Sex Differences in the Association Between Metabolic Score for Insulin Resistance and the Reversion to Normoglycemia in Adults with Prediabetes: a Cohort Study

Background: The metabolic score for insulin resistance (MetS-IR) has become a valid indicator to evaluate insulin resistance. Our investigation sought gender differences in the correlation between MetS-IR and the reversion from prediabetes to normoglycemic status.

Methods: This retrospective research, carried out in 32 areas across 11 cities with several centers in China, encompassed 15,423 participants with prediabetes. We employed a Cox proportional hazards regression model to examine the link between MetS-IR and the reversion to normoglycemic status. We also applied cubic spline functions and smooth curve fitting to detect non-linear relationships. Additionally, we embarked on a range of sensitivity analyses.

Results: The study included 15,423 participants, with 10,009 males (64.90%) and 5,414 females (35.10%). The average follow-up time was 2.96 ± 0.93 years, and 6,623 individuals (42.94%) reversed normoglycemia. A non-linear correlation was discovered among MetS-IR and reversion to normoglycemic status in men, with a turning point at 55.48. For a one-unit rise in MetS-IR below this point, the chance of reversal to normoglycemic levels declined by 3% (HR = 0.97, 95% CI:0.96-0.97, P < 0.0001). In women, the association was linear, with every unit rise in MetS-IR leading to a 3% reduction in transitioning to normal glycemic levels. (HR = 0.97, 95% CI: 0.97-0.98, p < 0.0001).

Conclusion: A negative correlation was discovered between MetS-IR and reversion to normoglycemic status in adults with prediabetes. Specifically, a non-linear association was observed for males, while females exhibited a linear correlation.