Association of weekday sleep duration and estimated glucose disposal rate: the role of weekend catch-up sleep

BACKGROUND: Existing studies have demonstrated a close association between sleep duration and insulin resistance (IR), diabetes, and related metabolic disorders. The estimated glucose disposal rate (eGDR) serves as a reliable marker of IR. This study examined the association between weekday sleep duration and eGDR, and the moderating role of weekend catch-up sleep (WCS). METHODS: We analyzed data from the National Health and Nutrition Examination Survey (2009-2023) using a cross-sectional study design to examine the association between weekday sleep duration and eGDR, while further investigating the moderating role of WCS on this relationship. Restricted cubic splines (RCS) were employed to assess potential nonlinear associations between sleep duration and eGDR, with piecewise regression analyses conducted based on identified inflection points to evaluate threshold effects. Generalized linear models and multivariable regression models were used to analyze the associations between different weekday sleep duration categories, WCS, and eGDR. RESULTS: This analysis included 23 475 participants. RCS modeling revealed an inverted U-shaped relationship between sleep duration and eGDR, with an inflection point at 7.32 hours. Below this threshold, increased sleep improved eGDR (β=0.273, 95% CI 0.224 to 0.322, p