Post-treatment level of LDL cholesterol and all-cause mortality in patients with atherosclerotic cardiovascular disease: evidence from real-world setting

This study aimed to evaluate the safety of the currently recommended target of LDL cholesterol (LDL-C) control on mortality in patients with atherosclerotic cardiovascular disease (ASCVD). Using deidentified electronic health record data, we conducted a multicentre retrospective cohort study involving individuals with documented ASCVD who had received statin treatment for at least 3 months across China. The primary outcomes assessed encompassed all-cause mortality, CV mortality, and non-CV mortality. Relationships between post-treatment LDL-C concentrations and outcomes were evaluated using restricted cubic spline curves based on Cox proportional hazards regression analyses. Additionally, competitive risk models were employed to explore associations between LDL-C levels and cause-specific mortality. Among 33 968 participants, we identified nearly linear associations of post-treatment LDL-C level with all-cause mortality and CV mortality during a median follow-up of 47 months. Notably, patients who achieved the recommended target of LDL-C (<1.4 mmol/L) were at significantly lower risks of all-cause mortality [hazard ratio (HR), 0.77; 95% confidence interval (CI), 0.69-0.86] and CV mortality (subdistribution HR, 0.68; 95% CI, 0.58-0.79), compared with those with LDL-C ≥ 3.4 mmol/L. This survival benefit was consistent in patients with different intensities of LDL-C reduction and other subgroup analyses. And no correlation was found between post-treatment LDL-C concentration and non-CV mortality. Our findings supported the safety of currently recommended target of LDL-C control and the 'lower is better' principle in patients with ASCVD.