A prospective study that used CT scans to locate fat depots further linked the long-suspected association between excessive abdominal fat and a greater risk of heart disease and cancer than in individuals with a similar body mass index (BMI) who carry their fat in other areas of the body.
Researchers sought to find a link between the location of body fat and specific risk factors for heart disease and cancer, which could explain why individuals with different body types and similar BMIs have varied obesity related health conditions.
Researchers assessed ectopic fat in the abdominal area, around the heart tissue and around the aortic artery of more than 3,000 people in the Framingham Heart Study and followed the participants for heart disease and cancer for up to seven years. The average age of participants was 50 years and nearly half were women. Over the follow-up period, patients were assessed for heart disease, cancer and death risk.
Results appeared online in the Journal of the American College of Cardiology.
Overall, there were 90 cardiovascular events, 141 cancer cases and 71 deaths. Visceral adipose tissue (VAT) was associated with cardiovascular disease (HR, 1.44; 95% CI 1.08-1.92; P=0.01) and cancer (HR, 1.43; 95% CI 1.12-1.84; P=0.005). Addition of visceral adipose tissue to a multivariable model that included body mass index modestly improved cardiovascular risk prediction (net reclassification improvement of 16.3%).
None of the fat depots were associated with all-cause mortality, and there was no association between pericardial fat and myocardial infarction (n=47 events, HR, 0.97; 95% CI, 0.73-1.28; P=0.8.)
Researchers wrote, "Given the worldwide obesity epidemic, identification of high risk individuals is important as it allows targeting of preventive and therapeutic measures. Furthermore, markers of risk may provide insight into the biology linking body fat distribution and outcomes. Our findings that the association of VAT with events was not completely explained by standard risk factors is consistent with evidence suggesting that the link between VAT and obesity-related complications may involve novel biologic pathways."