2.6. Statistical Analyses
REGRESSIONS
The sample size of 48 patients, with 24 subjects per treatment arm, was determined to yield a power of 80% with a 5% significance level to detect a 30% difference in Sirt1 serum concentrations. Participants were randomly assigned in a 1:1 ratio using computer-generated numbers to include participants in the resveratrol or energy restriction groups.Pre- and post-intervention variables were described as the median and interquartile range (IQR). Wilcoxon’s test was used for pre- and post-treatment analysis. Mann-Whitney’s U test was used for intergroup comparisons of baseline variables and changes. Partial correlations controlled by intervention group (resveratrol and energy restriction) and sex (men and women) were used to evaluate the relationship between changes (Δ) of SIRT1 and vascular reactivity. Multiple linear regressions with a backward method were used to assess this association further, using changes (Δ) of triglycerides, BMI, total cholesterol, and noradrenaline as adjustment variables and changes (Δ) of FMD and NMD as dependent variables. Predictive variables with weak association (The level of significance was set at 