Tincani E, Mazzoli V, Bondi M
Unità di Terapia Medica Sub-Intensiva, Ospedale Civile di Castelfranco Emilia, Modena.
Minerva Cardioangiol. 1997 Jul-Aug;45(7-8):335-47.
The capacity of the results of clinical studies to lead to changes in clinical practice is controversial. The treatment of elderly patients with acute myocardial infarction (AMI) represents an increasingly important challenge for the physician. The decreasing mortality rate for AMI in the general population is countered by an increasingly high mortality rate among the elderly. The aim of this prospective study was to evaluate the impact of the results of clinical studies on the treatment of AMI in community hospitals, and to highlight any differences in treatment and prognosis depending on age.
123 patients with AMI were divided into two groups: (1) young patients (61.2%) aged under 75 (76 patients of whom 64 were male, with a mean age of 61.08 +/- 9.63) and (2) elderly patients (38.8%) aged over 75 (47 patients of whom 26 were male, with a mean age of 81.77 +/- 3.94). All patients were monitored for at least 12 months after discharge.
The percentage administration of fibrinolytics (60.5%), aspirin (80.3%), beta-blockers (oral 40.8%; i.v. 32.9%) and anticoagulants (97.4%) showed that young patients were treated according to the indications reported in the literature. Thrombolysis was more frequently performed in young patients than in the aged (60.5% vs 10.6%; p = 0.0001). Multiple logistic regression analysis showed that age, Killip's class and time at hospitalization were variables predicting the exclusion from fibrinolysis. During hospitalization the elderly group received oral beta-blockers less frequently (8.5% vs 40.8%; p = 0.0001); on discharge, they less frequently received ACE-inhibitors (14.9% vs 46.1%; p = 0.0004), aspirin (48.9% vs 77.6%; p = 0.001), beta-blockers (12.8% vs 44.7%; p = 0.0002). The elderly group revealed a higher mortality rate both during hospitalization (19.1% vs 3.9%; p = 0.01) and follow-up (44.7% vs 11.0%; p = 0.0001). Multivariate analysis showed a direct correlation between ventricular arrhythmia and Killip's class and hospital mortality, whereas smoking and time at hospitalization were inversely correlated. Mortality during follow-up was directly associated with Killip's class and inversely to the use of ACE-inhibitors during hospitalization, and beta-blockers and diuretics on discharge. Kaplan-Meier analysis did not show any differences in the survival rate of the two groups, but the first year after AMI was particularly critical for elderly patients among whom 40% of all deaths were recorded.
This study confirms the application in clinical practice of the results of clinical studies also in community hospitals, and shows that elderly AMI patients are high-risk patients. The high mortality in the latter group is correlated to the fact that they are less eligible to undergo fibrinolytic therapy and have a lower probability of receiving drugs of proven efficacy as a means of increasing survival after AMI. Further clinical studies are required to reduce mortality after AMI in a population that is increasingly widely represented in community hospitals.
临床研究结果能否导致临床实践的改变存在争议。老年急性心肌梗死（AMI）患者的治疗对医生来说是一项日益重要的挑战。一般人群中 AMI 死亡率的下降与老年人中日益升高的死亡率形成反差。这项前瞻性研究的目的是评估临床研究结果对社区医院 AMI 治疗的影响，并突出不同年龄患者在治疗和预后方面的差异。
123 例 AMI 患者被分为两组：（1）年龄小于 75 岁的年轻患者（61.2%，76 例，其中男性 64 例，平均年龄 61.08±9.63）；（2）年龄大于 75 岁的老年患者（38.8%，47 例，其中男性 26 例，平均年龄 81.77±3.94）。所有患者出院后至少监测 12 个月。
纤溶剂（60.5%）、阿司匹林（80.3%）、β受体阻滞剂（口服 40.8%；静脉注射 32.9%）和抗凝剂（97.4%）的使用比例表明，年轻患者的治疗符合文献报道的指征。年轻患者溶栓治疗的频率高于老年患者（60.5%对 10.6%；p = 0.0001）。多因素逻辑回归分析显示，年龄、Killip 分级和住院时间是预测不适合溶栓治疗的变量。住院期间，老年组口服β受体阻滞剂的频率较低（8.5%对 40.8%；p = 0.0001）；出院时，他们接受 ACE 抑制剂（14.9%对 46.1%；p = 0.0004）、阿司匹林（48.9%对 77.6%；p = 0.001）、β受体阻滞剂（12.8%对 44.7%；p = 0.0002）的频率也较低。老年组在住院期间（19.1%对 3.9%；p = 0.01）和随访期间（44.7%对 11.0%；p = 0.0001）的死亡率均较高。多变量分析显示，室性心律失常、Killip 分级与医院死亡率呈直接相关，而吸烟和住院时间与之呈负相关。随访期间的死亡率与 Killip 分级直接相关，与住院期间使用 ACE 抑制剂、出院时使用β受体阻滞剂和利尿剂呈负相关。Kaplan-Meier 分析未显示两组生存率有任何差异，但 AMI 后的第一年对老年患者尤为关键，所有死亡病例中有 40%发生在该组。
本研究证实临床研究结果在社区医院的临床实践中也有应用，并表明老年 AMI 患者是高危患者。后一组的高死亡率与以下事实相关，即他们接受溶栓治疗的可能性较小，且接受经证实有效的药物以提高 AMI 后生存率的概率较低。需要进一步的临床研究以降低社区医院中越来越多的此类人群的 AMI 后死亡率。
