Abstract 576: Gender Differences in Carotid Artery Plaque Composition Do Not Exist in Response to Lipid Lowering Therapy at Two Years Among Men and Women with Carotid or Coronary Artery Disease and Elevated ApoB Levels
Introduction: Recent, age-adjusted stroke death rates declined greater in men than women. Whether this is related to gender differences in the atherosclerotic plaque response to therapy is not known. Postmortem coronary artery histopathology and post-surgical carotid endarterectomy studies demonstrate that women have less calcification and inflammatory cells, but more smooth muscle cells than men.
Hypothesis: We hypothesized that gender differences exist in carotid plaque composition (CPC) in response to lipid lowering therapy (LLT) comparing living men and women.
Methods: The CPC study is a prospective, randomized study evaluating the effect of LLT: 1) atorvastatin + placebo + placebo vs 2) atorvastatin + niacin ER + placebo 3) atorvastatin + niacin ER + colsevelam on CPC. Participants had coronary or carotid artery disease and ApoB levels ≥120 mg/dL. CPC was evaluated using MRI. The change over two years in % wall volume (PWV) [(wall volume/total vessel volume) х 100%], a measure of plaque burden that adjusts for variation in artery size, and % lipid rich necrotic core (LRNC) volume among slices with LRNC present were evaluated. Statistical analysis used Wilcoxon rank sum test, chi-square, and multivariate linear regression.
Results: There were 40 women and 73 men in the study with both baseline and 2 year MRI scans. Women vs. men were older, mean±SD age 58±9 vs. 54±8 yrs. (p=0.009), had higher HDL-C, 49±14 vs. 40±11 mg/dL (p=0.002), and higher ApoA1 145±26 vs. 126±20 mg/dL (p<0.001). ApoB levels were not significantly different, 127±31 vs. 121±25 mg/dL (p=0.2). Adjusted for age, HDL-C (strongly correlated with ApoA1, r=0.89), ApoE, prevalence of MI and metabolic syndrome (statistically significant in the full baseline cohort), there were no statistically significant gender differences at 2 years with LLT in change in PWV, [[Unable to Display Character: ∆]] -0.1 (95% CI: -0.7, 0.6%) (p=0.8) or %LRNC among participants with LRNC, [[Unable to Display Character: ∆]] 0.5 (95% CI: -2.5, 3.5%) (p=0.7).
Conclusions: We did not detect statistically significant gender differences in change in PWV and %LRNC in response to LLT. Although the results are consistent with no gender differences they remain inconclusive due to the small sample size. Further gender studies in the biology and treatment of arterial atherosclerosis are needed.
Author Disclosures: P. Paramsothy: None. J. Hong: None. D. Isquith: None. E. Hulphers: None. H. Bai: None. P. Shadzi: None. M. Neradilek: None. E.A. Gill: None. X. Zhao: None.
- © 2015 by American Heart Association, Inc.