Double blind randomised placebo controlled trial of low dose melatonin for sleep disorders in dementia.
Disturbance of sleep is common in individuals with dementia where there may be reversal of the sleep-wake cycle. People with dementia of the Alzheimer's type have melatonin secretion rhythm disorders. There is some evidence that treatment with exogenous melatonin is an effective treatment for sleep disturbance associated with dementia. A randomised double blind placebo controlled cross over trial was undertaken to test the hypothesis that slow release exogenous melatonin 6 mg improves sleep for people with dementia.
                Forty-four participants with DSM-IV diagnoses of dementia with sleep disturbance were selected for a seven week randomised double blind cross over trial of slow release melatonin 6 mg versus placebo. Sleep parameters were objectively measured using wrist actigraphy.
                Twenty-five out of 44 completed the trial. Sleep was significantly disturbed in the sample population. Melatonin had no effect on median total time asleep (n=25, z=1.35, p=0.18), number of awakenings (n=25, z=0.32, p=0.75) or sleep efficiency (n=25, z=0.17, p=0.24). Nor were there any carry over effects from melatonin.
                Contrary to previous findings, we found no evidence that two weeks of exogenous melatonin is effective in improving sleep in people with dementia, although possible benefits of melatonin following longer periods of administration cannot be discounted.
                Copyright 2002 John Wiley & Sons, Ltd.
This review finds no evidence that cannabinoids are effective in the improvement of disturbed behaviour in dementia or in the treatment of other symptoms of dementia. More randomized double-blind placebo controlled trials are needed to determine whether cannabinoids are clinically effective in the treatment of dementia.