Prevalence of Cardiovascular-Kidney-Metabolic Syndrome Stages by Social Determinants of Health.

Importance: Cardiovascular-kidney-metabolic (CKM) syndrome-a novel, multistage, multisystem disorder as defined by the American Heart Association-is highly prevalent in the US. However, the prevalence of CKM stages by social determinants of health (SDOH) remains unclear.

Objective: To investigate whether the prevalence of CKM stages varies by SDOH in US adults.

Design, setting, and participants: This cross-sectional study used data from the National Health and Nutrition Examination Survey (1999-2018) and included a nationally representative sample of adults aged 30 to 79 years through complex, multistage probability sampling. Data were analyzed from April 1 to June 15, 2024.

Exposures: The exposures included 5 CKM stages (ie, stages 0-4) reflecting progressive pathophysiology, with advanced (stages 3 or 4) and nonadvanced (stages 0, 1, or 2) disease. CKM stages were defined based on risk factors for metabolic syndrome, cardiovascular disease, and chronic kidney disease.

Main outcome and measures: The main outcome was the age-standardized prevalence of CKM stages and advanced CKM stages across SDOH, including education, marital status, family income, food security, health insurance, employment, home ownership, and health care access.

Results: Among 29 722 participants (weighted mean [SE] age, 50.8 [0.1] years; weighted 50.7% male), the age-standardized prevalence of CKM stages 0 to 4 was 13.6% (95% CI, 13.0%-14.3%), 29.9% (95% CI, 29.1%-30.7%), 43.7% (95% CI, 42.9%-44.5%), 4.7% (95% CI, 4.4%-5.0%), and 8.1% (95% CI, 7.6%-8.5%), respectively. Significant differences were observed in the prevalence of CKM stages across all unfavorable SDOH of interest compared with their favorable counterparts, with unemployment (18.8% [95% CI, 17.7%-20.1%] vs 11.4% [95% CI, 11.0%-11.9%]), low family income (16.1% [95% CI, 15.4%-16.8%] vs 10.1% [95% CI, 9.5%-10.7%]), and food insecurity (18.3% [95% CI, 17.1%-19.6%] vs 11.7% [95% CI, 11.2%-12.2%]) associated with an increased likelihood of advanced CKM stages. Participants with 2 or more unfavorable SDOH were more likely to have advanced CKM stages (age-standardized prevalence, 15.8% [95% CI, 15.2%-16.5%] vs 10.5% [95% CI, 9.9%-11.1%] with <2 unfavorable SDOH). Living in a rented home (15.9% [95% CI, 14.7%-17.0%] vs 9.3% [95% CI, 8.7%-9.9%] owning the home) or not living with a partner (13.2% [95% CI, 12.3%-14.3%] vs 9.2% [95% CI, 8.5%-9.8%] living with a partner) increased the likelihood of advanced CKM stages in female but not male participants.

Conclusions and relevance: In this cross-sectional study, disparities in the prevalence of CKM stages by SDOH, particularly family income, food security, and employment, with notable sex differences, were observed in US adults. These findings highlight the need to address inequities in CKM syndrome through targeted interventions.