Study Overview To meet the objectives of the project, two groups will be compared, one that will be supplemented with vitamin K and another of patients who will receive corn starch as a placebo. Patients are going to have a follow up during 3 months with periodic evaluations every 30 days.
This is a double-blind study, it is achieved by maintaining similarities in appearance, taste and smell between the treatments that will be delivered in the same vials, with same number of pills and identical in shape, color and consistency for each study group.
Patient recruitment will take place by disseminating information through physical and social media, once potential participants have been identified, they will be contacted and informed about the project, and if they decide to participate in the study, they will be asked to sign the informed consent.
Simple randomization will be performed using R software to assign participants to one of the study groups. A clinical history, anthropometric measurements and blood sampling shall be applied.
Nutritional recommendations based on the position of the Academy of Nutrition and Dietetics for the treatment of overweight and obesity and the healthy eating plate of Harvard University will be given. An appointment is to be scheduled every 30 days in order to provide the supplementation and follow-up. At the end, the pertinent statistical analyzes will be carried out.
Notification of adverse effects will be made in each of the sessions, in addition to this the participants will have the contact of the researchers to notify any anomaly.
Sample's size calculation
The sample size was calculated using the statistical formula for the comparison of two means. This estimate was made using the following formula:
n=2(Zα+Z\[1-β\]2xSD2/d2
Where:
n= sample size required in each group SD= standard deviation of the effect Zα: to the value of Z for a confidence level of 95% Z\[1-β}: to the value of Z for a statistical power of 80% D= effect size A total of 19.72 patients per group were obtained. Considering a 20% loss, 24 patients are needed per study group.
Ethical considerations The study was approved by the Biosafety committee, research ethics committee and research committee of the University Center for Health Sciences, University of Guadalajara: CI-00421. The committees of the University have the authority to monitor and audit the study at any of its stages once it has been approved.
Objetives General objective Evaluate the effect of vitamin K2 supplementation on methylation, the serum concentration of total vitamin K, osteocalcin, growth arrest-specific 6 protein, leptin, inflammatory markers, cardiometabolic risk factors and cardiovascular risk in young Mexican adults with overweight or obesity.
Specific objectives
1. Compare the baseline variables between groups.
2. Compare the variable changes across the time within groups
3. Compare the variable changes across the time between groups
Statistical analysis The Shapiro-Wilk normality test is performed to determine whether the analysis will require parametric or non-parametric tests. Qualitative variables will be expressed as frequencies and percentages, while quantitative variables will be expressed as mean and standard deviation in parametric data or medians and ranges in non-parametric data.
Specific objective 1 Statistical technique T-student for independent samples if it has a normal distribution or by U-Mann Whitney for independent samples if it does not have a normal distribution
Specific objective 2 Variables with two measures Statistical technique T-student for paired samples if it has a normal distribution or the Wilcoxon signed-rank test if it does not have a normal distribution
Variables with more than two measures Statistical technique Repeated measures ANOVA if it has a normal distribution or the Friedman Test if it does not have a normal distribution
Specific objective 3 Statistical technique The effect size of the groups is compared with T-student for independent samples if it has a normal distribution or by U-Mann Whitney for independent samples if it does not have a normal distribution
