Many studies worldwide have reported a close relationship between a high-risk obesity pattern, visceral obesity, and an altered cardiometabolic risk profile beyond total adiposity. Moreover, excess visceral adiposity is a significant risk factor for both cardiovascular disease (CVD) and type 2 diabetes. Non-alcoholic fatty liver disease (NAFLD), another prevalent condition frequently observed among patients with visceral obesity, has also been associated with metabolic complications such as insulin resistance, glucose intolerance and a deteriorated lipoprotein-lipid profile. However, whether the relationship between NAFLD and CVD or type 2 diabetes is independent of the concomitant presence of visceral obesity remains unclear.
In this regard, a recent study published in Mayo Clinic Proceedings sought to determine the associations of visceral adipose tissue and liver fat (observed in isolation or combined) with type 2 diabetes and CVD in two different cohorts, the Dallas Heart Study and the UK Biobank. In both cohorts, a high level of visceral adipose tissue, irrespective of liver fat content, was associated with an increased risk of CVD. Moreover, high liver fat in isolation was associated with CVD risk in the UK Biobank. A similar approach was used to examine the risk of type 2 diabetes. A high level of visceral adipose tissue with high or low liver fat was associated with incident type 2 diabetes in both cohorts. Finally, a high liver fat in isolation was predictive of incident type 2 diabetes in the Dallas Heart Study.
Results of this study suggest different patterns of associations between visceral obesity and liver fat content with CVD and type 2 diabetes. These results emphasize the need to pay attention to adipose tissue distribution to deepen our understanding of the etiology of NAFLD.
For those interested to learn more about NAFLD as a cardiometabolic disease, the International Atherosclerosis Society has produced a series of video presentations to help physicians in the identification and management of patients with NAFLD. Dr. Jean-Pierre Després, Scientific Director of the International Chair on Cardiometabolic Risk and Dr. Peter Libby, member of its Executive Board, each participated in a video.