Chronic Inflammation Raises Heart Attack and Stroke Risk by 43%

Heart disease is often described as a problem of cholesterol and blood pressure. A growing body of evidence suggests a third factor deserves equal attention: chronic low-grade inflammation. Unlike the short-lived inflammation that follows an injury or infection, this version smoulders quietly for years, gradually reshaping blood vessels long before a person notices chest pain, breathlessness or any other warning sign.

Recent analyses tracking adults over extended follow-up periods found that those in the highest inflammation category faced roughly a 43% greater risk of heart attack and stroke compared with those in the lowest. Importantly, that elevated risk persisted even after accounting for familiar contributors such as smoking, cholesterol levels, blood pressure and body weight — suggesting inflammation is not simply a by-product of other risk factors, but a driver in its own right.

How inflammation damages arteries

Inflammatory cells and signalling molecules circulating at persistently elevated levels irritate the inner lining of blood vessels, known as the endothelium. Over time that irritation encourages cholesterol-rich plaque to accumulate and, crucially, makes existing plaque less stable. An unstable plaque can rupture without warning, triggering a clot that blocks blood flow to the heart or brain. This is why two people with identical cholesterol readings can face very different outcomes.

The stress and circumstance connection

What makes the findings particularly notable is where the inflammation appears to originate. Researchers have repeatedly linked elevated inflammatory markers to chronic psychological stress, disrupted sleep, sedentary routines, ultra-processed diets, loneliness, depression and anxiety. Socioeconomic conditions also register strongly: financial insecurity, unstable housing, long commutes, job strain, noise and air pollution exposure and limited access to preventive care are all associated with higher baseline inflammation.

That pattern reframes cardiovascular risk as something shaped not only by individual habits but by the environments people live and work in. It also helps explain long-observed disparities in heart disease rates between communities — differences that cholesterol and blood pressure alone never fully accounted for.

Testing that already exists

Inflammation can be measured relatively cheaply. The most widely used marker is high-sensitivity C-reactive protein (hs-CRP), a simple blood test. Readings below 1 mg/L are generally considered low risk, 1–3 mg/L intermediate, and above 3 mg/L elevated, though transient infections can temporarily distort results, so repeat testing matters. Despite its availability, hs-CRP is not yet part of routine screening in many health systems, and researchers argue that adding it could help identify people who look healthy on paper but carry hidden risk.

What can lower it

Several anti-inflammatory approaches are already in clinical use or under active study. Low-dose colchicine has shown benefit in patients with established coronary disease, and targeted biologic therapies have reduced cardiovascular events in trials. Statins, long prescribed for cholesterol, also lower inflammatory markers.

Non-pharmacological measures remain the foundation. Regular aerobic activity, consistent sleep, weight management, smoking cessation, treatment of gum disease, stress-reduction practices and diets rich in fibre, oily fish, olive oil, legumes and vegetables are all associated with lower inflammatory activity.

The broader message from this research is one of timing. Inflammation is measurable, modifiable and detectable years in advance — which makes it one of the more promising openings for preventing heart attacks and strokes rather than treating them after the fact. Anyone with a family history of cardiovascular disease, or with persistent stress, poor sleep or metabolic concerns, may want to discuss inflammatory testing with a clinician.