Flu Shot After a Heart Attack: Why It Matters | Healos™
Flu Shots After a Heart Attack: The Vaccine That Protects Your Heart
Most people think of the flu as a respiratory illness: a week of fever, aches and a cough. For someone with heart disease, it's also a cardiac event waiting to happen. Fever and inflammation raise the heart rate and the body's demand for oxygen, make blood more prone to clotting and can tip an unstable plaque into rupture.
Here is the short answer. Flu does more than cause a fever: in the week after a confirmed flu infection, heart attack risk rose about sixfold in an Ontario study. For people who've had a heart attack, the flu shot is one of the simplest protections available. In the IAMI trial, vaccination soon after a heart attack lowered death from any cause by about 41% over a year. October is the time to get it.
简短的答案： 多数人把流感看作呼吸道疾病：一周的发烧、酸痛和咳嗽。但对心脏病患者来说，它也可能引发心脏事件：发热和炎症会提高心率和身体的需氧量，让血液更容易凝结，并可能让不稳定的斑块破裂。
安大略省一项研究发现，确诊流感后一周内心梗风险约升高六倍；对心梗患者来说，流感疫苗是最简单的保护之一，IAMI 试验中心梗后不久接种使一年内全因死亡降低约 41%。10 月就是接种的时候。
Can the flu cause a heart attack?
Yes, and the effect is strong and fast. Researchers in Ontario linked laboratory-confirmed influenza infections with hospital admissions for heart attack and found that, in the seven days after the flu was confirmed, the risk of a heart attack was about six times higher than at other times (Kwong et al., NEJM, 2018).
The mechanisms are well understood. Infection triggers a surge of inflammation, the same biology that drives plaque instability (see one inflammation, three hearts). Fever and dehydration make the heart work harder. And the blood becomes more likely to clot. For an artery that already contains plaque, or a heart still recovering, that combination is dangerous.
流感会引发心梗吗： 会，而且影响强烈、来得很快。安大略省研究者把实验室确诊的流感与心梗住院数据关联，发现确诊后 7 天内心梗风险约为其他时间的六倍（NEJM 2018）。机制很清楚：感染引发炎症激增——与导致斑块不稳定的生物学相同；发热和脱水让心脏更吃力；血液更容易凝结。对于已有斑块的动脉或仍在恢复的心脏，这些叠加起来很危险。
Does the flu vaccine protect the heart? What the IAMI trial showed
The strongest evidence comes from the IAMI trial, which randomly assigned 2,571 people who had just had a heart attack or a high-risk coronary event to receive either the flu vaccine or a placebo, usually during their hospital stay. Over the following 12 months, the vaccine group had a 28% lower risk of the combined outcome of death, heart attack or stent thrombosis, and about 41% lower risk of death from any cause (Fröbert et al., Circulation, 2021).
That fits with earlier research. A meta-analysis of randomised trials found influenza vaccination was associated with a 36% lower risk of major cardiovascular events, with the largest benefit in people with a recent coronary event (Udell et al., JAMA, 2013).
Few treatments in cardiology are this cheap, this safe and this effective. In Canada, the National Advisory Committee on Immunization identifies people with cardiac disease as a priority group for the flu vaccine.
流感疫苗能保护心脏吗：IAMI 试验的发现： 最强的证据来自 IAMI 试验：2,571 名刚发生心梗或高风险冠脉事件的患者，通常在住院期间被随机分配接种流感疫苗或安慰剂。此后 12 个月，疫苗组死亡、心梗或支架血栓的复合风险降低 28%，全因死亡风险降低约 41%（Circulation 2021）。
这与早期研究一致：随机试验的荟萃分析发现，接种流感疫苗与主要心血管事件风险降低 36% 相关，近期发生冠脉事件者获益最大（JAMA 2013）。
心脏病学中很少有治疗如此便宜、安全又有效。在加拿大，国家免疫咨询委员会（NACI）将心脏病患者列为流感疫苗的优先接种人群。
When should heart and stroke patients get the flu shot?
In Canada, flu vaccines usually become available in October, and flu season typically runs from late fall into spring. Because it takes about two weeks to build protection, getting vaccinated in October or early November is ideal, but later is still far better than not at all.
A few practical points:
Ask about the high-dose or adjuvanted vaccine if you're 65 or older. These versions are designed to produce a stronger response in older adults.
It's safe with blood thinners. People taking antiplatelet drugs or anticoagulants can be vaccinated; pressing firmly on the injection site for a few minutes reduces bruising.
If you're in hospital with a heart attack in flu season, ask whether you can be vaccinated before discharge. That's how the IAMI trial did it.
Stroke survivors benefit too. Infections are a known trigger for vascular events, and many stroke survivors share the same arterial disease.
心脏和卒中患者何时打流感疫苗： 在加拿大，流感疫苗通常 10 月开始供应，流感季一般从深秋持续到春季。疫苗约需两周产生保护，所以 10 月或 11 月初接种最理想，但晚一点也远比不打好。
实用要点：
65 岁以上可询问高剂量或佐剂型疫苗，它们旨在让老年人产生更强的反应；
服用抗凝或抗血小板药的人可以接种，在注射部位用力按压几分钟可减少瘀青；
如果在流感季因心梗住院，可询问出院前能否接种——IAMI 试验正是这样做的；
卒中幸存者同样受益，感染是已知的血管事件诱因，很多卒中幸存者也有同样的动脉疾病。
What other vaccines should heart patients ask about?
