The October–December period coincides with the peak flu season in India, along with cooler weather and festive gatherings. This increases both viral transmission and cardiovascular strain.
Published Sep 28, 2025 | 7:00 AM ⚊ Updated Sep 28, 2025 | 7:00 AM
Seasonal influenza is linked to higher rates of hospitalization for heart attacks and strokes.
Synopsis: The last three wintry months of the year are consistently the riskiest periods for strokes and heart attacks, particularly among the elderly, according to infectious disease expert Dr Vijayalakshmi Balakrishnan. In the latest edition of South First’s “Health For You” podcast, she explains how colder weather, seasonal influenza, and increased cardiovascular strain combine to elevate blood pressure, clotting, and heart stress, particularly in those with pre-existing conditions, with further complications from younger members of the household.
Did you know that October, November, and December consistently report the highest number of strokes and heart attacks in India?
Dr Vijayalakshmi Balakrishnan, a renowned infectious disease expert from Chennai, speaking to South First in the podcast “Health For You,” says influenza-like illnesses, often dismissed as “just a flu,” can trigger serious complications in the elderly, especially when infections spread from younger family members.
“We see the majority of the elderly in the ICU coming in with strokes and heart attacks caused by influenza during October, November and December. Never dismiss flu-like symptoms as ‘just a flu,’” she warned.
The October–December period coincides with the peak flu season in India, along with cooler weather and festive gatherings. This increases both viral transmission and cardiovascular strain.
Studies have shown that seasonal influenza is linked to higher rates of hospitalization for heart attacks and strokes, especially in people above 60.
In an earlier interview with South First, Dr Deepak Krishnamurthy, senior interventional cardiologist at KIMS Hospitals in Bengaluru, said that blood pressure tends to rise in winter, which increases the risk of blood clots.
“The reason is that the metabolic demand goes up in cold weather, leading to a higher heart rate, elevated blood pressure, and a greater tendency for the blood to clot,” he explained.
Expanding further, Dr Krishnamurthy pointed out that vasoconstriction—or narrowing of blood vessels—is more common during winter. “When the weather is cold, the arteries shrink, which pushes up blood pressure and places additional strain on the heart,” he said.
Respiratory infections like influenza and pneumococcal disease also add stress to the heart. “For people who already have underlying conditions, this risk is even higher, which is why it is important for them to take the flu vaccine before winter sets in,” he added.
Doctors explained that in colder months, a mismatch between the supply and demand of oxygen-rich blood puts extra pressure on the heart. Heart attacks are more likely when the body’s demand for oxygen-rich blood rises but the supply remains insufficient.
Several studies back this observation. For instance, a 2018 paper in JAMA Cardiology confirmed a clear seasonal trend in cardiovascular diseases, with countries worldwide reporting peak heart attack cases during winter. “This phenomenon contributes significantly to the higher mortality rates seen in the cold months,” the study stated.
Doctors emphasise that young people often act as silent carriers. While they may recover in a few days, the infection they pass on can be devastating for grandparents or older relatives.
“Influenza is not just a respiratory infection. It can act as a stressor on the body, leading to increased clot formation, higher blood pressure, and inflammation – all of which raise the risk of heart attacks and strokes,” explained Dr Vijayalakshmi Balakrishnan, senior consultant in infectious diseases.
When elders contract flu from younger carriers at home, their pre-existing conditions—diabetes, hypertension, or heart disease—can worsen, sometimes fatally.
“Every year, we see a spike in elderly patients landing in ICUs during these months. What many don’t realise is that a mild cold in a youngster could translate into a stroke or heart attack in their parent or grandparent,” Dr Vijayalakshmi said.
She recommends a few critical steps:
(Edited by Dese Gowda)
