The Relationship Between C-reactive Protein To High-density Lipoprotein Cholesterol Ratio And Prognosis In Patients On Peritoneal Dialysis

Objectives:High-density lipoprotein cholesterol(HDL-C)is closely related to cardiovascular events and death risk in the general population.However,for patients with end-stage renal disease(ESRD),the correlation between HDL-C and prognosis is controversial.C-reactive protein(CRP)is a common indicator reflecting the inflammatory state of patients.At present,some studies have confirmed that the prediction of HDL-C on the prognosis of patients is affected by CRP,and tried to explore the relationship between the ratio of CRP to HDL-C and the prognosis of patients.However,there are no relevant studies in peritoneal dialysis(PD)patients.The purpose of this study was to explore the correlation between CRP to HDL-C Ratio(CHR)and all-cause death in patients with PD.Methods:This is a single-center,retrospective study.The patients who received peritoneal dialysis catheterization at the peritoneal dialysis center of Shengjing Hospital of China Medical University from January 1,2012 to December 31,2020,and maintain peritoneal dialysis for at least 3 months and follow up regularly were enrolled in the study.The primary end point was all-cause death.First,the patients were divided into two groups according to the HDL-C level by X-tile including low HDL-C group(≤1.10mmol/L)and high HDL-C group(>1.10 mmol/L).The baseline levels of clinical data of the two groups were compared.The correlation between HDL-C and all-cause death of patients was initially evaluated in the whole population by Cox proportional risk regression model,and the impact of CRP on the correlation between HDL-C and prognosis was further analyzed in the subgroups with CRP≥6 mg/L and CRP<6 mg/L.Secondly,according to the CHR level,the patients were divided into three groups by X-tile,including low CHR group(≤2.847),medium CHR group(2.847-5.662)and high CHR group(>5.662).The baseline level of clinical data of the three groups was compared.The survival analysis was performed by Kaplan-Meier method and Log-rank test.The correlation between CHR and all-cause death was analyzed by Cox proportional risk regression model.In addition,subgroup analysis and interaction analysis was used to further evaluate the predictive value of CHR on the prognosis of patients in different subgroups.Results:Among 349 patients with PD,283 were finally included,with an average starting PD age of(51.01 ± 15.96)years.Among them,152 were male patients(53.7%),and the median follow-up time was 26(13,43)months.There was no statistically significant difference in the risk of all-cause death between patients with high HDL-C and patients with low HDL-C in the overall population(HR,0.592;95% CI,0.349-1.004;P=0.052),but subgroup analysis showed that the risk of all-cause death of patients with high HDL-C was reduced in patients with CRP ≤ 6mg/L,with a statistically significant difference(HR,0.397;95% CI,0.180-0.874;P=0.022),After multivariate Cox analysis,this correlation still exists(HR,0.309;95% CI,0.110-0.863;P=0.025),but there is no correlation between them in patients with CRP>6mg/L.To further analyze the predictive value of CHR on the prognosis of PD patients,the patients were divided into three groups according to the level of CHR: 94 patients in the low CHR group(≤ 2.847),72 patients in the middle CHR group(2.847-5.662),and 117 patients in the high CHR group(>5.662).There were significant differences in age,low-density lipoprotein cholesterol sex,Body Mass Idex(BMI),cardiovascular disease(CVD)history,Estimated Glomerular Filtration Rate(e GFR),hemoglobin,serum albumin,CRP,triglyceride and(LDL-C)among the three groups(P<0.05).During the follow-up,a total of 78 patients died,including 13 in the low CHR group,16 in the middle CHR group,and 49 in the high CHR group.Kaplan-Meier survival curve showed that the survival rate of low CHR group was significantly higher than that of high CHR group(Log-rank P<0.001).After incorporating CHR and other variables into the multivariate Cox proportional risk model,it was found that the all-cause mortality risk of patients with high CHR was 2.304 times higher than that of patients with low CHR(HR,2.304;95% CI,1.102-4.816;P=0.026).In subgroup analysis,the impact of different parameters,including gender,age,BMI,diabetes history,cardiovascular disease history,and the use of lipid-lowering drugs,on the correlation between CHR and all-cause death of patients was evaluated,suggesting that in most subgroups of patients,a positive correlation between CHR and all-cause death can still be observed,while interaction analysis suggested that the various parameters evaluated did not significantly change the correlation between CHR and all-cause death.Conclusions: The correlation between HDL-C and all-cause death in patients with PD is also affected by CRP levels.CHR is an independent risk factor for all-cause death in PD patients and can be used as an effective indicator to evaluate the prognosis of patients with PD.