Abstract 16048: Young Women Post-MI Have Higher Levels of Inflammation Before and After Stress Testing
Objectives: Young women have poorer prognosis after myocardial infarction (MI) compared with similarly aged men. Inflammatory responses to mental and physical stress may help explain these sex differences.
Methods: We examined 98 patients (49 women and 49 men) age 18-59 years with recent MI (past 6 months). Women and men were matched for age, type of MI, and time since MI. Interleukin 6 (IL-6) levels were measured at baseline, after mental stress using a speech task, and after exercise/pharmacologic stress (60 and 90 min). Depressive symptoms were measured with the Beck Depression Inventory (BDI) and angiographic coronary artery disease (CAD) severity was quantified with the Gensini score. Analysis was stratified by the median age of 50. Geometric mean levels of IL-6 were obtained from general linear regression models.
Results: In both age groups, women had less angiographic CAD and a similar level of conventional risk factors compared with men. Despite this, baseline IL-6 geometric means before both mental and physical stress were twice as high in women ≤50 years of age compared to age-matched men (3.5 vs. 1.8 pg/mL, p=0.002, across both conditions), while they were similar in women and men age >50 years (2.3 vs. 2.2 pg/mL, p=0.83). After mental stress, IL-6 levels increased in both women and men in a similar fashion and remained higher in women ≤ 50 years than men at both 60 min (5.6 vs. 2.6 pg/mL, p<0.001) and 90 min (6.2 vs. 3.3 pg/mL, p=0.01). No significant difference was found between women and men >50 years of age at any time point after mental stress (sex by age interaction across all three time points: p=0.02). Results were similar for physical stress. After accounting for demographic characteristics, cardiovascular risk factors, CAD severity, and BDI score, the sex by age interaction across all three time points remained significant for mental (p=0.02) and physical stress (p=0.02).
Conclusions: After MI, young women age 50 years or younger, compared with age-matched men, have remarkably higher levels of inflammation at baseline and after both mental and physical stress, with a similar inflammatory response to both stressors. Sustained levels of inflammation in young women, not their response to stress, may contribute to their adverse outcomes post-MI.
- © 2013 by American Heart Association, Inc.