Acute Coronary Syndrome
Role of Sex Difference in Modifiable Risk Factors After Acute Myocardial Infarction
2024 Volume 88 Issue 8 Pages 1223-1224
Details
2024 Volume 88 Issue 8 Pages 1223-1224
Acute myocardial infarction (AMI) remains a leading cause of mortality and morbidity worldwide and continues to be a substantial proportion of the global disease burden.1 Not long ago, AMI was perceived as a male disease, but the subsequent accumulation of evidence regarding the association between women and AMI has increased interest in the impact of sex differences on the incidence, progression, and prognosis of AMI. In general, the risk of developing AMI is lower in women than in men,2 although this trend does not necessarily apply to the clinical outcomes after AMI, realizing the importance of risk management that takes sex difference into account.
Article p 1211
In the Prospective, Urban Rural Epidemiological (PURE) study in which 202,072 individuals aged 35–70 years from urban and rural communities in 27 countries were enrolled, cardiovascular risks were lower by approximately three-quarters in women compared with men, a result that was observed regardless of income level or country.3 On the other hand, an increased risk for cardiovascular disease in women was observed, particularly in high-income countries, where women’s risk of recurrent cardiovascular disease was equal to or greater than that of men.3 The PURE study also reported that treatment of cardiovascular risk factors (primary prevention), such as hypertension, dyslipidemia, and diabetes, was more common in women than men, whereas use of secondary prevention, diagnostic tests, and revascularization procedures was less frequent in women, which may contribute to the increased risk for long-term death after AMI in women.3 A prospective cohort study in the United Kingdom of 471,998 people with no history of cardiovascular disease reported that the incidence of AMI was almost 3-fold higher in men than in women, but several risk factors, such as hypertension, smoking, and diabetes, were more strongly associated with AMI in women than in men,4 highlighting the importance of risk factor management in women. Indeed, the timing of the onset of coronary artery disease (CAD) differs between men and women, and in women, CAD increases after menopause and often develops at an older age, and at the onset of CAD, there is an increased risk overlapping coronary risk factors, such as hypertension and dyslipidemia, often complicated by progressive vascular disease.5 It is also pointed out that women are less likely to present with typical ischemic symptoms compared with men, resulting in delays in diagnosis and treatment and leading to more severe CAD.6
Systematic research on sex differences has been also conducted in Japan. The Japanese Acute Coronary Syndrome Study (JACSS), which incorporated 1,925 Japanese patients with first AMI, first reported a sex difference in the relative importance of each risk factor in the development of AMI in Japan.7 In JACSS, hypertension, smoking, diabetes, and family history were consistent risk factors in both men and women across different geographic regions of Japan, whereas hypercholesterolemia was an independent risk factor for AMI only in men. Another report from JACSS observed that women, compared with men, were significantly older, had worse clinical profiles on admission, had higher rates of in-hospital death, but female sex itself was not independently associated with increased in-hospital death after adjustment for baseline difference.8 A past report from K-ACTIVE (Kanagawa-ACuTe cardIoVascular rEgistry) that included 2,491 patients with ST-segment elevation MI (STEMI) reported that percentages of prehospital 12-lead ECG, reperfusion therapy and achievement of door-to-device time ≤90 min were similar between men and women.9 As a result, in-hospital mortality rates were similar between the sexes, suggesting that guideline-based treatment might have attenuated the sex difference in in-hospital death. The J-MINUET (Japan Registry of Acute Myocardial Infarction Diagnosed by Universal Definition) study enrolled 3,283 patients with AMI within 48 h of onset and investigated the association between age and sex difference in long-term outcomes.10 The study found a higher crude incidence of 3-year major adverse cardiac events (MACE) in women than in men, but analysis by age showed no significant sex difference in each group.
It is against this background that we read with great interest the study in this issue of the Journal by Hoshi and colleagues.11 The authors used a Japanese nationwide administrative database (J-PCI OUTCOME Registry) to investigate the impact of sex difference on post-discharge clinical outcomes in 29,856 patients with AMI who underwent PCI in 179 hospitals and added new Japanese evidence on sex difference. They report that women had worse clinical outcomes following AMI than men, but these sex-related differences in clinical outcomes diminished after adjusting for age. Regarding risk factors, older age and chronic kidney disease were significantly associated with all-cause death in both sexes. This study also revealed associations among AMI type (STEMI or non-STEMI [NSTEMI]), age and sex in the timing of cardiovascular events after AMI. In patients with STEMI aged ≥80 years, women had a higher rate of MACE than men, and the disparity appeared to emerge within the first 1–2 months. In patients with NSTEMI, the increased risks in all-cause death and MACE seen in women compared with men tended to widen over time. Additionally, men were at higher risk of all-cause death in the group aged ≥80 years, whereas the risk was reversed in the group aged 60–79 years, with women being at a higher risk of death. Although the present study has several limitations (important information on reperfusion: percentages of reperfusion treatment and reperfusion time, etc.) were unavailable; the follow-up period was short (only 1 year); retrospective analysis is often susceptible to unmeasured bias, the results are clinically relevant and have the potential to contribute to Japanese evidence on sex differences in patients with AMI.
Hoshi and colleagues should be congratulated for performing this important study, further highlighting the role of sex difference in predicting and detecting prognosis after AMI and in the associated risk factors. As mentioned earlier, a number of previous studies have begun to identify female-specific characteristics in the management of AMI. Future studies are warranted to determine whether treatments taking this information into account can lead to improved outcomes for all patients with AMI.
There is nothing to disclose.
