Association of Life's Essential 8 with all-cause mortality in asthma patients: evidence from NHANES 2005-2018

Abstract

Background: Research indicates that Life's Essential 8 (LE8) has health-promoting effects for many diseases, yet few studies have explored its association with asthma patients. This research aimed to investigate the relationships between LE8 and all-cause mortality in asthma patients.

Methods: We conducted a retrospective cohort analysis of seven cycles of data from the 2005-2018 National Health and Nutrition Examination Survey (NHANES). The impact of LE8, which includes four health behaviors (diet, physical activity, smoking, and sleep) and four health factors (BMI, lipids, blood glucose, and blood pressure), on asthma mortality was analyzed using multivariate Cox proportional hazards models. Dose-response relationships between these indicators and mortality were examined using restricted cubic spline (RCS) analysis. Subgroup analyses and interaction tests were performed to verify the stability of the results.

Results: The study included 3,321 asthma patients aged 20 or older, with a median follow-up of 91.03 months, during which 331 patients died. Each one-unit increase in LE8 score was associated with a 1.4% reduction in all-cause mortality risk (HR = 0.986, 95% CI: 0.974-0.998; p < 0.001). Patients with scores ≥80 had a 58.8% lower mortality risk than those with scores <50 (HR = 0.412, 95% CI: 0.203-0.837, p = 0.014). Each one-point increase in health behavior score was linked to a 1.3% decrease in mortality risk (HR = 0.987, 95% CI: 0.982-0.992; p < 0.001). Participants with optimal health behaviors (scores ≥80) had a 53.8% lower mortality risk than those with poor scores (<50; HR = 0.462, 95% CI: 0.275-0.777; p = 0.004). RCS analysis revealed linear associations of LE8 and health behavior scores with mortality, while the relationship between health factor scores and mortality was non-linear, with mortality risk decreasing as scores increased above 80. Subgroup analyses showed stable associations between exposure variables and mortality, particularly strong protective associations in high-income groups.

Conclusion: Optimized LE8, health behavior scores, and health factor scores above 80 are associated with reduced all-cause mortality risk in asthma patients, supporting ideal cardiovascular health as an intervention strategy to lower asthma mortality.

Keywords: Life’s Essential 8; asthma; cardiovascular health; health behaviors; mortality.

Figure 1

Flowchart of the standard for participants enrolled in the study.

Figure 2

Kaplan–Meier survival analyses were used to assess the associations between LE8 score (A), health behavior score (B), health factor score (C), and all-cause mortality in asthma patients. LE8: Life’s Essential 8.

Figure 3

Cox regression using restricted cubic spline regression of LE8 score (A), health behavior score (B), health factor score (C), with all-cause mortality. LE8: Life’s Essential 8. (A) was adjusted for gender, age, race, education, marriage, poverty income ratio, alcohol consumption, chronic bronchitis, emphysema, cancer, white blood cells, cardiovascular disease, and glomerular filtration rate. (B) was further adjusted for health factor score. (C) was further adjusted for health behavior score.

Figure 4

Subgroup analysis between Life’s Essential 8 score with all-cause mortality in patients of asthma, weighted. Adjusted by gender, age, race, education, marriage, poverty income ratio, alcohol consumption, chronic bronchitis, emphysema, cancer, white blood cells, cardiovascular disease, and glomerular filtration rate except for the stratification variable. Abbreviations: HR, hazard ratios; 95% CI, 95% confidence interval; PIR, poverty income ratio; CVD, Cardiovascular disease.