[Difference on prevalence and trends of conventional risk factors for ASCVD between young Chinese and American adults with first acute myocardial infarction].

Objective: This study aimed to compare the prevalence and trends of conventional risk factors for atherosclerotic cardiovascular disease(ASCVD) between young Chinese and American adults with first acute myocardial infarction. Methods: This was a retrospective cohort analysis. Hospitalized yang adults (aged from 18 to 44 years old) with first acute myocardial infarction(AMI) from January 2007 through December 2017 were identified from Beijing Anzhen hospital medical record system. Prevalence and trends of hypertension, diabetes mellitus, obesity, smoking, and dyslipidemia were analyzed and compared with young American adults, whose data were reported by Yandrapalli et al, and the hospitalizations for a first AMI in young adults aged 18 to 44 years were identified from national inpatient sample from January 2005 through September 2015. Results: Chinese cohort included 2 866 young adults with a first AMI (male, n =2 739, female, n =127), the mean age was (39±5) years. Presentation of AMI was more frequently ST-segment elevation myocardial infarction (77.3%, 2 214/2 866). American cohort included 280 875 subjects (male, n =203 700, female, n =77 175), the mean age was 39±5 years. Presentation of AMI was more frequently non-ST-segment elevation myocardial infarction (53.6%, 150 549/280 875). In China, dyslipidemia 2 254 (78.6%), smoking 2 084(72.7%), and hypertension 1 170 (40.8%) were most prevalent, and 96.0% (2 752/2 866) of patients had at least 1 risk factor; in the United States, smoking 159 537(56.8%), dyslipidemia 145 212 (51.7%), and hypertension 139 876 (49.8%) were most prevalent, and 90.3% (253 630/280 875) of patients had at least 1 risk factor. Women had a prevalence of diabetes was higher in women, and prevalence of dyslipidemia and smoking was higher in men in China (all P< 0.05);prevalence of obesity, diabetes and hypertension was higher in Women, and prevalence of dyslipidemia and smoking was higher in man in the United States (all P< 0.001). Prevalence of dyslipidemia and smoking was higher Chinese men (79.3% vs. 54.6%, 75.5% vs. 58.1%,all P <0.001), and prevalence of obesity, diabetes and hypertension was lower (13.1% vs. 18.6%, 14.9% vs. 19.9%, 40.6% vs. 49.3%, all P <0.001)in Chinses cohort than those in the United States cohort. Prevalence of smoking and obesity was lower (12.6% vs. 53.4%, 10.2% vs. 26.9%, all P <0.001) and prevalence of dyslipidemia was higher (63.8% vs. 44.1% P <0.001) in Chinese women than those in the United States women. Patients presenting with non-ST-segment elevation myocardial infarction had a higher prevalence of obesity, diabetes and hypertension than patients presenting with ST-segment elevation myocardial infarction in China (20.1% vs.10.9%, 17.6% vs. 14.5%, 47.4% vs. 38.9%, all P< 0.05). The prevalence of the three risk factors also was higher in patients presenting with non-ST-segment elevation myocardial infarction in the US (24.0% vs.17.0%, 25.0% vs. 20.0%, 54.6% vs. 44.2%, all P <0.001), prevalence of smoking and dyslipidemia was lower in these patients (53.5% vs. 60.5%,51.4% vs. 52.1%, all P <0.001). The prevalence of hypertension and obesity increased and the rate of smoking reduced in China from 2007 through 2017 (all trend P< 0.001). The prevalence of all these five conventional risk factors increased temporally in the United States from 2005 to 2015 (all trend P <0.001). The prevalence of hypertension increased by 15.6% in China and 14.5% in the United States, respectively, accounting the largest increase. Conclusions: Smoking, dyslipidemia, and hypertension are most prevalent in China and United State. Significant sex and AMI subtype difference are observed for individual risk factors. The prevalence of hypertension and obesity increased significantly over time in China and all these five conventional risk factors increased significantly in the United States.