Background: Metabolic syndrome is a cluster of risk factors for cardiovascular disease and type 2 diabetes. We aimed to examine whether changes in metabolic syndrome over a two-year span were associated with the development of type 2 diabetes.

Methods: This prospective cohort study included 10,806,716 adults aged >20 years without a history of type 2 diabetes, using the South Korean National Health Insurance Service database. Metabolic syndrome components were measured at baseline and two years later. Diabetes risk over a four-year period was estimated using Cox proportional hazards models.

Results: During a mean follow-up of 4.08 years, 848,859 individuals were diagnosed with type 2 diabetes. Multivariable-adjusted hazard ratios (HRs) for developing diabetes were 1.501 in individuals with metabolic syndrome at baseline and without it two years later, 1.768 in those without metabolic syndrome at baseline and with it two years later, and 2.327 with metabolic syndrome both at baseline and two years later compared with those without metabolic syndrome at either time point. The HRs for diabetes were increased with the number of metabolic syndrome components at baseline and two years later, and decreased significantly with a decrease in the number of components (p for trend < 0.0001). The risk of diabetes was more strongly associated with changes in metabolic syndrome in individuals aged between 20 and 39 years.

Conclusions: Changes in metabolic syndrome could predict the development of type 2 diabetes. In addition, the risk of type 2 diabetes showed a stronger association with metabolic syndrome in young adults. These observations suggest that improving metabolic syndrome is important to prevent type 2 diabetes, particularly for young adults.


M. Lee: None. H. Kwon: None. K. Song: None. J. Lee: None.


Korean National Research Foundation (2018R1D1A1B07049079)

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