Millions May Have Hidden Inflammation That Is Slowly Damaging Their Hearts, Scientists Warn
A silent form of inflammation could be raising the risk of heart attack and stroke by 43 per cent. Millions of people may have no idea it is happening inside their chests, scientists warn.
The warning comes from scientists at Imperial College London and the MRC Laboratory of Medical Sciences. They say the damage can take hold years before any symptoms appear.
Researchers analysed data from nearly 480,000 UK adults using the UK Biobank. They combined a blood marker called GlycA with heart imaging and genetic information. It is described as the largest study of its kind.
Adults in the top 20 per cent for inflammation had a 43 per cent higher risk of heart attack and stroke than those in the bottom 20 per cent. The link held even without prior heart disease.
Hidden Heart Changes
Higher inflammation was also tied to structural changes in the heart, including thickened walls, smaller chambers and poorer filling. These changes can develop silently for years before progressing toward heart failure.
Chronic inflammation differs from the short-term swelling and pain caused by an injury. It involves low-level immune activity that can persist for years without causing noticeable symptoms, according to the British Heart Foundation (BHF).
Professor Declan O'Regan of Imperial College London said millions could be living with hidden inflammation slowly damaging their hearts. He said chronic inflammation is driven by lifestyle and economic factors.
O'Regan added that social disadvantage is emerging as a key heart disease risk factor. He said stress from many sources can trigger inflammation without early symptoms.
Social and Genetic Links
The study found higher inflammation was strongly associated with socioeconomic disadvantage and psychological distress, alongside established risks such as smoking and excess body fat. A strong genetic component also emerged.
O'Regan said some people appear more genetically resilient to inflammatory damage than others. Still, he stressed that genetic risk or difficult circumstances do not make heart disease inevitable.
Researchers identified inflammatory proteins from the interleukin-1 and TNF families as likely drivers of the damage. Several are already targeted by drugs in clinical trials.
Professor Bryan Williams of the BHF said the study shows how genetics and lifestyle, including smoking and poor mental health, can trigger inflammation. He called the resulting heart changes silent but serious.
Williams said the findings point to proteins that play a key role in heart changes, raising hopes for future anti-inflammatory treatments. He urged efforts to address the root causes of inflammation.
Reducing the Risk
O'Regan noted there are currently no established drugs specifically for this type of chronic inflammation, though trials targeting high-risk patients are underway. He said maintaining a healthy weight is likely the most effective defence.
A Mediterranean diet may offer a modest additional benefit, O'Regan said. People with mental health conditions already face higher heart disease risk, and hidden inflammation may help explain that connection.
The American College of Cardiology has called the evidence linking inflammation to heart disease 'clinically actionable'. Harvard's Dr Paul Ridker, a co-author, said inflammation is as important as cholesterol in driving atherosclerosis.
Ridker has called for wider screening using hsCRP, an inexpensive blood test that measures C-reactive protein. He said testing alongside cholesterol in a person's 30s and 40s could allow earlier intervention.
According to the BHF, damage to artery linings lets fat and immune cells build up, narrowing the vessels. Inflamed plaques can rupture, triggering a heart attack or stroke.
The study was funded by the Medical Research Council and the British Heart Foundation. It was published in the European Journal of Preventive Cardiology.