Narcolepsy with cataplexy is caused by a deficiency in the production of hypocretin/orexin, which regulates sleep and wakefulness, and also influences appetite, neuroendocrine functions and metabolism. In this case-control study, 11 patients with narcolepsy with cataplexy and 11 healthy adults underwent an oral glucose tolerance test, and dexamethasone suppression/corticotropin-releasing hormone stimulation test. The average age of patients and controls was 35.1 ± 13.2 and 41.0 ± 2.9 years, respectively, body mass index was 28.1 ± 6.6 and 25.5 ± 4.7 kg m(-2) . We did not find evidence of a significantly increased prevalence of disturbed glucose tolerance in patients with narcolepsy. After hypothalamo-pituitary-adrenal axis suppression, the number of non-suppressors did not differ between the groups, indicating normal negative feedback sensitivity. The level of cortisol after dexamethasone suppression was significantly lower in patients with narcolepsy, suggesting a slight basal downregulation and/or a slightly increased negative feedback sensitivity of the major endocrine stress system in narcolepsy. Following corticotropin-releasing hormone stimulation, there were no significant differences in levels of adrenocorticotropic hormone or cortisol, and in adrenocortical responsivity to adrenocorticotropic hormone. Finally, patients with narcolepsy displayed significantly higher plasma levels of tumour necrosis factor alpha, soluble tumour necrosis factor receptor p55, soluble tumour necrosis factor receptor p75 and interleukin 6 after adjustment for body mass index. The present study confirms that narcolepsy by itself is not associated with disturbances of glucose metabolism, but goes along with a subtle dysregulation of inflammatory cytokine production. We also found that dynamic hypothalamo-pituitary-adrenal system response is not altered, whereas negative feedback to dexamethasone might be slightly enhanced.
- MeSH
- Adrenocorticotropic Hormone blood MeSH
- Dexamethasone pharmacology MeSH
- Adult MeSH
- Glucose Tolerance Test MeSH
- Corticotropin-Releasing Hormone pharmacology MeSH
- Hydrocortisone blood MeSH
- Body Mass Index MeSH
- Interleukin-6 metabolism MeSH
- Cataplexy blood complications metabolism MeSH
- Blood Glucose metabolism MeSH
- Humans MeSH
- Narcolepsy blood complications metabolism MeSH
- Case-Control Studies MeSH
- Pituitary-Adrenal System drug effects metabolism MeSH
- Hypothalamo-Hypophyseal System drug effects metabolism MeSH
- Tumor Necrosis Factor-alpha blood MeSH
- Check Tag
- Adult MeSH
- Humans MeSH
- Male MeSH
- Female MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
Narcolepsy is characterized, beside other features, by excessive daytime sleepiness and disturbed sleep at night. The pineal hormone melatonin may affect the sleep characteristics. The aim of the study was to compare the circadian rhythm in salivary melatonin in narcoleptic patients with that in control healthy subjects; 18 patients and 21 age- and gender-matched controls were involved. Narcoleptic patients exhibited a nocturnal increase in salivary melatonin similar to the one in control subjects. The morning melatonin decline in the narcoleptic group, as opposed to the control group was, however, not significant, as 8 out of 18 patients exhibited elevated melatonin levels also during the day. In these patients, the mean daytime value of the multiple sleep latency test (MSLT) was decreased when compared with that in patients with undetectable daytime melatonin levels. The results suggest that in some narcoleptic patients the circadian rhythm might be disturbed.
- MeSH
- Biomarkers metabolism MeSH
- Chronobiology Disorders etiology metabolism MeSH
- Circadian Rhythm physiology MeSH
- Child MeSH
- Adult MeSH
- Financing, Organized MeSH
- Middle Aged MeSH
- Humans MeSH
- Melatonin metabolism MeSH
- Narcolepsy complications metabolism MeSH
- Saliva metabolism MeSH
- Check Tag
- Child MeSH
- Adult MeSH
- Middle Aged MeSH
- Humans MeSH
- Male MeSH
- Female MeSH
