Continuous and dichotomous metabolic syndrome definitions in youth predict adult type 2 diabetes and carotid artery intima media thickness: the Cardiovascular Risk in Young Finns Study

Objectives: To examine the utility of continuous metabolic syndrome (cMetS) scores vs a dichotomous metabolic syndrome (MetS) definition in youth to predict adult type 2 diabetes mellitus (T2DM) and carotid intima-media thickness (IMT).

Study design: Participants (n = 1453) from the population-based, prospective, observational Cardiovascular Risk in Young Finns Study who were examined in youth (when aged 9-18 years) and re-examined 15-25 years later. Four cMetS scores were constructed according to procedures most often used in the literature that comprised the youth risk factor inputs of body mass index, blood pressure, glucose, insulin, high-density lipoprotein-cholesterol, and triglycerides. Adult outcomes included T2DM and high carotid IMT (≥ 90th percentile).

Results: For a 1 SD increase in cMetS scores in youth, participants had a 30%-78% increased risk of T2DM and 12%-61% increased risk of high carotid IMT. Prediction of adult T2DM and high carotid IMT using cMetS scores in youth was essentially no different to a dichotomous MetS definition with area under the receiver-operating characteristic curve ranging from 0.54-0.60 (continuous definitions) and 0.55-0.59 (dichotomous) with 95% CIs often including 0.5, and integrated discrimination improvement from -0.2% to -0.6%.

Conclusions: cMetS scores in youth are predictive of cardiometabolic outcomes in adulthood. However, they do not have increased predictive utility over a dichotomous definition of MetS.