That long-term stress is linked to cardiovascular disease is not breaking news. However, despite the well-known connection, exactly how the two are coupled has been difficult to pinpoint. Two studies published this week provide new insight. Share on Pinterest Breaking research explains why stress can contribute to poor heart health. Psychological stress carries with it a wealth of ills. In fact, excessive stress is known to contribute to a range of conditions, including hypertension (high blood pressure), ulcers, asthma, and irritable bowel syndrome. It also has a well-documented impact on heart health. Some of this negative influence could be due to coping mechanisms – such as drinking alcohol or smoking tobacco – but there also appears to be a direct link between elevated stress levels and heart complaints. Although this relationship is common knowledge to medical researchers and laypeople alike, the exact physiological processes behind it have remained difficult to unpick. How can an emotion that is constructed in the brain influence the physical health of the heart? “While the link between stress and heart disease has long been established, the mechanism mediating that risk has not been clearly understood.” Dr. Ahmed Tawakol, lead author Studies in animals have found that stress increases the manufacture of white blood cells in bone marrow. This, in turn, leads to an increase in inflammation. How this fits into the full picture is yet to be understood.

Stress, inflammation, and heart health Researchers from Massachusetts General Hospital (MGH) and Icahn School of Medicine at Mount Sinai (ISMMS) in New York designed a double-pronged investigation to gain insight into this fascinating question. The results, published this week in The Lancet, provide new information regarding the links between cardiac health and psychological stress. Dr. Tawakol’s paper describes two studies that aimed to combat the same problem in a similar way. The first study, conducted at MGH, analyzed positron emission tomograph (PET) and computed tomography (CT) scans of nearly 300 individuals. The scans utilized a radiopharmaceutical called fluorodeoxyglucose (FDG), which can simultaneously measure activity in the brain and the level of inflammation in arteries. All participants were healthy at the time of the scan and had information in their medical records of at least three additional clinical visits within the following 5 years. The second study was carried out at the Translational and Molecular Imaging Institute at ISMMS. This smaller study involved 13 participants with a history of post-traumatic stress disorder (PTSD). The researchers assessed their current levels of perceived stress and carried out FDG-PET scans. In the larger MGH study, 22 participants experienced a cardiovascular event – such as stroke, angina, or a heart attack – during the follow-up period. Dr. Tawakol and his team were able to show an association between the likelihood of a cardiac event and a specific part of the brain: the amygdala, a region known to be involved in emotional processing.