[Mediating effects of cardiovascular health status in association between educational level and cardiovascular...

Objective: To analyze the mediating effect of cardiovascular health status (CVH) on the association between educational level and cardiovascular disease (CVD). Methods: The participants were from Shanghai Suburban Adult Cohort and Biobank, and questionnaire survey, physical examination, blood biochemistry were conducted from 2016 to 2020 for baseline information collection, and follow up was conducted until March 31, 2024 based on the medical data, CVD incidence data and death surveillance data at different levels. The associations of educational level, CVH and time to CVD onset of the study population were analyzed using the accelerated failure time model to analyze the mediating effects of CVH, health behaviors, and health factors in the association of educational level and time to CVD onset. The mediating effects of educational level, gender, and age moderated associations were also analyzed. Results: A total of 57 312 participants were included, with 2 780 new cases of CVD during a median follow-up of 6.71 (6.71-6.72) years, and a mean incidence density of 7.77/1 000 person-years (95%CI: 7.48/1 000 person-years -8.06/1 000 person-years). In total, the less educational level and the lower CVH, the higher CVD incidence density (P<0.05). The results of accelerated failure time models showed that the time ratio for CVD-free survival was 1.15 (95%CI: 1.06-1.24) and 1.33 (95%CI: 1.10-1.60) for moderate and high educational level, respectively. The results of the mediation effect analysis showed that the association between moderate and high educational level and time to CVD onset was 29.60% (20.50%-50.00%) and 36.10% (23.80%-59.00%), 9.97% (5.07%-20.00%) and 13.84% (6.84%-29.00%), 15.24% (9.64%-27.00%) and 17.55% (11.58%-33.00%) of mediators mediated by CVH, health behaviors, health factors, respectively. Among them, there was an exposure-mediated interaction of educational level and a positive moderating effect of age. Conclusion: CVH, health behaviors and health factors had a proportionate mediating effect in the association between educational level and risk of CVD development.