Imazio M, Bobbio M, Bergerone S, Barlera S, Maggioni A P
Divisione Universitaria di Cardiologia Ospedale Molinette, Torino.
G Ital Cardiol. 1998 May;28(5):505-12.
No clinical and epidemiological data are available about acute myocardial infarction (AMI) at a young age in large populations, due to the low prevalence of AMI in younger people. The aim of the present study is to analyze epidemiological and clinical characteristics of AMI among younger people in Italy, using the data bases of the three GISSI studies.
Analysis of epidemiological and clinical characteristics of AMI according to different age groups in the three GISSI studies that collected data from 1985 to 1993.
In the GISSI-2 and GISSI-3 data bases, the prevalence of AMI at a young age (2 and 1.8% respectively; difference -0.2% with 95% CI from -0.4 to 0.3%), hospital mortality (2.3 and 1.9% respectively; difference -0.4% with 95% CI from -1.9 to 1.0%), and the rate of young female patients (8 and 7% respectively; difference -1% with 95% CI from -3.6 to 1.6%) are similar. In the GISSI-2 study, we observed that in comparison to elderly patients (> 70 years) young patients (< 40 years) are more frequently smokers (83.9 vs 21.0%; difference 62.9% with 95% CI from 58.5 to 67.3%) and have a higher rate of family history for CAD (42.1 vs 21.1%; difference 21.0% with 95% CI from 15.3 to 26.7%) and of hypercholesterolemia (28.3 vs 15.0%; difference 13.3% with 95% CI from 18.5 to 80.8%), but show a lower prevalence of hypertension (12.2 vs 44.3%; difference from -32.1% with 95% CI from -28.0 to -36.2%) and diabetes (2.9 vs 18.8%; difference -15.9% with 95% CI from -13.5 to -18.3%). AMI at a young age is generally the first event in ischemic heart disease; in comparison with older patients with previous AMI (6.4 vs 17.4%; difference -11.0% with 95% CI from -7.8 to -14.0%) and history of angina (23.2 vs 40.0%, difference -16.8% with 95% CI from -11.8 to -21.9%) this is less frequent. The rate of complications is lower in younger as opposed to older patients for both early (7.7 vs 31.2%; difference -23.5% with 95% CI from -20.0 to -26.9%) and late heart failure (2.9 vs 18.5%; difference -15.6% with 95% CI from -13.2 to -18.0%), as well as for angina (6.4 vs 10.5%; difference -4.1% with 95% CI from -1.1 to -7.1%), reinfarction (1.0 vs 3.3%; difference -2.3% with 95% Ci from -1.1 to -3.6%) and complete AV block (1.6 vs 6.6%; difference -5.0% with 95% CI from -3.3 to -6.7%). In young patients, we observed lower in-hospital (1.6 vs 21.1%; difference -19.5% with 95% CI to -21.6%) and six-month mortality (1.3 vs 8.1%; difference -6.8% with 95% CI from -5.0 to -8.5%).
The incidence and mortality of AMI at a young age was steady during the period between 1988 and 1993. AMI at a young age is a clinical entity with specific characteristics that differ from those found in old patients. In addition, it has peculiar risk profile with a better short- and medium-term outcome.
由于年轻人中急性心肌梗死（AMI）的患病率较低，目前尚无关于大量人群中年轻患者急性心肌梗死的临床和流行病学数据。本研究的目的是利用三项GISSI研究的数据库，分析意大利年轻人群中急性心肌梗死的流行病学和临床特征。
对三项GISSI研究（收集了1985年至1993年的数据）中不同年龄组急性心肌梗死的流行病学和临床特征进行分析。
在GISSI-2和GISSI-3数据库中，年轻患者急性心肌梗死的患病率（分别为2%和1.8%；差异为-0.2%，95%CI为-0.4至0.3%）、医院死亡率（分别为2.3%和1.9%；差异为-0.4%，95%CI为-1.9至1.0%）以及年轻女性患者的比例（分别为8%和7%；差异为-1%，95%CI为-3.6至1.6%）相似。在GISSI-2研究中，我们观察到，与老年患者（>70岁）相比，年轻患者（<40岁）吸烟频率更高（83.9%对21.0%；差异为62.9%，95%CI为58.5至67.3%），冠心病家族史发生率更高（42.1%对21.1%；差异为21.0%，95%CI为15.3至26.7%），高胆固醇血症发生率更高（28.3%对15.0%；差异为13.3%，95%CI为8.5至18.0%），但高血压患病率较低（12.2%对44.3%；差异为-32.1%，95%CI为-28.0至-36.2%），糖尿病患病率较低（2.9%对18.8%；差异为-15.9%，95%CI为-13.5至-18.3%）。年轻患者的急性心肌梗死通常是缺血性心脏病的首发事件；与有既往急性心肌梗死病史的老年患者相比（6.4%对17.4%；差异为-11.0%，95%CI为-7.8至-14.0%）以及有心绞痛病史的患者相比（23.2%对40.0%，差异为-16.8%，95%CI为-11.8至-21.9%），这种情况较少见。年轻患者与老年患者相比，早期（7.7%对31.2%；差异为-23.5%，95%CI为-20.0至-26.9%）和晚期心力衰竭（2.9%对18.5%；差异为-15.6%，95%CI为-13.2至-18.0%）、心绞痛（6.4%对10.5%；差异为-4.1%，95%CI为-1.1至-7.1%）、再梗死（1.0%对3.3%；差异为-2.3%，95%CI为-1.1至-3.6%）和完全性房室传导阻滞（1.6%对6.6%；差异为-5.0%，95%CI为-3.3至-6.7%）的并发症发生率较低。在年轻患者中，我们观察到住院死亡率较低（1.6%对21.1%；差异为-19.5%，95%CI为-21.6%）和六个月死亡率较低（1.3%对8.1%；差异为-6.8%，95%CI为-5.0至-8.5%）。
1988年至1993年期间，年轻患者急性心肌梗死的发病率和死亡率保持稳定。年轻患者的急性心肌梗死是一种具有特定特征的临床实体，与老年患者不同。此外，它具有独特的风险特征，短期和中期预后较好。
