Lower LDL-C levels associated with increased all-cause mortality among high-risk hemodialysis patients

Over years studies have demonstrated that reducing low-density lipoprotein cholesterol (LDL-C) can effectively decrease the risks associated with kidney related diseases, coronary artery disease, revascularization, and ischemic stroke.

In a recent study conducted in South Korea reveals that in older hemodialysis patients who had not previously received dyslipidemia treatment or elevated LDL-C levels showed no association with increased all-cause mortality. Intriguingly, lower LDL-C levels appeared to be associated with an unfavorable effect on all-cause mortality among high-risk hemodialysis patients. The findings of the study are published in BMC Nephrology.

Researchers enrolled a total of 2,732 incident hemodialysis patients aged > 70 years from a retrospective cohort of the Korean Society of Geriatric Nephrology from 2010 Jan to 2017 Dec, which included 17 academic hospitals in South Korea. Of these patients, 1,709 were statin-naïve, and 1,014 were analyzed after excluding those with missing LDL-C level data. We used multivariate Cox regression analysis to select risk factors from 20 clinical variables among the LDL-C groups.

The findings of the study are

• The mean age of the entire patient population was 78 years, with no significant differences in age between quartiles Q1 to Q4.

• However, the proportion of males decreased as the quartiles progressed towards Q4 (p < 0.001). The multivariate Cox regression analysis, which included all participants, showed that low LDL-C levels were associated with all-cause mortality.

• In the final model, compared to Q1, the hazard ratios (95% confidence interval) were 0.77 (0.620–0.972; p = 0.027), 0.85 (0.676–1.069; p = 0.166), and 0.65 (0.519–0.824; p < 0.001) for Q2, Q3, and Q4, respectively, after adjusting for covariates, such as conventional and age-specific risk factors.

• The final model demonstrated that all-cause mortality increased as LDL-C levels decreased, as confirmed by a restrictive cubic spline plot.

Researchers concluded that “In older hemodialysis patients who had not previously received dyslipidemia treatment, elevated LDL-C levels were not associated with increased all-cause mortality. Intriguingly, lower LDL-C levels appear to be associated with an unfavorable effect on all-cause mortality among high-risk hemodialysis patients.”

Reference: Song, J.H., Park, E.H., Bae, J. et al. Effect of low-density lipoprotein level and mortality in older incident statin-naïve hemodialysis patients. BMC Nephrol 24, 289 (2023). https://doi.org/10.1186/s12882-023-03337-5.