Low Levels of Low-Density Lipoprotein Cholesterol and Blood Pressure and Progression of Coronary Atherosclerosis

Objectives We investigated coronary atheroma progression in patients with low levels of low-density lipoprotein cholesterol (LDL-C) and systolic blood pressure (SBP). Background Low LDL-C and SBP beneficially impact coronary atherosclerosis. However, the association between intensive control of both risk factors and coronary plaque progression remains unclear. Methods Changes in atheroma burden monitored by intravascular ultrasound were studied in 3,437 patients with coronary artery disease (CAD) who were stratified according to on-treatment LDL-C and SBP. Results Patients with very low LDL-C (<= 70 mg/dl) and normal SBP (<= 120 mm Hg) had less progression in percent atheroma volume (PAV) (p < 0.001) and total atheroma volume (TAV) (p < 0.001), more frequent plaque regression (p = 0.01), and less frequent plaque progression (p < 0.001). In patients with SBP <= 120 mm Hg, very low LDL-C was associated with less progression of PAV (+ 0.30%, 95% confidence interval [CI]:-0.17% to 0.77% vs. + 0.61%, 95% CI: 0.17% to 1.05%, p = 0.01) and TAV (-3.9 mm(3), 95% CI:-7.24 to-0.63 mm(3) vs.-1.2 mm(3), 95% CI:-4.31 to 1.92 mm(3), p < 0.001). In patients with LDL-C <= 70 mg/dl, normal SBP was not associated with less progression of PAV (+ 0.51%, 95% CI: 0.04% to 0.99% vs. + 0.61%, 95% CI: 0.17% to 1.05%, p = 0.159) or TAV (-2.3 mm(3), 95% CI:-5.59 to 1.05 mm(3) vs.-1.2 mm(3), 95% CI:-4.31 to 1.92 mm3, p = 0.617). Conclusions Very low LDL-C and normal SBP are associated with the slowest progression of coronary atherosclerosis. Although a greater beneficial association is observed in patients with very low LDL-C, these findings suggest the need for intensive control of global risk in patients with CAD. (J Am Coll Cardiol 2009; 53: 1110-5) (C) 2009 by the American College of Cardiology Foundation