Flu isn't the only infection worth protecting against. Ask your doctor or pharmacist whether you're due for:
COVID-19 vaccination, which is updated regularly and recommended for many older adults and people with chronic conditions.
RSV vaccination, now available for older adults and recommended for certain higher-risk groups.
Pneumococcal vaccination, which protects against a common cause of pneumonia.
Eligibility differs by age, province and health status, so a quick check with your pharmacist is the easiest way to know what applies to you.
心脏病人还应询问哪些疫苗： 流感不是唯一值得防范的感染。可以问医生或药剂师自己是否需要：新冠疫苗（定期更新，推荐给许多老年人和慢性病患者）；RSV 疫苗（现已面向老年人，推荐给特定高风险人群）；肺炎球菌疫苗（预防肺炎的常见病因）。接种资格因年龄、省份和健康状况而异，问一下药剂师是最简单的办法。
Your fall checklist: protecting your heart through flu season
Vaccines are the foundation. Alongside them, a few simple habits lower the chance that a winter infection turns into a cardiac problem:
Wash hands often and avoid close contact with people who are sick when you can.
Know your sick-day plan: ask your team which medications, such as diuretics or certain blood pressure drugs, you should adjust if you can't eat or drink.
Stay hydrated within any fluid limit your team has set.
Take chest pain, new breathlessness or palpitations during an infection seriously, and call 911 if they're severe.
Keep moving, sleeping well and eating well through the darker months.
Healos™ nutrition plans don't prevent or treat infections and never replace vaccination. What they offer is steady, complementary support for the rest of recovery through the season when the heart is under the most pressure.
秋季清单：安然度过流感季： 疫苗是基础，此外几个简单习惯能降低冬季感染演变成心脏问题的可能：
勤洗手，尽量避免与病人密切接触；
了解「生病日计划」——问医疗团队，如果吃不下喝不下，哪些药（如利尿剂或某些降压药）需要调整；
在医疗团队设定的液体限制内保持水分；
感染期间出现胸痛、新发气短或心悸要认真对待，严重时拨打 911；
在昏暗的月份继续保持活动、睡眠和饮食。
Healos™ 营养方案不预防或治疗感染，也绝不替代疫苗；它在心脏压力最大的季节，为康复的其他部分提供稳定的辅助支持。
The bottom line
For people with heart disease, the flu is a heart risk, not just a respiratory one, and the flu vaccine is one of the most effective protections available. Get it in October or early November, ask about high-dose options if you're over 65 and check whether you're due for COVID-19, RSV or pneumococcal vaccines. It's a few minutes at the pharmacy that can protect a year of recovery.
结论： 对心脏病患者来说，流感是心脏风险，而不只是呼吸道问题；流感疫苗是现有最有效的保护之一。10 月或 11 月初接种，65 岁以上询问高剂量选项，并确认是否需要新冠、RSV 或肺炎球菌疫苗。在药房花几分钟，就能守护一整年的康复。
Frequently asked questions
Should I get a flu shot after a heart attack? Yes, for most people. In the IAMI trial, flu vaccination soon after a heart attack lowered death from any cause by about 41% over 12 months, and Canadian guidance identifies people with cardiac disease as a priority group.
Can the flu cause a heart attack? It can. In an Ontario study, heart attack risk was about six times higher in the week after a laboratory-confirmed influenza infection, because infection drives inflammation, raises the heart's workload and makes blood more likely to clot.
Is the flu vaccine safe if I take blood thinners? Yes. People on antiplatelet drugs or anticoagulants can be vaccinated. Pressing firmly on the injection site for a few minutes helps reduce bruising.
When should heart patients get the flu shot? Ideally in October or early November, since protection takes about two weeks to develop, but getting it later in the season is still worthwhile. Adults 65 and over can ask about high-dose or adjuvanted vaccines.
What other vaccines do heart and stroke patients need? Ask your doctor or pharmacist about COVID-19, RSV and pneumococcal vaccines. Eligibility depends on age, province and health status.
常见问题： 心梗后要打流感疫苗吗？多数人应该打，IAMI 试验中心梗后不久接种使一年内全因死亡降低约 41%，加拿大指南将心脏病患者列为优先人群。流感会引发心梗吗？会，安大略研究中确诊流感后一周内心梗风险约高六倍。吃抗凝药能打吗？可以，注射部位按压几分钟可减少瘀青。何时接种？最好 10 月或 11 月初，晚些也值得；65 岁以上可问高剂量或佐剂型。还需要哪些疫苗？问医生或药剂师新冠、RSV 和肺炎球菌疫苗。
References
Kwong JC, et al. Acute myocardial infarction after laboratory-confirmed influenza infection. New England Journal of Medicine. 2018;378:345–353.
Fröbert O, et al. Influenza vaccination after myocardial infarction: a randomized, double-blind, placebo-controlled, multicenter trial (IAMI). Circulation. 2021;144(18):1476–1484.
Udell JA, et al. Association between influenza vaccination and cardiovascular outcomes in high-risk patients: a meta-analysis. JAMA. 2013;310(16):1711–1720.
National Advisory Committee on Immunization (NACI). Statement on Seasonal Influenza Vaccine (current season). Public Health Agency of Canada.
