A new index that predicts risk from obesity: For years it was accepted that the BMI index signals risk from obesity. However, a new study presented at a scientific conference of the American Heart Association suggests focusing on other, more precise indices to identify early risk of heart disease.
The study examined data from about 2,000 adults who did not suffer from heart failure at the beginning of follow-up, as part of a large-scale study that lasted nearly seven years. The researchers examined several measures of body composition, including weight, BMI, waist circumference and waist-to-height ratio. At the same time, levels of an inflammatory protein called CRP at high sensitivity were measured, which is used as an indicator of systemic inflammation in the body.
The findings revealed a clear picture: While BMI was not found to be significantly associated with the development of heart failure, measures of central obesity, that is waist circumference and waist-to-height ratio, did predict an increased risk of the disease. In other words, a person can have a normal BMI, yet still carry a significant cardiac risk if there is fat accumulation in the abdominal area.
A possible explanation for this connection is found in the inflammatory mechanism. The researchers found that high levels of CRP were associated with reduced survival without heart failure. It was also found that inflammation explains a significant part of the connection between abdominal fat and the disease, about 25% to 30% of the overall effect. The meaning is that visceral fat not only accumulates around the internal organs, but also acts as an active tissue that secretes inflammatory substances that harm the blood vessels and the heart.
Visceral fat, unlike subcutaneous fat located under the skin, is located deeper and surrounds vital organs such as the liver and intestines. Its high metabolic activity makes it more dangerous from a cardiovascular perspective. Over time it contributes to the development of processes such as insulin resistance, high blood pressure and changes in the blood vessels, which increase the risk of heart failure.
Alongside the findings, the researchers note limitations. The study population included participants of African American origin only, which limits the ability to generalize the results to all populations. At the same time, the study has not yet been published in a peer-reviewed scientific journal, and therefore it should be treated with caution.
Cardiologists who were not involved in the study note that the biological mechanisms connecting visceral fat, inflammation and heart disease are well known, and therefore it is likely that the results are also relevant to other populations. However, they emphasize that the connection between CRP and heart failure is statistical only at this stage, and not direct causal proof. It is possible that the protein serves as a marker of inflammation and not as a direct cause of damage.
The clinical meaning is clear: There is room to expand the assessment of cardiac risk beyond BMI alone. Measuring waist circumference or calculating the waist-to-height ratio can provide additional information about cardiometabolic risk, especially in people who appear relatively thin.
At the same time, experts recommend steps to reduce abdominal fat and systemic inflammation. Combined physical activity, including aerobic training and strength training, a diet rich in vegetables, fruits, fiber and healthy fats, improving sleep quality and reducing consumption of processed food and sugar – all these may help reduce visceral fat and improve heart health.
The findings strengthen a growing approach in medicine according to which not only weight is important, but also where fat accumulates. For doctors and patients, this is a conceptual change that may affect the way risk is assessed and preventive treatment for heart disease is advanced.