Chronic inflammation, a long-term immune response linked to factors like stress, lifestyle choices, mental health, and socioeconomic status, may quietly damage the heart for years before symptoms appear. A recent study involving nearly 480,000 adults in the UK suggests that people with the highest levels of inflammation had a 43% greater risk of heart attack and stroke compared to those with the lowest levels. These changes may start years before any noticeable signs of heart disease, allowing damage to build up over time. To measure inflammation, researchers used a blood marker called glycoprotein acetyls (GlycA), combining these results with heart imaging and genetic data. They found that higher inflammation levels were associated with physical changes in the heart, such as thicker heart walls, smaller chambers, and reduced ability to fill with blood. These structural changes can develop gradually and may eventually lead to heart failure if left unchecked. The study also found that inflammation was closely tied to socioeconomic disadvantage and psychological distress. Common cardiovascular risk factors, such as smoking and obesity, were also linked to increased inflammation. Importantly, even people without a history of heart disease who had consistently high inflammation levels faced a 43% greater risk of heart attack or stroke. Professor Declan O'Regan, from Imperial College London, highlighted that both social factors and mental health play a significant role in inflammation and heart damage, alongside well-known risks like smoking and lack of physical activity. There was also a genetic component, with some individuals being more naturally resistant or vulnerable to the effects of inflammation based on their lifestyle. The researchers stressed that while genetic factors or challenging life conditions can increase risk, they do not make heart disease unavoidable. There are still ways to reduce chronic inflammation and lower the risk of cardiovascular issues. The study identified certain inflammatory proteins, such as those in the interleukin-1 and TNF families, as possible contributors to heart damage. Some of these proteins are already being targeted by drugs in clinical trials, suggesting that anti-inflammatory treatments might help prevent heart disease before symptoms appear. Blood tests measuring inflammation, combined with genetic risk scores, could help identify individuals at higher risk who might benefit from early intervention. The study was supported by the Medical Research Council and the British Heart Foundation, with additional funding from the NIHR Imperial Biomedical Research Centre.