CD34 and hypertensive disorder: As the significant positive association between active arterial wall thickening and circulating CD34+ cells was only observed in subjects without hypertension, we tested the effect of differing hypertension status on the association between active arterial wall thickening and circulating CD34+ cells, and found significant differences using all models: p < 0.001 for Model 1, p = 0.009 for Model 2, and p = 0.009 for Model 3 (data not shown).