Heightened Risk of Myocardial Ischemia with Mental Stress Among Black Women Survivors of a Myocardial Infarction in Midlife.

Background: Stark disparities in the outcome of myocardial infarction (MI) persist, with large unexplained variations affecting younger Black women. Mental stress induced myocardial ischemia (MSIMI) is an emerging mechanistic pathway that may help explain excess risks in this group. Objectives: To determine whether MSIMI is more common in Black women with recent premature MI than other demographic groups. Methods: We studied 602 individuals ≤ 61 years of age who were hospitalized for MI in the previous 8 months. Participants underwent 99mTc-sestamibi myocardial perfusion imaging at rest and after mental stress (speech task). A summed difference score (SDS) was used to quantify ischemia. Clinically significant MSIMI was defined as an SDS ≥3. Log-binomial regression models adjusted for sociodemographic, lifestyle, clinical and psychosocial factors. Results: The mean age was 51 years (range, 25-61), 46% were women and 59% self-identified as Black. Black women had a more adverse psychosocial profile and higher rates of obesity and diabetes, but a less severe index MI. The incidence of MSIMI was approximately doubled in Black women than the other groups (p<.001 for interaction). Clinical and psychosocial risk factors did not explain these differences. In a fully adjusted model, the risk ratio of MSIMI for Black women was 2.2 (95% CI, 2.0-2.5) compared to Black men, 2.3 (1.8-2.9) compared to non-Black women, and 1.8 (1.4-2.2) compared to non-Black men. Conclusions: Among midlife individuals with a recent MI, Black women have a disproportionately higher risk of MSIMI. Targeted interventions for this high-risk group are needed. CLINICAL PERSPECTIVE: GRAPHICAL ABSTRACT: