Continuum, Neuroendocrinology, April 2009, Volume 15, Issue 2

Reproductive dysfunction is unusually common among women and men who have epilepsy. It is generally associated with reproductive endocrine disorders that may be causally related. Both epilepsy and antiepileptic drug (AED) use have been implicated in the pathophysiology. Epilepsy effects may vary with the laterality and focality of epileptiform discharges. AED effects vary in relation to their particular properties, especially the presence or absence of enzyme induction. Reproductive steroids have neuroactive properties that can impact seizure occurrence and may provide another modality of treatment. Perhaps one-third of women with epilepsy show notable levels of catamenial exacerbation characterized by one or more of three identified patterns. Women with hormonally sensitive seizures may respond to hormonal treatment with cyclic progesterone supplement or with abolition of their menstrual cycles using parenteral depomedroxyprogesterone or gonadotrophin-releasing hormone analogue treatments. Hypogonadal men may respond to testosterone supplement with or without aromatase inhibitor with clinically important improvement in sexual function, mood, and, perhaps, seizure control.Changes in thyroid function tests are common in men and women with epilepsy, especially in association with enzyme-inducing AED use, but clinically significant thyroid disorders are rarely found to be the consequence of AED use. Epilepsy is associated with disruption of the normal diurnal rhythm and orderly pulsatile secretion in the hypothalamic-pituitary-adrenal axis. Cortisol levels are elevated transiently postictally and to a lesser amount interictally. Elevation of excitatory neuroactive adrenal steroids may contribute to stress-related seizures.(C) 2009 American Academy of Neurology

The relationship between endocrine organs and stroke is most apparent for the sex hormones. Stroke is the third leading cause of death in adulthood and coincides with a time of hormonal transition, particularly for women. Although estrogen has numerous beneficial effects on the vasculature, these are offset by a procoagulant effect. The risk of venous thrombosis and stroke is increased with pregnancy, the puerperium, and estrogen administration. Clinical trials of menopausal estrogen therapy have not been shown to reduce vascular events in primary or secondary prevention trials, and national guidelines advise against their use for this purpose. Testosterone has beneficial effects on lipid profiles, insulin resistance, and obesity that could be beneficial, but no clinical trials data of andropausal testosterone therapy are available. Stroke also occurs as a complication of excessive hormone use, such as ovarian stimulation with infertility and anabolic steroid abuse.(C) 2009 American Academy of Neurology

Mutual interactions between neurohormones and sleep have been extensively studied since the pioneering work done in the 1960s on growth hormone secretion. Hormonal secretion pattern is either influenced predominantly by sleep, independently of circadian timing, or more closely coupled to the light-dark cycle, although both processes ultimately interact with one another. Individual differences regarding gender and age are sometimes prominent, so careful selection of groups to be studied is important. Because of such fragmented data, generalizations can seldom be derived from the available literature. Much like puzzle pieces, every bit of information constitutes but one small component of the broader, more global, neurohormonal picture seen in sleep. We have divided this analysis into discussions of the adenohypophysis, neurohypophysis, and pineal gland, describing the reciprocal influence regarding sleep and the different neurohormones. Specific issues related to gender differences and selected endocrinologic diseases will also be addressed, as well as changes related to the most common sleep disorder, obstructive sleep apnea.(C) 2009 American Academy of Neurology

A compelling body of evidence suggests that hormones derived from the gonads, adrenals, pituitary, and other organs may profoundly affect multiple sclerosis (MS) susceptibility and severity. These hormones have powerful actions on elements of the immune system and also directly affect CNS recovery and resistance to injury. In addition, secretion of adrenal, gonadal, and pituitary hormones may be perturbed in MS with potentially important systemic consequences.(C) 2009 American Academy of Neurology