Johns Hopkins Ciccarone Center for the Prevention of Cardiovascular Disease, The Johns Hopkins University, Baltimore, MD (M.C.-A., J.W.M., Z.D., R.S.B., O.D., K.N., M.J.B.).
Minneapolis Heart Institute and Foundation, MN (M.D.M.).
Circulation. 2020 May 12;141(19):1541-1553. doi: 10.1161/CIRCULATIONAHA.119.045010. Epub 2020 Apr 1.
Recent American College of Cardiology/American Heart Association Primary Prevention Guidelines recommended considering low-dose aspirin therapy only among adults 40 to 70 years of age who are at higher atherosclerotic cardiovascular disease (ASCVD) risk but not at high risk of bleeding. However, it remains unclear how these patients are best identified. The present study aimed to assess the value of coronary artery calcium (CAC) for guiding aspirin allocation for primary prevention by using 2019 aspirin meta-analysis data on cardiovascular disease relative risk reduction and bleeding risk.
The study included 6470 participants from the MESA Study (Multi-Ethnic Study of Atherosclerosis). ASCVD risk was estimated using the pooled cohort equations, and 3 strata were defined: <5%, 5% to 20%, and >20%. All participants underwent CAC scoring at baseline, and CAC scores were stratified as =0, 1 to 99, ≥100, and ≥400. A 12% relative risk reduction in cardiovascular disease events was used for the 5-year number needed to treat (NNT) calculations, and a 42% relative risk increase in major bleeding events was used for the 5-year number needed to harm (NNH) estimations.
Only 5% of MESA participants would qualify for aspirin consideration for primary prevention according to the American College of Cardiology/American Heart Association guidelines and using >20% estimated ASCVD risk to define higher risk. Benefit/harm calculations were restricted to aspirin-naive participants <70 years of age not at high risk of bleeding (n=3540). The overall NNT with aspirin to prevent 1 cardiovascular disease event was 476 and the NNH was 355. The NNT was also greater than or similar to the NNH among estimated ASCVD risk strata. Conversely, CAC≥100 and CAC≥400 identified subgroups in which NNT was lower than NNH. This was true both overall (for CAC≥100, NNT=140 versus NNH=518) and within ASCVD risk strata. Also, CAC=0 identified subgroups in which the NNT was much higher than the NNH (overall, NNT=1190 versus NNH=567).
CAC may be superior to the pooled cohort equations to inform the allocation of aspirin in primary prevention. Implementation of current 2019 American College of Cardiology/American Heart Association guideline recommendations together with the use of CAC for further risk assessment may result in a more personalized, safer allocation of aspirin in primary prevention. Confirmation of these findings in experimental settings is needed.
最近发布的美国心脏病学会/美国心脏协会一级预防指南建议，只有年龄在 40 岁至 70 岁、动脉粥样硬化性心血管疾病（ASCVD）风险较高但出血风险不高的成年人，才考虑使用低剂量阿司匹林治疗。然而，目前尚不清楚如何最好地识别这些患者。本研究旨在利用 2019 年阿司匹林荟萃分析心血管疾病相对风险降低和出血风险的数据，评估冠状动脉钙（CAC）在指导阿司匹林一级预防中的作用。
该研究纳入了 MESA 研究（多民族动脉粥样硬化研究）中的 6470 名参与者。使用汇总队列方程估计 ASCVD 风险，定义了 3 个风险分层：<5%、5%至 20%和>20%。所有参与者在基线时均进行 CAC 评分，根据 CAC 评分将其分层为=0、1 至 99、≥100 和≥400。使用 5 年治疗需要人数（NNT）计算，假定心血管疾病事件的相对风险降低 12%；使用 5 年危害需要人数（NNH）估计，假定大出血事件的相对风险增加 42%。
根据美国心脏病学会/美国心脏协会指南，只有 5%的 MESA 参与者符合阿司匹林一级预防的考虑条件，使用>20%的估计 ASCVD 风险来定义更高风险。获益/危害计算仅限于阿司匹林初治、年龄<70 岁且出血风险不高的参与者（n=3540）。预防 1 例心血管疾病事件的阿司匹林总体 NNT 为 476，NNH 为 355。NNT 在估计的 ASCVD 风险分层中也大于或等于 NNH。相反，CAC≥100 和 CAC≥400 确定了 NNT 低于 NNH 的亚组。这在总体上（对于 CAC≥100，NNT=140 与 NNH=518）和 ASCVD 风险分层内均如此。此外，CAC=0 确定了 NNT 远高于 NNH 的亚组（总体上，NNT=1190 与 NNH=567）。
与汇总队列方程相比，CAC 可能更有助于指导一级预防中阿司匹林的应用。实施当前 2019 年美国心脏病学会/美国心脏协会指南建议，并结合 CAC 进一步进行风险评估，可能会使一级预防中阿司匹林的应用更加个性化、更安全。需要在实验环境中确认这些发现。
