Metabolic syndrome (MetS) is characterized by dyslipidemia, abdominal obesity, hypertension, and impaired glucose metabolism. It affects nearly one-third of adults globally, increasing the risk of all-cause mortality and cardiovascular diseases (CVDs). Insulin resistance (IR) is the main factor in its pathophysiology. Traditional markers such as the triglyceride-glucose (TyG) index and homeostatic model assessment of IR (HOMA-IR) are used to assess the IR. However, the estimated glucose disposal rate (eGDR), calculated using HbA1c, waist circumference, and hypertension status, has emerged as a reliable and practical surrogate marker for predicting mortality risk in both diabetic and non-diabetic populations.
Sleep duration plays a key role in regulation of metabolic regulation. Short sleep impairs glucose intolerance, promotes IR, and increases inflammation, thereby elevating the risk of CVD and type-2 diabetes. Weekend catch-up sleep (WCS) is often used for compensating weekday sleep loss, but evidence related to its metabolic benefits remains inconsistent. A recent study published in BMJ Open Diabetes Research & Care evaluated the association of weekday sleep duration with eGDR and explored whether WCS moderates this relationship.
In this study, NHANES used data from 2009 to 2023 (N = 67,932). Among participants, 44,457 were excluded because of pregnancy, age less than 20 years, or missing information on covariates, sleep, or eGDR. The final sample included 23,475 adults (male = 51.16%, female = 48.84%, Non-Hispanic White = 67.32%, median eGDR = 8.23 [5.52-9.94]) with 10,817 providing weekend sleep data. Weekend and weekday sleep durations were self-reported. WCS was estimated as weekend minus weekday sleep, which was categorized as 0, 0-1,1-2, and>2 hours. Covariates included ethnicity, income to poverty ratio, smoking, sex, marital status, education, body mass index (BMI), marital status, ethnicity, alcohol use, and age.
Restricted cubic spline models (5-knot model) showed an inverted U-shaped association between eGDR and weekday sleep duration (p for non-linearity <0.001) with an inflection point at 7.32 hours. Below 7.32 hours, each one hour rise in sleep duration was positively linked to a eGDR with β value of 0.273 (95% confidence interval [CI]: 0.224 to 0.322) and p<0.001 whereas negative correlation was observed when sleep duration at ≥7.32 hours with β value of -0.222 (95% CI: -0.272 to -0.171) and p<0.001.
Subgroup analysis showed consistent associations between weekday sleep duration and eGDR across all subgroups except for BMI of ≥30 kg/m2 with β = 0.1300 (95% CI: 0.072 to 0.187) and p-interaction of 0.002. For sleep ≥7.32 hours, stronger negative correlations were observed participants with BMI ≥30 kg/m2 (β = -0.0983 [95% CI: -0.1590 to -0.0375], p = 0.032), women (β = -0.0992 [95% CI: -0.1450 to -0.0535], p = 0.001), and those aged 40-59 years (β = -0.131 [95% CI: -0.2060 to -0.0553], p = 0.014).
Multivariable regression analysis demonstrated that among participants sleeping <7.32 hours, WCS for 1-2 hours (β = 0.296 [95% CI: 0.107 to 0.484], p = 0.002) and 0-1 hour (β = 0.249 [95% CI: 0.074 to 0.425], p = 0.005) were associated with higher eGDR. Although overall moderation was non-significant (p >0.05), WCS >2 hours strengthened the negative association (β = -0.568, p =0.005). Optimal WCS was found to be approximately 1.1-1.2 hours at weekday sleep duration of ≥7.32 hours, whereas WCS was 1.16 hours at weekday sleep duration of <7.32 hours.
This study was limited by its cross-sectional design, self-reported sleep data, potential residual confounding, restricted generalizability beyond the US population, and inability to differentiate between daytime napping and nocturnal sleep.
In conclusion, weekday sleep duration showed an inverted U-shaped relationship with eGDR, with optimal levels at 7.32 hours. Moderate WCS (additional ≤2 hours was beneficial, whereas excessive WCS was associated with adverse metabolic outcomes.
Reference: Fan Z, Wei R, Chen T, et al. Association of weekday sleep duration and estimated glucose disposal rate: the role of weekend catch-up sleep. BMJ Open Diabetes Research & Care. 2026;14:e005692. https://doi.org/10.1136/bmjdrc-2025-005692
