Association between serum lipids, polyunsaturated fatty acids, and prognosis in maintenance hemodialysis patients

Risks of mortality and cardiovascular disease (CVD) are significantly higher in hemodialysis (HD) patients than in the general population, where dyslipidemia is an established risk factor for CVD and mortality. There is no clear conclusion, however, whether dyslipidemia is a significant risk factor for CVD and mortality in HD patients. Similarly, the association between the polyunsaturated fatty acids (PUFAs) and the mortality is not clear in HD patients.

We retrospectively investigated mortality and CVD events in 420 HD patients. We classified patients into high- and low-lipid groups depending on their lipid levels. Survival rates were calculated using the Kaplan-Meier analysis and evaluated by the log-rank test. The risk estimates were computed using a multivariate Cox proportional hazard analysis.

During their follow-up (June 2011 to June 2016), 151 patients died (37 of CVD), and 112 patients experienced new CVD events. On Kaplan-Meier analysis, the number of all-cause deaths and CVD events were significantly higher in the low HDL-cholesterol group (P < 0.01, log-rank test). Similarly, the number of all-cause deaths was significantly higher in the high eicosapentaenoic acid/arachidonic acid ratio group (P < 0.01, log-rank test). Multivariate Cox proportional analysis showed that HDL-cholesterol was a significant prognostic indicator for new onset of CVD events (low: 0, high: 1, hazard ratio 0.66, 95% confidence interval 0.44-0.97; P = 0.04).

In HD patients, LDL-cholesterol and non-HDL-cholesterol levels are not associated with mortality or CVD events. The HDL-cholesterol level, however, is an independent predictor of new CVD events even in HD patients.