In a study involving more than 1 million patients, researchers found women with myocardial infarction were more likely to present without chest pain and had higher mortality compared with men. These differences, however, became less pronounced with increasing age.

Researchers collected and analyzed hospital data from the National Registry of Myocardial Infarction on 1,143,513 patients (42.1% women) admitted with confirmed MI from 1994 to 2006. The presence or absence of chest pain/discomfort was the only symptom recorded. Main outcome measures included predictors of MI without chest pain and the relationship between age, sex and hospital mortality.

Researchers found a significant interaction between sex and age with chest pain at presentation (P<.001). The proportion of women who presented without chest pain (42%; 95% CI, 41.8-42.1) was higher when compared with men (30.7%; 95% CI, 30.6-30.8). This difference was larger in younger patients; however, the difference decreased with advancing age. For lack of chest pain in women, multivariable adjusted age-specific ORs were: 1.30 (95% CI, 1.23-1.36) for age younger than 45 years; 1.26 (95% CI, 1.22-1.30), 45 to 54 years; 1.24 (95% CI, 1.21-1.27), 55 to 64 years; 1.13 (95% CI, 1.11-1.15), 65 to 74 years; and 1.03 (95% CI, 1.02-1.04), 75 years or older.

The interaction between sex, age and presentation without chest pain was also significant for mortality, with 14.6% of women and 10.3% of men experiencing in-hospital mortality. According to study results, among MI patients presenting without chest pain, younger women had greater hospital mortality vs. younger men. However, adjusted ORs showed these sex differences decreased or even reversed with advancing age: 1.18 (95% CI, 1.00-1.39) for age younger than 45 years; 1.13 (95% CI, 1.02-1.26), 45 to 54 years; 1.02 (95% CI, 0.96-1.09), 55 to 64 years; (95% CI, 0.88-0.95), 65 to 74 years; and 0.81 (95% CI, 0.79-0.83), 75 years or older.

The researchers said to enhance the current understanding of underlying pathophysiology and potentially sex-tailored health messages to the general public, further research is warranted.

“Our results of sex-based differences in MI symptom presentation in younger patients are provocative and should be confirmed by others with clinical databases of MI or acute coronary syndromes,” the researchers said. “From a public health perspective, it is appropriate to target high-risk groups for delay with information on the American Heart Association/NIH MI message, but until additional research is conducted, the current chest pain/discomfort MI symptom message, which targets women and men equally irrespective of age, should remain unchanged.”

Disclosure: Mr. Frederick reports being an employee of ICON Clinical Research. Dr. Peterson reported receiving research grants from Bristol-Myers Squibb, Eli Lilly, Johnson & Johnson, Sanofi-Aventis, Schering Plough/Merck and St Jude Inc., and consultant fees from Bayer and Pfizer. Dr. Wenger reported receiving research grants and/or trial committee or data and safety monitoring board compensation from Abbott, Eli Lilly, Gilead Sciences, Merck, NHLBT and Pfizer; she also reported receiving consultant fees from Abbott Women’s Advisory Board, AstraZeneca, Gilead Sciences, Merck and Pfizer.

Source: Endocrine Today