Association of metabolic score for insulin resistance and its 6‐year change with incident type 2 diabetes mellitus

Abstract Background The evidence for the association between metabolic score for insulin resistance (METS‐IR) and type 2 diabetes mellitus (T2DM) is limited. We aimed to explore the association of METS‐IR and its 6‐year change with risk of incident T2DM in a rural Chinese population. Methods We analyzed data for 12 107 participants (mean age 50.48 years). A Cox proportional‐hazard model was used to estimate the association of METS‐IR with incident T2DM by using hazard ratios (HRs) and 95% confidence intervals (CIs); a logistic regression model was used to assess the association of 6‐year METS‐IR change with incident T2DM by using odds ratios (ORs) and 95% CIs. We used subgroup analyses of the association of METS‐IR and its 6‐year change with incident T2DM by sex, age, and baseline fasting plasma glucose (FPG) level as well as restricted cubic splines to describe the dose‐response association. Results The association of METS‐IR and 6‐year METS‐IR change with incident T2DM was significant (per SD unit increase: HR = 1.80, 95% CI: 1.60‐2.02 for METS‐IR, OR = 1.42, 95% CI: 1.28‐1.57 and OR = 1.59, 95% CI: 1.44‐1.76 for relative and absolute METS‐IR change). The significant association remained on subgroup analyses by sex, age, and baseline FPG level. Dose‐response analysis demonstrated that the probability of incident T2DM was significantly increased with increasing METS‐IR and 6‐year METS‐IR change. Conclusions Increased METS‐IR and 6‐year METS‐IR change were positively associated with risk of incident T2DM in a rural Chinese population. METS‐IR may be a vital indicator for identifying T2DM.