Long Covid Patients Face Rising Heart Risks Even Months After Infection

Patients recovering from Long Covid continue to grapple with lingering health problems, with growing evidence now pointing to a worrying rise in cardiovascular complications—even among those who were never hospitalised during their initial infection.

In India, where millions were infected during successive waves of Covid-19, doctors say the long-term burden of such complications could pose a significant public health challenge.

A new study by Karolinska Institutet, published in eClinicalMedicine, has found that individuals with Long Covid face a higher risk of developing heart-related conditions such as arrhythmia and coronary artery disease. The findings add to a growing body of global research indicating that the virus may leave a lasting imprint on cardiovascular health.

Long Covid—characterised by persistent symptoms such as fatigue, breathlessness, and brain fog weeks or months after infection—has emerged as a complex condition affecting multiple organ systems. While earlier studies largely focused on patients who required hospitalisation, the new research sheds light on risks among those who recovered at home or received only primary care.

The study analysed data from over 1.2 million individuals aged 18 to 65, using the MIRACLE-S cohort in Stockholm. Among them, around 9,000 people—about 0.7%—were diagnosed with Long Covid. Notably, two-thirds of these patients were women. Individuals with prior cardiovascular disease or severe Covid requiring hospitalisation were excluded to ensure clearer comparisons.

Over a follow-up period of nearly four years, the results showed a marked increase in cardiovascular events among those with Long Covid. About 18.2% of women and 20.6% of men in this group developed some form of heart-related condition, compared to 8.4% and 11.1%, respectively, among those without Long Covid.

Even after adjusting for factors such as age, socioeconomic status, and preexisting risks, the association remained significant. Women with Long Covid were found to have more than double the risk of developing cardiovascular disease, while men had roughly a one-third higher risk compared to those without the condition.

According to the researchers, cardiac arrhythmia and coronary artery disease were the most commonly observed complications in both sexes. Among women, there was also a higher likelihood of heart failure and peripheral vascular disease. However, the study did not find a clear link between Long Covid and stroke.

Lead author Pia Lindberg noted that the findings are particularly important because a large proportion of Long Covid patients were never hospitalised. This raises the possibility that many cases of secondary complications may go undetected.

Experts in India say the findings are relevant in the local context, where a significant number of Covid-19 cases were mild or managed at home during peak waves. “We are increasingly seeing patients, even younger individuals, coming with unexplained palpitations, fatigue, or reduced exercise tolerance months after recovery,” said a senior cardiologist at a Delhi government hospital.

Public health specialists caution that India’s already high burden of cardiovascular disease could be further aggravated if Long Covid patients are not systematically monitored. The need for structured follow-up, particularly at the primary care level, is being emphasised.

The study also highlights gender differences, noting that cardiovascular disease in women often presents with less typical symptoms, which can delay diagnosis.

Researchers underscored the need to recognise Long Covid as a potential risk factor for cardiovascular disease, even among previously healthy individuals.