Abstract
OBJECTIVE: Cardiovascular disease (CVD) is one of the leading causes of morbidity and mortality worldwide, and healthy lifestyles play a crucial role in maintaining individual cardiovascular health. Given that both CVD progression and lifestyles are dynamic in nature, assessing the association between healthy lifestyles score (HLS) and CVD risk at a single time point may have certain limitations. This study aims to identify HLS trajectories via group-based trajectory model and analyse the relationship between these trajectories and CVD risk. DESIGN: This cohort study completed the baseline survey in 2016 and conducted at least one follow-up annually from 2019 to 2024, with the first occurrence of CVD as the outcome. The epidemiological investigation included questionnaire surveys, anthropometric and physiological measurements and serum biochemistry tests. The group-based trajectory model was constructed via SAS V.9.4 PROC TRAJ and the results were visualised via R (V.4.2.2). SETTING: This study involved a rural cohort in southern Xinjiang, China. PARTICIPANT: A total of 2313 participants from four communities were included in this study, with a median (IQR) follow-up time of 6.86 (5.75-8.44) years. RESULTS: The differences in HLS across years were significant (p<0.001), whereas the differences between the CVD group and the healthy control group were significant only in 2016 (p<0.001), 2019 (p<0.001) and 2024 (p<0.001). This study identifies five distinct HLS trajectory groups (long-term low, mid-level stable increase, mid-level unstable increase, high-level decrease and ideal trajectory). Compared with the ideal trajectory group, the long-term low-level group presented the highest risk of CVD incidence (HR 6.23, 95% CI 3.38 to 11.49), followed by the mid-level unstable increase group (HR 4.14, 95% CI 2.30 to 7.45) and the mid-level stable increase group (HR 3.14, 95% CI 1.73 to 5.70). The results of stratified analysis by gender, age, hyperlipidaemia, diabetes mellitus and hypertension are consistent with the main findings. CONCLUSIONS: Distinct trajectories of HLS corresponded to differing CVD risks. Moreover, both sustained low and unstable healthy lifestyles significantly contribute to CVD risk. Therefore, the early adoption and maintenance of healthier lifestyles provide long-term benefits in reducing CVD risk.