The Clinical Significance of LDL-Cholesterol on the Outcomes of Hemodialysis Patients with Acute Coronary Syndrome

Background and objectives: Dyslipidemia is one of the most important modifiable risk factors in the pathogenesis of cardiovascular disease in the general population, but its importance in the hemodialysis (HD) population is uncertain. Materials and Methods: This retrospective cohort study includes HD patients hospitalized due to acute coronary syndrome (ACS) in the period 2015-2020 with lipid profile data during ACS. A control group with preserved kidney function was matched. Risk factors for 30-day and 1-year mortality were assessed. Results: Among 349 patients included in the analysis, 246 were HD-dependent ("HD group"). HD group patients had higher prevalence of diabetes, hypertension, and heart disease than the control group. At ACS hospitalization, lipid profile and chronic statin treatment were comparable between groups. Odds ratios for 30-day mortality in HD vs. control group was 5.2 (95% CI 1.8-15; p = 0.002) and for 1-year, 3.4 (95% CI 1.9-6.1; p <0.001). LDL and LDL < 70 did not change 30-day and 1-year mortality rates in the HD group (p = 0.995, 0.823, respectively). However, survival after ACS in HD patients correlated positively with nutritional parameters such as serum albumin (r = 0.368, p < 0.001) and total cholesterol (r = 0.185, p < 0.001), and inversely with the inflammatory markers C-reactive protein (CRP; r = -0.348, p < 0.001) and neutrophils-to-lymphocytes ratio (NLR; r = -0.181, p = 0.019). Multivariate analysis demonstrated that heart failure was the only significant predictor of 1-year mortality (OR 2.8, p = 0.002). LDL < 70 mg/dL at ACS hospitalization did not predict 1-year mortality in the HD group. Conclusions: Despite comparable lipid profiles and statin treatment before and after ACS hospitalization, mortality rates were significantly higher among HD group. While malnutrition-inflammation markers were associated with survival of dialysis patients after ACS, LDL cholesterol was not. Thus, our study results emphasize that better nutritional status and less inflammation are associated with improved survival among HD patients.