Association of serum uric acid with cardiovascular-kidney-metabolic syndrome in elderly populations: results from Chinese and US cohorts.

Cardiovascular-kidney-metabolic (CKM) syndrome is highly prevalent among the elderly. Serum uric acid (SUA) may serve as a potential marker for CKM, but evidence on the association between SUA levels and the progression of CKM syndrome remains scarce and controversial. This study aims to investigate the relationship between SUA levels and CKM syndrome in elderly populations by utilizing cohort data from China and the United States. We analyzed 3,299 participants from the Shanghai Friendship Community Elderly Cohort (SFCEC) and 2,372 from the US National Health and Nutrition Examination Survey (NHANES) 2011-2018.SUA was measured using standardized assays. Ordinal logistic regression models were performed. Restricted cubic spline regression (RCS) was performed to visualize the dose-response relationship. The prevalence of CKM syndrome (stages 1-4) was strikingly high in both elderly cohorts (98.33% in the SFCEC cohort and 98.76% in the NHANES cohort). After comprehensive adjustment, multivariable analysis revealed that each 1 mg/dl increase in SUA was associated with 24.9% (OR = 1.249, 95% CI 1.186-1.315) and 27.8% (OR = 1.278, 95% CI 1.174-1.392) elevated risks of CKM stages in the SFCEC and NHANES cohorts, respectively. Compared with the lowest tertile, participants in the highest tertile demonstrated significantly increased CKM risks (SFCEC: OR = 1.966, 95% CI 1.653-2.339; NHANES: OR = 1.975, 95% CI 1.472-2.650). RCS analysis indicated a positive linear dose-response relationship between SUA levels and CKM staging. A significant interaction by sex was observed (P < 0.001), suggesting potential sex differences that warrant further investigation. This study reveals that elevated SUA levels are associated with higher CKM stages in the elderly population.Further research is needed to evaluate the potential role of SUA measurement in CKM risk assessment.