Chronic kidney disease (CKD) is a global challenge of public health. In the United States Renal Data System (USRDS) based on the National Health and Nutrition Examination Survey (NHANES) data from 2017 to March 2020, among adults, 14.0% had albuminuria, low estimated glomerular filtration rate (eGFR), or both (James et al., 2010; Coresh et al., 2007; US Renal Data System, 2022). The absolute prevalence of CKD (Murphy et al., 2016) was considerably higher in the elderly than in the youngers (Murphy et al., 2016). According to the USRDS (US Renal Data System, 2022), the prevalence of CKD was 33.24% among the elderly aged 65 years and older, compared to 9.04% of adults younger than 65 years. CKD is associated with high healthcare costs, death, significant morbidity (Gansevoort et al., 2011; Chronic Kidney Disease Prognosis Consortium, 2010), and other various adverse health outcomes, for example, cardiovascular disease (CVD), acute kidney injury, and premature death (Jha et al., 2013; Hsu et al., 2008; Go et al., 2004; Mahmoodi et al., 2012), but CVD has vital relevance because it is the leading cause of death among people with CKD (Matsushita et al., 2022). Several pathophysiology mechanisms, including shared risk factors (for example, hypertension and diabetes), altered bone mineral metabolism, anaemia, volume overload and the presence of uraemic toxins link CKD to CVD (Matsushita et al., 2022), and the shared underlying pathophysiology suggest that cardioprotective recommendations might also be practical for kidney disease prevention (Ronco et al., 2008).

The American Heart Association (AHA) released Life's Simple 7 (LS7) for improving cardiovascular health (CVH) in 2010. Several studies have certified the associations of LS7 with atherosclerotic cardiovascular disease (ASCVD) (Rikhi and Shapiro, 2022), diabetes (Fretts et al., 2014), and CKD (Ogunmoroti et al., 2016; Rebholz et al., 2016); however, they also proved the limitations of LS7 (Rikhi and Shapiro, 2022; Fretts et al., 2014; Ogunmoroti et al., 2016; Rebholz et al., 2016). In 2022, the AHA presented an enhanced algorithm to measure CVH, Life's Essential 8 (LE8) (Lloyd-Jones et al., 2022a), which updated the definition and quantification of the original assessment components for their responsiveness to inter- and intra-individual variation.

CKD was often identified as an age-related condition (KDIGO, 2013). As the global population ages, the number of population aged 65 and over is expected to increase from 703 million in 2019 to >1.5 billion in 2050 (World Population Ageing, 2019), and the burden of CKD is expected to increase (Liu et al., 2021). The projected increase in the incidence and prevalence of CKD might place additional strain on the current limited capacity to provide renal care worldwide (Ravani et al., 2020; Jonsson et al., 2020; Bello et al., 2017). Several studies have introduced associations between CVH and the risk of adverse outcomes by age (Hou et al., 2018; Han et al., 2016; Quach et al., 2022). However, the interaction between age and CVH using the LE8 score on CKD has not been fully explored.

Determining modifiable risk factors for CKD and ascertaining the relationship of AHA's LE8 with CKD were vital public health priorities in disease management and prevention planning, not only to illustrate the potential influence of the updated quantization algorithm of cardiovascular health on CKD but also to inform the design of public health interventions for CKD prevention. We aimed to explore the age-dependent interaction between the LE8 score and CKD among adults in the United States.