Metabolic syndrome is associated with similar long-term prognosis in those living with and without obesity: an analysis of 45 615 patients from the nationwide LIPIDOGRAM 2004-2015 studies.

Metabolic syndrome (MetS) is used to describe a constellation of metabolic disturbances such as elevated blood glucose, increased levels of triglycerides and decreased level of high density lipoprotein cholesterol. They are often accompanied by elevated blood pressure and central obesity, defined as increased waist circumference. Usually, those metabolic disturbances occur in obese individuals, but sometimes, they can also occur in lean subjects. This relatively recent concept is often referred to as lean MetS. A key conclusion from our paper is that MetS, when it occurs in lean patients, is associated with similarly unfavourable long-term prognosis as in obese patients. Additionally, our analysis shows that lean patients with MetS are less often treated with lipid-lowering drugs despite having higher low density lipoprotein cholesterol levels (LDL-C). An additional finding, which is important from a public health perspective, is that obese patients who do not fulfil MetS criteria have higher long-term all-cause mortality than their lean counterparts without MetS. This finding should be an argument to encourage maintenance of normal body weight.