Lipid metabolism of middle-aged and older adults may be influenced by their late bedtime behavior, but the association between the above two still needs to be analyzed in-depth.

To explore the association between chronotype and dyslipidemia among populations with different gender, central obesity, late evening snacks and smoking.

A questionnaire survey was conducted among the population aged 40-65 years who received health examination in physical examination center, the First People's Hospital of Fuquan City from March to August, 2022 (n=697). General information and sleep conditions of the included patients were collected and chronotype was evaluated by single-item question of the Morning and Evening Questionnaire. Unconditional binary Logistic regression model was used to evaluate the association between chronotype and the risk of dyslipidemia. Stratified analysis was also performed by gender, central obesity and late evening snacks among the whole population, and performed by smoking among male population. Sensitivity analysis was used to exclude the effect of shift work.

Among the included subjects, morningness preference chronotype accounted for 56.4% (n=393), while eveningness preference chronotype accounted for 43.6% (n=304), with 334 cases (47.9%) detected with dyslipidemia. Unconditional binary Logistic regression analysis showed that chronotype was an influencing factor of dyslipidemia〔OR (95%CI) =1.54 (1.10, 2.16) 〕, the risk of hypertriglyceridemia〔OR (95%CI) =1.48 (1.04, 2.12) 〕and low high-density lipoprotein cholesterol〔OR (95%CI) =1.79 (1.18, 2.72) 〕was higher in the adults with eveningness chronotype than those with morningness chronotype (P<0.05). Stratified analysis of the whole population showed that the risk of low high-density lipoprotein cholesterol was 1.80 times (95%CI: 1.12, 2.91) and 1.73 times (95%CI: 1.02, 2.81) in adults with eveningness chronotype of that in adults with morningness chronotype among male population and the central obesity population, respectively (P<0.05) ; the risk of hypertriglyceridemia was 3.43 times (95%CI: 1.30, 8.99) in adults with eveningness chronotype of that in adults with morningness chronotype among population with late evening snacks (P<0.05) ; while there was no significant effect of chronotype on dyslipidemia and other lipid indexes in female and non central obesity populations (P>0.05). The stratified analysis by smoking in male population showed that the risk of low high-density lipoprotein cholesterol was 1.83 times (95%CI: 1.03, 3.26) in adults with eveningness chronotype of that in adults with morningness chronotype in smoking population (P<0.05) ; while there was no significant of chronotype on hypercholesterolemia, hyper-LDL cholesterolemia and non-HDL-C abnormalities in both smoking and non-smoking populations (P>0.05) .

Eveningness preference chronotype may be a risk factor for dyslipidemia in adults aged 40-65 years, and the associations between dyslipidemia and chronotype may vary across populations with different gender, central obesity, late evening snacks, and smoking status.