IJCS | Volume 32, Nº2, March/April 2019

174 Lei & Bin Differences of risk factors in young AMI patients Int J Cardiovasc Sci. 2019;32(2)163-176 Review Article or pre-diabetes and early effective medical intervention might help prevent AMI in young individuals. In the present study, no significant differences were observed regarding hyperlipidemia between young and older AMI patients. Hyperlipidemia, especially high serum LDL levels, have been regarded as a major risk factor in patients with AMI, and lowering LDL levels has been a main target in medical treatment. HDL is often accepted as a protective factor to prevent the development of atherosclerosis and cardiovascular events. However, low HDL levels have drawn more attention in AMI. 48 A study reported that low HDL was associated with significantly higher risk of in-hospital mortality in STEMI. 49 Our study revealed that young AMI patients had higher levels of serum TG, LDL, TC and lower levels of serum HDL, compared with older AMI patients. Moreover, the prevalence of undiagnosed dyslipidemia and borderline levels of cholesterol in young people were really high. Data have suggested that the prevalence of undiagnosed dyslipidemia in young people was 16.8%, which was higher than the diagnosed group. 50 Thus, these young people may have fewer coronary collaterals, which might cause severe acute myocardial infarction in this group of young individuals. Identifying hyperlipidemia at a younger age, while paying early attention to serum HDL levels, lipid profile control and distal protection in young individuals can prevent AMI in this population. In our analysis, only three studies 11,12,16 compared the risk factor of alcohol consumption. Our data showed that young AMI patients had higher rates of alcohol consumption than older AMI patients. Previous studies showed that alcohol consumption is directly associated with hyperuricemia, 51 which is associated with CAD severity 52 and the amount of alcohol consumed is associated with AMI. 53 Heavy alcohol consumption tended to be associated with an increasing risk of heart failure, cardiac arrest/sudden death and ischemic attack after CAD. 54 Although moderate levels of alcohol consumption are associatedwith a lower risk ofmorbidity and mortality from CAD, young individuals tend to have an excessive alcohol intake. Thus, making young individuals aware of the risk of alcohol consumption and encourage moderate alcohol intake might help prevent acute coronary syndrome. Conclusion The meta-analysis showed that there were differences in risk factors between young and older AMI patients. Smoking, family history of CAD, obesity and alcohol consumption are the main risk factors in young AMI patients, with smoking being the most important one for young individuals with AMI. Young individuals tend to have a better prognosis than older ones with AMI and have more single-vessel coronary artery disease than older AMI patients. Even though there is no difference in hyperlipidemia between young and older AMI patients, young AMI patients had higher levels of serum TG, LDL, TC levels and lower serum HDL levels than older AMI patients. According to our analysis, there were no obvious differences regarding chest pain and LVEF values between young and older AMI patients. Thus, making young individuals aware of these risk factors and their early detection, as well as effective intervention may help prevent acute myocardial infarction in young people. Author contributions Study conception anddesign anddata acquisition: Zeng B. Data analysis and interpretation and statistical analysis: Liu L. Writing of the manuscript: Liu L. Critical revision of the manuscript for intellectual content: Zeng B. Conflicts of interest There are no potential conflicts of interest relevant to this article. Sources of Funding There were no external funding sources for this study. Study Associations This study is not associated with any thesis or dissertation work. Ethics approval and consent to participate This article does not contain any studies with human participants or animals performed by any of the authors.