JMIR Publications

ABSTRACT

Background:

Glycemic variability has been shown to be a determining factor in the development of micro- and macrovascular complications in patients with type 2 diabetes mellitus (T2DM). Melatonin, a hormone that regulates various biological rhythms, including those that affect glucose regulation such as hunger, satiety, sleep, and circadian rhythm of hormone secretion (cortisol, growth hormone, catecholamines, and insulin), has been found to be deficient in individuals with T2DM in several studies. That being said, an important question arises: could replacement of melatonin potentially reduce glycemic variability in these patients? This is an intriguing possibility that warrants further investigation, as it may offer a new avenue for improving glycemic control and reducing the risk of complications associated with T2DM.

Objective:

To evaluate whether replacing melatonin in individuals with T2DM who are deficient in this hormone can have a positive impact on regulating insulin secretion rhythms and improving insulin sensitivity, ultimately leading to a reduction in glycemic variability.

Methods:

Design Crossover, randomized, double-blind, placebo-controlled study. Methods In this clinical trial, patients with T2DM in Group 1 will receive melatonin in the first week, undergo a washout period in the second week, and receive a placebo in the third week (melatonin-washout-placebo). Group 2 will be randomized to receive a sequence of placebo-washout-melatonin. During the last three days of the first and third weeks, capillary blood glucose levels will be measured at six different times, before and after meals. The trial results will be reported in accordance with the CONSORT guidelines for clinical trial reporting.

Results:

Thirty T2DM patients will be randomized into two groups: melatonin-washout-placebo or placebo-washout-melatonin. The study aims to compare the mean differences in blood glucose levels between the two groups during the first and third weeks. Additionally, it is expected that there will be a difference in glycemic variability between the days when patients receive the placebo and those when they receive melatonin. After the initial results, the number of patients will be recalculated. If the number of patients is less than or equal to 30, the study will be terminated. If the number of patients exceeds 30, new patients will be recruited to participate in the study.

Conclusions:

This study may answer whether melatonin is capable of reducing glycemic variability in patients with T2DM. The crossover model is necessary due to the numerous variables involved (including diet, physical activity, sleep parameters, pharmacological treatments) in the circadian variations of glucose. The low cost of melatonin and its possible role in reducing the serious complications of this disease encouraged this work. Clinical Trial: This study is registered in the Brazilian registry of clinical trials (https://ensaiosclinicos.gov.br/) under the number: RBR-6wg54rb