24-HOUR MELATONIN AND CORTISOL PLASMA-LEVELS IN RELATION TO TIMING OFCLUSTER HEADACHE

The cyclic recurrence of cluster periods and the regular timing of hea dache occurrence in duster headache (CH) induced us to study the circa dian secretion of melatonin and cortisol in 12 patients with episodic CH, during a cluster period, and compare them with 7 age- and sex-matc hed healthy controls. Blood was sampled every 2 h for 24 h. All subjec ts were confined to a dark room from 22.00 to 08.00. plasma melatonin levels were significantly reduced in CH patients (repeated measures AN OVA p < 0.03; mesor p < 0.02), and the cortisol mesor was significantl y increased (p < 0.03). Amplitudes and acrophases did not differ betwe en the groups. individual cosinor analysis showed that 4/12 (33.3%) CH patients had no significant meratonin rhythm, and that 5/11 (45.5%) h ad no cortisol rhythm. Group analysis of cosinor revealed significant rhythmicity of melatonin and cortisol secretion in both groups. In con trols, the timing of melatonin and cortisol acrophase significantly co rrelated with each other, indicating that the biorhythm controllers fo r the secretion of these hormones were synchronized. Such correlation was not found in the CH patients; mesor, amplitude and acrophase of me latonin and cortisol did not correlate with duration of illness, durat ion of headache in course, or time since last headache attack.