Abnormal 24-hour urinary excretory pattern of 6-sulphatoxymelatonin in both phases of cluster headache

The typical cyclic occurrence of cluster headache suggests the involvement of hypothalamic rhythm regulating centers in the pathogenesis of this prima ry headache. In previous studies, reduced 24-h plasma melatonin levels duri ng the cluster period, loss of circadian melatonin secretion in remission, as well as permanently reduced excretion of urinary melatonin in both illne ss phases have been reported, supporting the hypothesis of a hypothalamic d erangement. In this study, the 24-h urinary excretion of the main melatonin metabolite, 6-sulphatoxymelatonin, was evaluated in 20 cluster period clus ter headache patients. Thirteen were retested 12 months later, in the same period of the year, during remission. Fourteen age- and sex-matched healthy subjects were the controls. As expected, significantly higher levels of 6- sulphatoxymelatonin were present in nocturnal urine than in day-time urine in controls, while in both cluster headache groups urinary levels of this m etabolite did not differ between day and night. Nocturnal levels of 6-sulph atoxymelatonin were significantly lower in both cluster headache groups tha n controls. Day-time levels did not differ significantly between the groups . Altered excretion of urinary 6-sulphatoxymelatonin even during remission indicates that at least some of these anomalies are independent of the pain , and provides further evidence of involvement of the hypothalamic rhythm r egulating centers in cluster headache.