Association between female hormone intake and circadian syndrome: A cross-sectional study based on NHANES 2005-2018.

Circadian syndrome (CircS) is a newly identified condition that extends the concept of metabolic syndrome (MetS) by incorporating short sleep duration and depression, comprising 7 components. Although the interactions between female hormones and the circadian system have been documented, the exact relationship between hormonal factors and CircS requires further investigation. Data from the National Health and Nutrition Examination Survey spanning 2005 to 2018 were analyzed. A total of 7279 nonpregnant women aged ≥ 20 years were included. Weighted logistic regression was employed to assess the association between female hormone intake and CircS. Additionally, restricted cubic spline regression was utilized to investigate the nonlinear relationships of age and body mass index (BMI) with CircS. Subgroup analyses were conducted to evaluate the consistency of these associations. The weighted prevalence of CircS was 54.4%. In the fully adjusted model, female hormone intake was significantly associated with increased odds of CircS, with an odds ratio (OR) of 1.47 and a 95% confidence interval (CI) ranging from 1.20 to 1.80 (P < .001). Restricted cubic spline analysis identified significant nonlinear associations between age and BMI with CircS (P < .001), with inflection points at 61.0 years and 29.9 kg/m2, respectively. For individuals aged < 61.0 years, each additional year was associated with an 8% increase in the risk of CircS (OR = 1.08, P < .001); beyond this age, the risk continued to rise, albeit more slowly (OR = 1.02, P = .005). Regarding BMI, for values ≤ 29.9 kg/m2, each additional unit was associated with a 33% increase in risk (OR = 1.33, P < .001), whereas an 8% increase in risk was observed beyond this threshold (OR = 1.08, P < .001). Subgroup analyses showed consistent associations across all strata (all P for interaction > .05). Female hormone intake is independently associated with an increased risk of CircS. Age and BMI exhibited nonlinear associations with CircS, with inflection points at 61.0 years and 29.9 kg/m2, respectively.