DID you know you could end up with a heart attack or stroke when you get the flu?
Most of us associate influenza, also known as the flu, with respiratory complications such as pneumonia. However, recent studies have cautioned that influenza increases the risk of heart attack by more than 10 times in the first seven days after contracting the flu.
This is especially so if you are 65 and over, regardless of whether you have a history of heart disease or are living with chronic illnesses such as heart disease, diabetes, lung disease and kidney disease.
As cautioned by Immunise4Life programme technical committee chairman Prof Datuk Dr Zulkifli Ismail, it’s time to rethink what the flu is all about.
“It is not just a fever, runny nose, cough and body aches – it (having the flu) could seriously harm your heart,” he said in a recent statement.
It is important to note that influenza can present in older persons as a relatively mild respiratory illness or even atypically without a fever but with cough, fatigue and confusion, only to set off a sequence of catastrophic events after that.
How does influenza stress your heart?
While our immune system protects us from infectious diseases such as the flu, the inflammation that occurs as part of our immune response can damage our own tissues and organs when a strong response is stimulated.
One example is an effect of COVID-19 that triggers the hyperactivation of the immune system and uncontrolled release of cytokines (small molecules that aid cell-to-cell communication in immune responses and stimulate the movement of cells toward sites of infection).
The uncontrolled release of cytokines, termed “cytokine storm”, leads to a variety of events that may ultimately result in multi-organ failure and death.
According to Immunise4Life – a joint collaboration between the Health Ministry (MOH), Malaysian Paediatric Association (MPA) and Malaysian Society of Infectious Diseases and Chemotherapy (MSIDC) – studies suggest that the same inflammatory response to infection can also trigger a cardiovascular event when you get an influenza infection.
As explained by National Heart Association Malaysia (NHAM) president and consultant cardiologist Dr Alan Fong, our body’s immune response, coupled with the direct effects of flu on the inner lining of blood vessels or atherosclerotic plaques during an influenza virus infection, could lead to plaque rupture, occlusion of arteries and, subsequently, cause a heart attack or stroke.
“Furthermore, there are other factors that play a role, such as physiological stress, increased heart rate or changes in metabolic factors such as the utilisation of glucose, fatty acid and protein in response to infection,” he added.
Are you at risk?
A pre-COVID-19 pandemic study found that influenza virus infection more likely triggers a heart attack compared to other respiratory infections.
Another study found that flu increases the risk of heart attack and stroke in adults aged 40 years and above – even though they had no prior history of these diseases.
In older persons, there are changes that occur in the immune system that leads to a decline in the ability of the body to fight off infections such as the flu; this is known as immunosenescence.
“In addition to this, aging contributes to chronic, non-infectious, low-grade inflammation, known as inflammaging, which plays a key role in the cause and progression of chronic conditions such as cardiovascular diseases,” explained Flu and Older Persons Sub-Committee Malaysian Influenza Working Group (MIWG) chairman Prof Dr Tan Maw Pin.
“Aging also promotes the development and progression of atherosclerosis, which is the most common cause of acute coronary syndrome (a term used for situations where the blood supplied to the heart is suddenly blocked),” Tan added.
Hence, when an older person gets the flu, all these factors put them at higher risk of developing a heart attack and stroke.
Should you get vaccinated for the flu?
The World Health Organisation (WHO), the US Centers for Disease Control and Prevention and the Advisory Committee on Immunisation Practices have recommended influenza vaccination for everyone six months and older, including those with high-risk conditions such as heart disease, for decades now.
Studies have found that the flu vaccination was associated with a 34% lower risk of major adverse cardiovascular events, while patients with recent acute coronary syndrome had a 45% lower risk. On the other hand, there was also an 18% reduced risk of death reported in patients with heart failure.
It is especially advisable to get the annual flu vaccine ahead of the 15th General Election (GE15) polling day this Saturday (Nov 19). This is as overcrowding and travel that’s inevitable during voting season favours the spread of highly contagious infectious diseases such as the flu and COVID-19.
Besides vaccination, the spread of flu can be reduced by practicing COVID-19 SOPs such as wearing a mask, proper handwashing, avoiding contact with people who are sick, covering your coughs and sneezes and disinfecting contaminated surfaces.
In Malaysia, flu can occur year-round. As such, it is advisable to make flu vaccination an annual priority in older persons, especially those with underlying chronic diseases.
Flu vaccination is available at most private clinics in Malaysia. Click here to find a clinic near you. – Nov 14, 2022
Main photo credit: Shutterstock
