https://doi.org/10.1007/s00392-024-02526-y
1Deutsches Herzzentrum München Klink für Herzkreislauferkrankungen München, Deutschland; 2Deutsches Herzzentrum München Klinik für Herz- und Kreislauferkrankungen München, Deutschland; 3Deutsches Herzzentrum München München, Deutschland
Background: Gender-related differences in symptoms, treatment, and outcomes in patients presenting with myocardial infarction (MI) are described but vary largely between studies. Most studies describe worse outcomes in female patients mainly due to advanced age, unfavorable risk factor distribution, delayed diagnosis and treatment, leading to higher post-MI mortality rates. Many of today's guideline-relevant studies include less women and do not adjust for gender disparities, leading to inconsistent results, misinterpretation, and less frequent evidence-based therapy of female patients.
Objective: To investigate gender-specific differences in outcomes in patients with myocardial infarction.
Methods: A retrospective analysis was conducted using 1) a clinical cohort of 1,206 patients with acute STEMI treated with primary PCI and 2) a secondary dataset from German health insurance claims, comprising 1.3 million patients with underlying atherosclerotic disease of whom 37,648 suffered a STEMI. Propensity score matching was used to adjust for common risk factors and achieving a 1:1 female-to-male ratio across both cohorts, with each cohort comprising 10,416 individuals. Additionally, major adverse cardiac events (MACE) were evaluated for both cohorts. Within the clinical cohort exclusively, several specific measures were analyzed: the size of the infarction, myocardial salvage assessed through serial single-photon emission computed tomography (SPECT) imaging, left ventricular ejection fraction measurements taken post-myocardial infarction and again after six months, and peak levels of creatine kinase myocardial band (CK-MB) and troponin T.
Results: Before matching, we found a survival advantage for men, with hazard ratios (HR) of 2.00 (95% CI, 1.34-2.98, p<0.001 in the clinical cohort and 1.55 (95% CI, 1.48-1.61, p<0.001) in the insurance data. Following propensity score matching, each group in the clinical cohort retained 234 patients, and 10,416 patients in the insurance data. Post-matching analysis showed a reversed survival advantage, now favoring women, with HRs of 0.95 (95% CI, 0.58-1.56, p=0.84) in the clinical cohort and HRs of 0.91 (95% CI, 0.86-0.96, p<0.001) in the insurance data. Similar effects were shown for MACE. Clinical data showed larger infarct sizes after 14 days for male patients (female: 12.87 vs. male: 15.97, p=0.012), and increased myocardial salvage in female patients (female: 0.58 vs male: 0.45, p=0.0009).
Conclusion: After adjusting for age and comorbidities, our study unveiled superior outcomes in female patients’ post-MI, suggesting female-intrinsic protective factors. In clinical routine, one must consider that female MI-patients are significantly older and present with unfavorable risk distribution, leading to higher mortality rates. Acknowledging most of today's available data, there is an urgent need for additional clinical and experimental research to develop gender-specific treatment options to enable personalized medicine.