Association between LDL-C/HDL-C ratio and long-term carotid plaque risk in middle-aged and elderly rural populations: a prospective population study.

Background: Atherosclerotic cardiovascular and cerebrovascular diseases are still the main cause of global incidence rate and mortality. The LDL-C/HDL-C ratio (LHR) has been identified as a potential biomarker for cardiovascular risk. However, the relationship between it and the long-term risk of carotid plaques is not yet clear, especially in low-income populations in China. Methods: This prospective cohort study included adults aged ≥45 years without carotid plaque at baseline from low-income rural areas of Tianjin, China. Baseline characteristics were collected in 2014, and follow-up data were obtained in 2019. The primary outcome was the development of new carotid plaques, assessed using carotid ultrasound. The relationship between the LDL-C/HDL-C ratio (LHR) and new carotid plaques was analyzed using multifactorial logistic regression, with the presence or absence of new-onset plaques as the dependent variable. Additionally, we utilized restricted cubic spline (RCS) regression to visually present the potential nonlinear relationship between LHR and the risk of carotid plaque. Results: Over the six-year follow-up period, 606 participants (38.3%) developed new carotid plaques. Higher LHR was significantly associated with an increased risk of new carotid plaques, with each unit increase in LHR corresponding to a 35.9% higher risk (OR = 1.359, 95% CI: 1.180-1.566, Conclusion: The research results indicate that there is a non-linear positive correlation between LHR and the long-term risk of carotid plaques in middle-aged and elderly populations, suggesting that LHR may be an effective indicator for screening carotid plaques in grassroots middle-aged and elderly populations.