Background: Discrimination, a form of chronic psychological stress, is related to certain chronic health conditions such as poor physical health and hypertension. However, little is known about the associations of everyday discrimination with risk of myocardial infarction.
Methods and Results: We assessed the association between everyday discrimination (discrimination) and myocardial infarction (MI) using a prospective, nested case control study of 548 women (267 cases, 281 controls), selected from 26,763 women without a history of cardiovascular disease at baseline who participated in the Women’s Heath Study (WHS). Among 267 MI cases, there was a mean follow-up of 8.8 + 4.1 years from date of WHS randomization to date of MI event. At baseline, the mean age of participants was 53.6 + 6.1 years. Cases and controls were matched for age and smoking history. Discrimination was assessed by 5 questions where women reported whether they were: 1) treated with less courtesy/respect than others; 2) treated as not being smart; 3) treated as if others were afraid of them; 4) received poorer service at restaurants/stores; or 5) felt threatened/harassed. Responses were based on a Likert scale of 1=never to 5=at least once/weekly with higher scores indicating more experiences with discrimination. In unadjusted logistic regression models of increasing tertiles of discrimination, we found no significant association between discrimination and odds of MI [Odds Ratios (OR) and 95% confidence intervals (95%CI): 1.00, 1.28 (0.85-1.94), 1.06 (0.69-1.64); ptrend=0.5]. Adjustment for cardiovascular disease risk factors (lipid parameters, hsCRP, family history of MI, hypertension, body mass index, diabetes, and alcohol consumption) revealed an inverse-U-shaped relationship [OR, 95%CI: 1.00, 2.14 (1.21-3.77), 1.55 (0.87-2.78); ptrend= 0.03], suggesting that these factors obscured the association in unadjusted models. Notably, addition of education and income to the crude model alone [1.00, 1.38 (0.89, 2.15), 0.97 (0.61, 1.54) ptrend= 0.2] or to the model with the cardiovascular risk factors [1.00, 2.27 (1.25-4.10), 1.36 (0.73, 2.53); ptrend= 0.02] had minimal impact on odds of MI in these women.
Conclusion: Among women participating in the WHS follow-up cohort, higher levels of everyday discrimination were related to increased odds of myocardial infarction in an inverse-U-shaped manner, a finding that is obscured by traditional cardiovascular disease risk factors. Access to measures associated with a healthy heart might be important to myocardial infarction risk attenuation among women reporting everyday discrimination. Further research is warranted to elucidate the relationship between everyday discrimination and increased risk of MI.