Sex- and Age-Related Differences in the Prevalence of the Cardiovascular-Kidney-Metabolic Syndrome among US Adults, 1999-2020: An Analysis of the NHANES Survey

Background: The cardiovascular-kidney-metabolic (CKM) syndrome is defined as the intricate interplay among metabolic risks, chronic kidney disease (CKD) and the cardiovascular system. The deteriorating CKM syndrome contributes to untimely morbidity and mortality. We aim to characterize sex and age related differences in the prevalence of CKM syndrome. Methods: We used cross-sectional data provided by National Health and Nutrition Examination Survey (NHANES), representative of the non-institutionalized civilian population of the United States. We included non-pregnant participants aged 18 or older between 1999 and 2020 in our analysis. Prevalence was analyzed overall and by population subgroup (including age, sex, and race/ethnicity), and was weighted to be nationally representative. Results: A total of 32848 US adults were included in our study from 1999 to 2020 (weighted mean age, 47.3 years; women, 51.3%). 7.9% of US adults were at stage 0 without any CKM risk factors, with the majority being female, comprising 64% of this subgroup. A higher percentage of younger participants were categorized in this group, with 74.9% being under the age of 45. 18.3% of US adults encountered issues related to excess or dysfunctional adiposity without other metabolic risk factors or CKD (stage 1). The distribution between sexes was similar. Over half of the US adult population (56.5%) exhibited either metabolic risk factors, CKD, or a combination of both (stage 2). Older individuals were more prevalent in stage 2, with 41.1% between the ages of 45-64 and 20.4% aged 65 or older. Females aged 65 or older showed a significantly higher prevalence across almost all metabolic risk factors and CKD compared to men. Between 1999 and 2020, the CKM features increased with decreasing prevalence of CKM stage 0 (P for trends =0.0018) in females (P for trends =0.0039) and to a leser extent in males (P for trends =0.031). Conclusion: Our findings illustrate an exceptionally high and increasing prevalence of CKM syndrome among US adults. Especially elderly women are overrepresented in the high risk group of stage 2 patients. Intense preventive measures should explicitly focus on this group of female patients