The Typology of Metabolic Syndrome in the Transition to Adulthood

Background: Metabolic syndrome (MetS) is a clustering of risks associated with cardiometabolic disease in adults. Obesity is considered the major etiologic factor. However, unlike obesity, the natural history of MetS as adolescents transition to adulthood is unknown. Objective: The purpose of this study was to characterize the typology of MetS as adolescents transition to young adulthood and to explore determinants of that typology. Design/Participants: A total of 458 participants from a school-based longitudinal cohort study of baseline 5th to 12th graders were followed for 9 years. Methods: Based on the presence or absence of MetS at study visits (year [Y] 1, Y4, Y8, and Y10), a MetS typology was defined, and its characteristics were explored using multinomial regression modeling. Results: Both obesity and MetS increased (obesity from 21.0% to 33.4% and MetS from 2.8% to 17.9%). MetS typology was as follows: never, 76.9%; incident, 16.4%; unstable/remitted, 5.7%; and persistent, 1.1%. Of Y1 MetS-positive cases, 61.5% remitted, as did 36.4% of Y4 MetS-positive cases and 25% of Y8 MetS-positive cases. Most incident cases (56.0%, n = 42) occurred in Y10; only 12% (n = 9) occurred in Y4. Obesity increased the odds of MetS (incident: odds ratio [OR] = 4.42, 95% confidence interval [CI] = 2.23-8.76; unstable/remitted: OR = 7.79, 95% CI = 3.12-19.41; persistent: OR = 31.36, 95% CI = 2.99-328.98). In addition, changes in body mass index over the study were associated with persistent (OR = 1.27, 95% CI = 1.03-1.56) and incident MetS (OR = 1.49, 95% CI = 1.31-1.71), but not unstable/remitted MetS (OR = 1.09, 95% CI = 0.99-1.19). Of note, body mass index increased for 77% of those with unstable/remitted MetS, including 90% (n = 9/10) of persistently obese youth with unstable/remitted MetS. Conclusions: During the transition to adulthood, the diagnosis of MetS is highly unstable and fluctuates even among those who are obese and gaining weight.