Melatonin ineffective in neuronal ceroid lipofuscinosis patients with fragmented or normal motor activity rhythms recorded by wrist actigraphy

Melatonin was tested as a sleeping pill in five patients with neuronal cero id lipofuscinoses. The single-blind, placebo-controlled study consisted of motor activity recordings, sleep logs, and administration of placebo or mel atonin (2.5 or 5 mg). Daily motor activity rhythms were measured by wrist a ctigraphy during four 7-day.periods (baseline, placebo, melatonin 2.5 mg, a nd melatonin 5 mg). The placebo or melatonin was administered in the evenin gs for 3 weeks, and the recordings were made during the last week of the 3- week treatment. Sleep logs were kept by the caregivers during the recording s. Based on period analyses, the activity recordings were evaluated to disp lay a normal (24-h) or fragmented rhythm. Three patients had normal motor a ctivity patterns during the baseline recordings, and administration of plac ebo or melatonin did not affect their rest/activity rhythms. Two patients h ad abnormally fragmented activity rhythms during the baseline periods, and administration of placebo or melatonin did not induce synchronization. Acco rding to the actigraphic data, there were no changes in activity rhythms re sulting from administration of melatonin. However, based on the observation s, three families reported that melatonin slightly improved the sleep quali ty of the patients. These controversial findings show the difficulties invo lved in specifying the role of melatonin in modulating sleep. Thus, we conc lude that more evidence is required before the significance of melatonin as a sleeping pill is defined. (C) 1999 Academic Press.