Frailty, an age-related syndrome marked by a decline in homeostatic reserve and heightened vulnerability to stressors, is prevalent among older people (1). It was estimated by a meta-analysis that the incidence of frailty was 43.4 new cases per 1,000 person-years (2). As the aging population rapidly expands, the prevalence of frailty among older adults worldwide is increasing dramatically (3). Frailty increases the risk of various adverse health outcomes, including impaired mobility, falls, hospitalizations, and mortality (4). Consequently, elucidating the underlying causes of frailty is essential for developing effective preventive strategies to reduce its prevalence and alleviate the burden on primary healthcare.

In 2022, the American Heart Association (AHA) updated the operational tool for cardiovascular health (CVH) assessment, known as Life’s Essential 8 (LE8), to address existing cardiovascular disease (CVD) and related risk factors, thereby promoting the health of both populations and individuals (5). The LE8 score has been well validated as a composite and quantified measurement of CVH (6) and has demonstrated inverse associations with adverse outcomes, such as diabetes, sarcopenia, dementia, and all-cause and CVD mortality (7–10). Chronic conditions, such as CVD (including atrial fibrillation, heart failure, and coronary heart disease), are more likely to contribute to the incidence of frailty (11). Several of the LE8 metrics, including physical inactivity, unhealthy dietary habits, insufficient sleep, lipid abnormalities, and glucose metabolism disorders, are known to contribute to a state of chronic low-grade inflammation and metabolic dysregulation (12–15). These processes promote the release of pro-inflammatory factors, which are implicated in both cardiovascular risk and the pathogenesis of frailty. By reducing physiological reserve capacity and promoting endothelial dysfunction and atherosclerosis, these mechanisms impair the body’s ability to cope with stressors, thereby contributing to the onset of frailty (16). Therefore, managing and improving CVH through the LE8 metrics is hypothesized to mitigate these inflammatory and metabolic pathways, offering a preventive strategy against frailty. One previous study examined the cross-sectional association between LE8 and frailty among American cancer survivors (17). However, the evidence on the association between LE8 and frailty in the community-dwelling older adults is still lacking, and it remains unclear whether the LE8 score impacts the incidence of frailty.

We hypothesized that a higher LE8 score, reflecting better CVH, would be significantly associated with lower odds of frailty at baseline and reduce the risk of frailty incidence during follow-up. In this study, we aim to investigate both the cross-sectional and longitudinal associations between the LE8 score and frailty among community-dwelling older adults. Understanding these associations helps provide population-based evidence supporting the role of CVH maintenance in preventing frailty in older adults.

In this large, extensive community-based study, we examined the cross-sectional and longitudinal associations between the LE8 score and frailty among older adults. Our findings revealed a significant inverse relationship between LE8 score and frailty in older women and men. Furthermore, a dose–response relationship was also identified between the LE8 score and frailty. We not only observed a significantly negative cross-sectional association between the LE8 score and frailty but also observed that a higher LE8 score was significantly associated with a lower risk of frailty. Our study will provide scientific evidence supporting the importance of CVH management in preventing frailty.

LE8, as a novel assessment tool for CVH status, has been demonstrated to be associated with reduced risks of diabetes mellitus in Chinese adults, as well as non-alcoholic fatty liver disease and hypertension in US adults (25–27). Previous studies reported that a 1-unit increment in the combined lifestyle factors (physical activity, dietary quality, and smoking) was associated with lower frailty (β: −0.62, 95% CI: −0.84, −0.53) (28). Some metrics included in the LE8 have also been associated with a lower risk of frailty, such as healthy dietary habits, an appropriate BMI, recommended physical activity, and not smoking (29–32). In addition to lifestyle-related assessments, the LE8 also includes metabolic-related assessments, which provide a more comprehensive representation of overall CVH. A cross-sectional analysis involving 2,542 cancer survivors enrolled in the National Health and Nutrition Examination Surveys revealed that each unit increase in the LE8 score was associated with a 5% reduction in the odds of frailty (OR: 0.95, 95% CI: 0.94, 0.96) (17). Similarly, our study observed this cross-sectional association and, for the first time, presents a dose–response association between the LE8 score and frailty in the community-dwelling older adults.

