Section, NINDS, National Institutes of Health, Bethesda, MD

The secretory activity of the hypothalamo-pituitary-adrenal system fluctuates in a characteristic way during normal nocturnal sleep in humans. Pituitary release of adrenocorticotropin (ACTH) and adrenocortical release of cortisol decreases to a minimum during early sleep when slow wave sleep predominates. ACTH and cortisol release reaches a maximum during late sleep, a time dominated by rapid eye movement (REM) sleep. The role of these hormonal fluctuations in influencing seizure susceptibility during sleep is unknown. As a first step toward assessing whether these hormones could trigger seizures, we sought (1) to determine if persons with complex partial seizures exhibit normal diurnal cycling in ACTH and cortisol secretion, and (2) whether any fluctuations in ACTH and cortisol that occur in these subjects are correlated with nocturnal seizure activity.
Six patients with complex partial seizures, three men and three women, were admitted to the sleep laboratory. The subjects were fitted for 18-channel EEG recording and an indwelling catheter was inserted in an antecubital vein at 10 PM. They were then allowed to adapt to the laboratory overnight. At 8 AM the following morning, the first blood sample was drawn; subsequent samples were collected every 15 min thereafter for 48 h. ACTH and cortisol were determined using an automated analyzer. EEG activity was recorded for the duration of the stay in the sleep laboratory. The patients were maintained on their usual antiepileptic drugs.
Diurnal fluctuations of ACTH and cortisol followed the normal pattern for all six patients. Two of the patients experienced seizures during their hospital stay. One had two complex partial seizures; the other had three complex partial and two simple partial seizures. Analysis of the ACTH plasma levels showed that ACTH levels were at a nadir immediately before the patients experienced either a complex partial or simple partial seizure. Fluctuations in cortisol levels were more varied, and were low in three, falling in three and rising in one event.
Persons with epilepsy exhibit normal circadian fluctuations of ACTH and cortisol. Enhanced seizure susceptibility may be correlated with low ACTH levels. There was no evidence of an association with cortisol.
[Supported by: National Institute of Neurological Disorders and Stroke, NIH.]