Decreased red blood cell membrane deformability in smokers and non-smokers with atherosclerosis

This study determined whether the extent of atherosclerotic plaque buildup, smoking history, or serum cholesterol level could be correlated with red cell membrane deform ability as detetmined by the micropipette aspiration technique. Smoking and non-smoking subjects 40 to 70 years old were grouped by atherosclerotic plaque thickness. A 50% increase (p≤ 0.01) in red cell membrane shear elastic modulus was seen in the advanced atherosclerosis group (plaque thicknes = 2.0 - 4.0 mm). This increase was independent of the smoking history of thesubjects. An increase in shear elastic modulus indicates a decrease in red bloodcell membrane deform ability. Other variables tested including age and serum cholesterol level were not significantly con'elated with red blood cell shear elastmodulus. Such changes in red cell deformability may play an important role in thepathophysiology of vascular occlusion and cerebral ischemia in patients with carotid artery atherosclerosis.