Interestingly, our RCS analysis in the cross-sectional data revealed a significant non-linear association between LE8 score and frailty. The curve suggested a steep decline in frailty risk as the LE8 score increased from lower to moderate levels, followed by a gradual flattening at higher LE8 scores. This finding implies a potential saturation effect, where initial improvements in CVH yield substantial benefits for frailty prevention, but additional gains beyond a certain level may provide diminishing returns. Such a pattern may reflect biological homeostasis in cardiovascular and metabolic systems, in which moderate enhancement in behaviors (e.g., physical activity, diet, and smoking cessation) and clinical factors (e.g., blood pressure and glucose) markedly reduce systemic inflammation and oxidative stress, whereas further optimization exerts relatively limited additional protection (33). In contrast, the longitudinal analysis showed a linear inverse relationship, indicating a consistent reduction in frailty incidence with increasing LE8 score during follow-up. Collectively, these findings imply that maintaining better CVH exerts protective effects against frailty, with the most pronounced benefit observed among individuals with poor or intermediate LE8 scores.

Our result aligns with previous cross-sectional evidence supporting an inverse curvilinear trend for the association between the LE8 score and depression, cognitive function, and metabolic syndrome, suggesting that lower CVH is associated with a higher adverse outcome compared to higher CVH (34–36). A prospective cohort study including 19,951 US adults aged 30–79 years identified approximately linear dose–response associations of increased total CVH metric score with reduced risk of all-cause and CVD-specific mortality (37). Our findings have important public health implications for China’s community-based healthcare system. Integrating the LE8 evaluation into these existing health checks could provide a simple, standardized, and actionable metric for monitoring CVH and identifying older adults at risk of frailty. This approach would allow community healthcare workers to deliver targeted lifestyle interventions—such as smoking cessation, dietary guidance, and physical activity promotion—within routine healthcare services. Furthermore, tracking the LE8 score over time could help evaluate the effectiveness of primary prevention programs and guide resource allocation for healthy aging initiatives.

The association between LE8 and frailty incidence is biologically plausible. LE8 incorporates factors such as unhealthy dietary habits, obesity, insufficient sleep, lipid abnormalities, and glucose metabolism disorders, all of which are associated with an increased release of pro-inflammatory factors (38–42). These pro-inflammatory markers include C-reactive protein, interleukin-6, and tumor necrosis factor-alpha, which have been observed in individuals with frailty and are known contributors to cardiovascular risk (16). These factors can reduce physiological reserve capacity and lead to dysregulation of various physiological systems, contributing to an imbalance that negatively affects overall health (43). In addition, inflammatory factors adversely affect CVH by promoting endothelial dysfunction and atherosclerosis while further reducing physiological reserve capacity and impairing stress response capabilities, contributing to the onset of frailty (44). By improving CVH through lifestyle modifications, LE8 may help mitigate the inflammatory processes that contribute to frailty.

An important consideration in examining the LE8 score and its association with frailty risk is the need to comprehensively account for lifestyle differences between sexes. Our baseline characteristics of participants align with findings from previous studies, which indicated that women tend to have higher LE8 scores than men (45, 46). Consequently, we analyzed the quartiles of the LE8 score separately by sex and adjusted for sex in subsequent models. Additionally, we stratified our analyses by sex and found consistent results across both groups. Collectively, these findings suggest that improving the LE8 score may reduce frailty risk irrespective of sex and serve as a useful screening tool to identify older adults at high risk for frailty, facilitating targeted frailty prevention and treatment strategies.

The strengths of this study included the large sample size and the longitudinal study design. We also fitted Cox proportional hazards models using the ICPHREG procedure in SAS, which specializes in analyzing interval-censored data. However, several limitations should be noted. First, since our study used self-reported information such as physical activity, smoking, and other variables to create the LE8 score and FI, classification errors or recall bias can occur when participants respond to the questionnaire. However, the self-report questionnaire used for assessing frailty has been validated (47). Second, due to limited data on more specific dietary factors in our study, we could not calculate the overall dietary quality score. Third, our participants were drawn from only one administrative district in Shenzhen, which could limit the generalizability of our findings. Nevertheless, it is well known that Shenzhen has the largest migrant population in China. Therefore, the results may be reliable and stable. Finally, some unmeasured factors, such as duration of residence and social support, may contribute to residual confounding.

In this longitudinal study of community-dwelling older adults, we found that a higher LE8 score was consistently and significantly associated with both a lower prevalence of frailty and a reduced risk of incident frailty. These findings underscore the critical importance of maintaining optimal CVH for frailty prevention. The interventions focused on improving LE8 components (e.g., diet, physical activity, sleep, and blood pressure) may serve as an integrated and highly effective primary prevention strategy against frailty. Future research is needed to explore the causal relationship between LE8 score and frailty incidence.