Risk Factor Differences in Acute Myocardial Infarction between Young and Older People: A Systematic Review and Meta-Analysis

Abstract Acute myocardial infarction (AMI) is less frequent in young individuals (≤ 45 years) than in older ones (> 45 years). Young AMI patients differ from older AMI patients in different ways. This article aims to assess the differences between young and older AMI patients. A search was made in the database of Cochrane Library, PubMed, BioMed Central and Embase, sence their establishment to December 2016, using the key words: risk factors, clinical characteristics, acute myocardial infarction and young. Meta-analysis was performed by using the Review Manager 5.3 software, pooled odds ratios and 95% confidence intervals were used to assess the strength of differences. Eight studies with fairly quality, enrolling 13,358 patients in the analysis. Compared with older AMI patients, young AMI patients had a higher rate of smoking and obesity (OR = 2.71,95%CI:1.87 to 3.92; OR = 1.76,95%CI:1.13 to 2.74), higher rate of family history of coronary artery disease and alcohol consumption (OR = 2.36,95%CI:1.22 to 4.59; OR = 1.76,95%CI:1.04 to 2.97). Moreover, Young AMI patients had a lower rate of hypertension and diabetes mellitus (OR = 0.52,95%CI:0.37 to 0.73; OR = 0.58,95%CI:0.50 to 0.67). No significant differences were observed in hyperlipidemia, a subgroup data-analysis showed a higher total cholesterol, triglyceride lipase, and low-density lipoprotein levels (p