Melatonin for sleep disorders in visually impaired children

Melatonin is widely used for management of sleep disorders in children with poor or no vision. The current review planned to examine studies on the use of melatonin in these children to determine whether this drug is effective for improving their sleep (safety is not mentioned in objectives or abstract and adverse effects is a secondary outcome). We only wanted to use studies where the children had been randomly allocated to a treatment group and a control group that got no treatment or another medication or a placebo. We did not find any of these studies that were suitable to be included in our review and so we are unable to draw any conclusions about whether or not melatonin improves sleep for visually impaired children. To find out, we need appropriately designed clinical trials. Due to lack of knowledge about best practice in the use of melatonin with these children, it would be useful to have researchers involved who are experienced in sleep disorders and in evidence-based practice research. In addition, studies involving more than one location would be beneficial to increase the number of children being evaluated and make it more likely we will reach solid conclusions about whether melatonin works for this group of children, as well as details about the most effective dosage and timing of the treatment.

Authors' conclusions: 

There is currently no high quality data to support or refute the use of melatonin for sleep disorders in visually impaired children. Placebo-controlled trials examining important clinical outcomes such as sleep quality, sleep latency, duration of sleep and night-time awakenings are needed. As the numbers of children meeting study inclusion criteria are likely to be low at individual sites, multicentre collaboration between developmental paediatricians, sleep physicians and other health care professionals is essential to achieve sufficient sample size for controlled studies. Such collaboration would help facilitate local recruitment at multiple sites, with study oversight being provided by paediatricians with expertise in sleep disorders. Participation of collaborators with experience in evidence-based practice research is also desirable due to the lack of protocols on melatonin therapy in the target population.

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Background: 

Exogenous melatonin helps in regulating the circadian rhythm and is widely used for the management of sleep disorders in visually impaired children. 

Objectives: 

The aim of the review was to assess melatonin therapy for treatment of non-respiratory sleep disorders in visually impaired children, with regard to improvement in sleep habit, sleep scheduling and sleep maintenance, when compared with placebo or no treatment.

Search strategy: 

We searched the following databases between February 2011 and July 2011: the Cochrane Central Register of Controlled Trials (CENTRAL) 2011(1) searched on 4th February 2011; MEDLINE (1950 to June Week 3, 2011) searched on 20th June 2011; EMBASE (1980 to June Week 4, 2011) searched on 7th July 2011; CINAHL (1937 to 21 September 2011); the metaRegister of Controlled Trials (this includes ClinicalTrial.gov) searched 20 July 2011, and reference lists of papers identified after initial screening

Selection criteria: 

We planned to include randomized controlled trials (RCTs) and quasi-RCTs, including cross-over studies. Treatment would be exogenous melatonin. Control groups could be placebo, other medication for sleep disorders or no treatment. Outcomes sought were improved sleep with regard to timing and duration, quality of life and adverse events. 

Data collection and analysis: 

Three review authors independently assessed trials for inclusion in the review.

Main results: 

We did not find any studies fulfilling the inclusion criteria, therefore no outcome data are reported.

We identified nine studies after initial screening and, after further evaluation, we excluded these. The excluded studies involved a total of 163 individuals aged two years to 18 years. We excluded studies for three main reasons: they were non-randomized or case series studies, they were studies of people over 18 years of age or even where the study was randomised, the study population was mixed and results pertaining to the visually impaired cohort could not be independently evaluated. No significant adverse effects of melatonin were reported in these excluded studies.