Effects of Melatonin on Sleep Quality and Cognitive Function of Shift Workers with Sleep Disorder: A Randomized, Double-Blind, Placebo-Controlled Trial

Determining the effects of melatonin on sleep quality and cognitive performance of resident physicians with sleep disorders following shift work

A controlled, parallel-group, double-blind, randomized, phase 2-3 clinical trial on 70 patients. The rand function of Excel was used for randomization.

The study is conducted in the Psychiatric Research Center of Roozbeh Hospital in an outpatient setting on shift workers with sleep disorder. Seventy patients will be randomly divided into melatonin or placebo groups with blocks of four and will be evaluated in terms of sleep quality, occupational cognitive failures, and side effects at baseline and weeks 1 and 4. Allocated group numbers will be kept in sealed and opaque envelopes to conceal the treatment from patients and the research team, and melatonin and placebo are exactly matched.

Resident physicians with night shift jobs aged 25 to 55 who had at least seven night shifts during the last month, have a plan to spend seven night shifts during the study, complain of sleep disorder after shift, and have poor sleep quality are included in the study. Complaints of sleep disturbance during normal sleep hours, pregnancy/its intention and breastfeeding in female participants, history of sensitivity or occurrence of complications after taking melatonin and its agonists, and And the history of thyroid, cardiovascular, kidney, and endocrine diseases and psychiatric disorders (except sleep disorders) lead to non-inclusion. Additionally, working fewer than six night shifts (i.e., zero to five shifts) during the study month resulted in exclusion.

For the participants of the intervention and control groups, melatonin 5mg and placebo, respectively, are prescribed half an hour before bedtime following the night shift for one month.

Sleep Quality

Permuted block randomization using A and B blocks in a 1:1 ratio will be done with n=4: AABB, ABAB, ABBA, BABA, BAAB, BBAA The blocks were randomly used to achieve total sample size. ("A" and "B" are the study groups).

An independent group will perform randomization, allocation concealment, and blinding procedures. The allocated group numbers will be kept confidential in sequentially numbered, sealed, and opaque envelopes to conceal treatment assignments from patients, healthcare providers, outcome assessors, and the research team. Melatonin and matched placebo are identical in size, shape, color, smell, and taste.