Melatonin for Circadian Sleep Disorders in the Blind
Status:
Terminated
Trial end date:
2012-06-01
Target enrollment:
Participant gender:
Summary
This research project consists of a three part study with five embedded sub studies. The
first study phase identifies "body rhythms" of sleepiness/wakefulness and of melatonin levels
for each subject (including sub-study 1). The second study phase identifies the optimum dose
and timing of melatonin for regulating each individual's 24-hour sleep/waking cycle
(including sub-study 2). The third study phase introduces a new independent variable, light
(including sub-studies 3 and 4). Sub-study 5 is an optional longitudinal study.
Sub-study 1 looks at how keeping a regular sleep schedule affects the body's natural rhythm.
Sub-study 2 looks at how individuals metabolize melatonin. Sub-study 3 tests how individuals'
endogenous melatonin production responds to bright outdoor light and Sub-study 4 tests a
previous finding that artificial bright light exposed daily behind the knee can regulate the
body clock. Sub-study 5 is an optional longitudinal study, an extension of the first study
stage, for subjects whose rhythms are not clearly free-running.