Augustovski F A, Cantor S B, Thach C T, Spann S J
Hospital Italiano de Buenos Aires, Unidad de Medicina Familiar y Preventiva, Buenos Aires, Argentina.
J Gen Intern Med. 1998 Dec;13(12):824-35. doi: 10.1046/j.1525-1497.1998.00246.x.
The use of aspirin for primary prevention of cardiovascular events in the general population is controversial. The purpose of this study was to create a versatile model to evaluate the effects of aspirin in the primary prevention of cardiovascular events in patients with different risk profiles.
A Markov decision-analytic model evaluated the expected length and quality of life for the cohort's next 10 years as measured by quality-adjusted survival for the options of taking or not taking aspirin.
Hypothetical model of patients in a primary care setting.
Several cohorts of patients with a range of risk profiles typically seen in a primary care setting were considered. Risk factors considered included gender, age, cholesterol levels, systolic blood pressure, smoking status, diabetes, and presence of left ventricular hypertrophy. The cohorts were followed for 10 years. Outcomes were myocardial infarction, stroke, gastrointestinal bleed, ulcer, and death.
For the cases considered, the effects of aspirin varied according to the cohort's risk profile. By taking aspirin, the lowest-risk cohort would be the most harmed with a loss of 1.8 quality-adjusted life days by taking aspirin; the highest risk cohort would achieve the most benefit with a gain of 11.3 quality-adjusted life days. Results without quality adjustment favored taking aspirin in all the cohorts, with a gain of 0.73 to 8.04 days. The decision was extremely sensitive to variations in the utility of taking aspirin and to aspirin's effects on cardiovascular mortality. The model was robust to other probability and utility changes within reasonable parameters.
The decision of whether to take aspirin as primary prevention for cardiovascular events depends on patient risk. It is a harmful intervention for patients with no risk factors, and it is beneficial in moderate and high-risk patients. The benefits of aspirin in this population are comparable to those of other widely accepted preventive strategies. It is especially dependent on the patient's risk profile, patient preferences for the adverse effects of aspirin, and on the level of beneficial effects of aspirin on cardiovascular-related mortality.
在普通人群中使用阿司匹林进行心血管事件的一级预防存在争议。本研究的目的是创建一个通用模型，以评估阿司匹林在不同风险特征患者中进行心血管事件一级预防的效果。
一个马尔可夫决策分析模型通过质量调整生存情况评估了该队列接下来10年服用或不服用阿司匹林两种选择下预期的寿命长度和生活质量。
基层医疗环境中患者的假设模型。
考虑了几组在基层医疗环境中常见的具有不同风险特征的患者队列。所考虑的风险因素包括性别、年龄、胆固醇水平、收缩压、吸烟状况、糖尿病以及左心室肥厚情况。对这些队列进行了10年的随访。结局指标为心肌梗死、中风、胃肠道出血、溃疡和死亡。
在所考虑的病例中，阿司匹林的效果因队列的风险特征而异。服用阿司匹林时，风险最低的队列受到的伤害最大，服用阿司匹林会损失1.8个质量调整生命日；风险最高的队列获益最大，可增加11.3个质量调整生命日。未经质量调整的结果显示所有队列服用阿司匹林都有获益，增加0.73至8.04天。该决策对服用阿司匹林的效用变化以及阿司匹林对心血管死亡率的影响极为敏感。在合理参数范围内，该模型对其他概率和效用变化具有稳健性。
是否服用阿司匹林进行心血管事件的一级预防取决于患者的风险。对于无风险因素的患者，这是一种有害的干预措施，而对中高风险患者有益。阿司匹林在该人群中的益处与其他广泛接受的预防策略相当。这尤其取决于患者的风险特征、患者对阿司匹林不良反应的偏好以及阿司匹林对心血管相关死亡率的有益作用水平。
