Abstract This study aims to explore the prevalence of Low-carbohydrate diet (LCD) among individuals with cardiovascular-kidney-metabolic (CKM) syndrome and its relationship with prognosis. Methods The study included individuals diagnosed with CKM from the National Health and Nutrition Examination Survey (NHANES) database between 2009 and 2018. Participants were divided into two groups: those on a LCD and those not on a LCD. Multivariate logistic regression analysis was conducted to assess the factors influencing the choice of LCD among CKM individuals. Kaplan-Meier survival curve analysis and multivariate Cox regression analysis were performed to evaluate the association between LCD and the risk of all-cause mortality. Stratified analysis was performed to assess the consistency of results. Results A total of 866 non-CKM (stage 0) individuals and 26,989 CKM individuals (stages 1, 2, 3, and 4) were included. The proportions of individuals on LCD for CKM stages 0, 1, 2, 3, and 4 were 2.07%, 0.59%, 1.25%, 2.42%, and 1.59%, respectively. Multivariate logistic regression analysis indicated that age, gender, race, body mass index, and diabetes status might influence the choice of LCD among CKM individuals. Multivariate Cox regression analysis revealed that compared to non-LCD individuals, those on LCD had a 61% reduced risk of all-cause mortality (HR=0.39; 95% CI, 0.22-0.71, P=0.002). Stratified analysis showed no interaction between LCD and CKM stages (P for interaction <0.05). Conclusion The proportion of individuals on LCD in CKM is relatively low. Furthermore, LCD can reduce the risk of all-cause mortality among CKM individuals, regardless of CKM stage.

The authors have declared no competing interest.

This study did not receive any funding

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National Center for Health Statistics Research Ethics Review Board gave ethical approval for this work

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