The results show that the duration of MDD (p = 0.004), blood pressure parameters including SBP (p = 0.049), DBP (p = 0.009) and MAP (p = 0.024), IL-6 level (p = 0.019), left PWV (p = 0.004), average PWV (p = 0.026) and FRS (p = 0.002) were significantly higher in medicated patients who remained moderately to severely depressed than those who were non-depressed or mildly depressed. This evidence concerns the gene IL6 and major depressive disorder.