Gottlieb S, Boyko V, Zahger D, Balkin J, Hod H, Pelled B, Stern S, Behar S
Heiden Department of Cardiology, Bikur Cholim Hospital, Jerusalem, Israel.
J Am Coll Cardiol. 1996 Nov 15;28(6):1506-13. doi: 10.1016/s0735-1097(96)00334-8.
This study sought to compare the relation between smoking and the 30-day and 6-month outcome after acute myocardial infarction in an Israeli nationwide survey.
Studies before and during the thrombolytic era reported similar or lower early mortality after acute myocardial infarction in smokers than in nonsmokers. This finding is intriguing and may be misleading because numerous epidemiologic studies have clearly shown that smoking is an independent risk factor for atherosclerosis, myocardial infarction and death.
The study cohort comprised 999 consecutive patients with an acute myocardial infarction from a prospective nationwide survey conducted during January and February 1994 in all coronary care units operating in Israel. The prognosis of 367 patients (37%) who were smokers (current smokers and those who smoked up to 1 month before admission) was compared with that of 632 nonsmokers (past smokers or those who never smoked).
Smokers were on average 10 years younger and were more frequently men and patients with a family history of coronary heart disease and inferior infarction and less frequently patients with a previous infarction or a history of angina, hypertension and diabetes than nonsmokers. Smokers also had a lower incidence of congestive heart failure on admission or during the hospital period. Thrombolytic therapy (49% vs. 40%, p < 0.01) and aspirin (89% vs. 80%, p < 0.001) were administered more frequently in smokers than nonsmokers. The crude 30-day (6.0% vs. 15.7%) and cumulative 6-month (7.9% vs. 21.5%) mortality rates were significantly lower (p < 0.0001 for both) in smokers than nonsmokers, respectively. However, after adjustment for age, baseline characteristics, thrombolytic therapy and invasive coronary procedures, the lower 30-day (odds ratio [OR] 0.75, 95% confidence interval [CI] 0.43 to 1.29, p = 0.30) and 6-month (hazard ratio 0.84, 95% CI 0.54 to 1.30, p = 0.42) mortality rates in smokers and nonsmokers were not significantly different. The model had a power of 0.80 for OR 0.50, with alpha 0.1.
In our nationwide survey, the seemingly better prognosis of smokers early after acute myocardial infarction was no longer evident after adjustment for baseline and clinical variables and may be explained by their younger age and a more favorable risk profile. Smokers develop acute myocardial infarction a decade earlier than nonsmokers. Efforts to lower the prevalence of smoking should continue.
在一项以色列全国性调查中，本研究旨在比较吸烟与急性心肌梗死后30天及6个月预后之间的关系。
溶栓时代之前及期间的研究报告称，急性心肌梗死后吸烟者的早期死亡率与非吸烟者相似或更低。这一发现很有趣，但可能会产生误导，因为众多流行病学研究已明确表明，吸烟是动脉粥样硬化、心肌梗死和死亡的独立危险因素。
研究队列包括1994年1月和2月在以色列所有冠心病监护病房进行的一项前瞻性全国性调查中的999例连续急性心肌梗死患者。将367例吸烟者（当前吸烟者及入院前1个月内仍在吸烟的人）的预后与632例非吸烟者（既往吸烟者或从不吸烟者）的预后进行比较。
吸烟者平均比非吸烟者年轻10岁，男性、有冠心病家族史、下壁梗死的患者更常见，而既往有梗死或心绞痛、高血压及糖尿病病史的患者较少见。吸烟者入院时或住院期间充血性心力衰竭的发生率也较低。吸烟者接受溶栓治疗（49%对40%，p<0.01）和阿司匹林治疗（89%对80%，p<0.001）的频率高于非吸烟者。吸烟者的30天粗死亡率（6.0%对15.7%）和6个月累积死亡率（7.9%对21.5%）分别显著低于非吸烟者（两者p均<0.0001）。然而，在对年龄、基线特征、溶栓治疗及侵入性冠状动脉手术进行校正后，吸烟者和非吸烟者较低的30天死亡率（比值比[OR]0.75，95%置信区间[CI]0.43至1.29，p = 0.30）和6个月死亡率（风险比0.84，95%CI 0.54至1.30，p = 0.42）无显著差异。该模型对于OR为0.50时的检验效能为0.80，α为0.1。
在我们的全国性调查中，校正基线和临床变量后，急性心肌梗死后早期吸烟者看似较好的预后不再明显，这可能是由于他们年龄较小且风险特征更有利。吸烟者发生急性心肌梗死的时间比非吸烟者早十年。降低吸烟率的努力应继续。
