Age-Specific Sex-Based Differences in Anemia in Patients with Myocardial Infarction

Background: Data are lacking concerning possible age-specific sex-based differences in anemia in myocardial infarction (MI) patients and its association with the outcome. The aim was to assess whether these differences in anemia (on admission and at discharge) in MI patients who underwent percutaneous coronary intervention (PCI) are associated with the outcome. Methods: Data from 5579 MI patients (31.0% women) undergoing PCI at our institution were analyzed. Men and women in different age groups were compared regarding anemia and its association with the 30-day and long-term all-cause mortality. Data were analyzed using descriptive statistics. Results: Women suffered anemia more than men (37.5% vs. 26.8%; p < 0.0001). The prevalence of anemia increased rapidly with age in men but not in women. A J-shaped relationship between age and anemia was found in women. The lower the age, the greater the difference in the prevalence of anemia between the sexes. The difference in the prevalence of anemia at discharge was even more pronounced. Anemia on admission (odds ratio [OR] = 1.39; 95% confidence interval [CI] = 1.10-1.76; p = 0.005) and at discharge (OR = 2.61; 95% CI = 1.98-3.44; p < 0.0001) predicted a higher 30-day mortality. Women had a better adjusted long-term prognosis (hazard ratio [HR] = 0.78; 95% CI = 0.69-0.87; p < 0.0001) for the total population. Anemia on admission (HR = 1.43; 95% CI = 1.29-1.60; p < 0.0001) and at discharge (HR = 1.96; 95% CI = 1.23-2.21; p < 0.0001) predicted a higher long-term mortality. Conclusion: Younger women with MI suffer anemia more frequently than their male peers. Anemia was associated with a worse outcome. Age-specific sex-based differences in anemia help to explain the increased sex-related mortality in MI patients undergoing PCI.