Non-high-density lipoprotein cholesterol and mortality among peritoneal dialysis patients

The non-high-density lipoprotein cholesterol to high-density lipoprotein cholesterol ratio and its combination with obesity indicators as a predictor of all cause and cardiovascular mortality in non-diabetic individuals

BACKGROUND

The non-high-density lipoprotein cholesterol to high-density lipoprotein cholesterol ratio (NHHR) represents a novel composite lipid marker for atherosclerosis and cardiovascular disease (CVD). Nevertheless, the correlation between NHHR and mortality in the non-diabetic population remains indistinct.

METHODS

This study included 20,774 non-diabetic individuals from the 1999-2018 National Health and Nutrition Examination Survey (NHANES). We employed a weighted multivariate Cox proportional hazards model and restricted cubic splines to assess the associations between NHHR, its combination with obesity indicators, and all-cause and CVD mortality.

RESULTS

During a mean follow-up period of 62 months, a total of 897 participant deaths were recorded, of which 155 were attributed to cardiovascular causes. The restricted cubic splines revealed a U-shaped association between NHHR and all-cause mortality, while an L-shaped association was observed for CVD mortality. The analysis of threshold efects revealed that the infection points for NHHR and all-cause and CVD mortality were 2.65 and 2.07, respectively. The cubic spline revealed a nonlinear correlation was observed between NHHR-BMI, NHHR-WC and NHHR-WHtR and all-cause and CVD mortality.

CONCLUSION

NHHR and its combination with obesity indicators can be a meaningful predictor of all-cause mortality and CVD mortality in non-diabetic individuals.

Lipid and immunophenotypic profiles in hemodialysis patients with citrate vs. acetate dialysates

Background

Chronic kidney disease (CKD) is a significant cardiovascular (CV) risk factor, with dialysis-dependent CKD (DD-CKD) patients facing high mortality rates. Hypercholesterolemia is another crucial CV risk factor, typically managed with lipid-lowering therapy, though its efficacy in DD-CKD remains uncertain. Evidence shows mixed results regarding the benefits of statins in these patients. Citrate-based dialysates are known to reduce inflammatory biomarkers compared to acetate-based ones, potentially impacting lipid profiles and immune responses. This study aimed to determine the effects of citrate vs. acetate dialysate on lipid profiles and immunophenotypes in DD-CKD patients.

Methods

This unicentric, cross-over, prospective study included 21 hemodialysis patients (10 males, 11 females, average age 62.25 years). Each patient underwent 24 dialysis sessions (12 with each dialysate) and acted as their own control. Lipid profiles, immunological parameters, and nutritional and inflammatory markers were measured before the last session with each dialysate.

Results

After twelve dialysis sessions with citrate dialysate (CD), compared to acetate dialysate (AD), there was a statistically significant decline in TG and remnant cholesterol, with a decrease in HDL and an increase in LDL. Regarding immunology, C3 complement levels were higher, while CD3+ CD8+ and CD16+ 56+ lymphocytes were lower. Finally, total lymphocytes were lower with AD than with CD. We found no difference in predialysis nutritional nor inflammatory parameters except for ESR, which was higher when subjects used CD than AD.

Conclusion

There are significant differences in lipid and immunophenotypic profiles with CD in comparison to AD. Interestingly, there could be an advantageous profile given the reduced amount of remnant cholesterol and TG. However, further studies are needed to understand if the observed changes lead to beneficial hard clinical outcomes in DD-CKD patients.

Dose-response relationship between lipids and all-cause mortality in the dialysis population: a meta-analysis

BACKGROUND

The use of lipid-lowering drugs in the dialysis population has been controversial and there is no target for the dialysis population.

OBJECTIVES

To elucidate the dose-response relationship between lipids and all-cause mortality in the dialysis population.

METHODS

Computer searches of PubMed, Embase, Web of Science, CNKI, and Wanfang. Data were conducted to collect published cohort studies on lipids and all-cause mortality in the dialysis population from home and abroad up to February 2023. Meta-analysis was applied to calculate the combined effect size (Hazard ratio) and its 95% confidence interval and dose-response relationship by applying Stata17.0.

RESULTS

A total of 11 publications with a cumulative total of 106,808 individuals were included. All-cause mortality was statistically different between the highest dose total cholesterol (TC) group and the low TC group (HR = 0.82, 95% CI = 0.75-0.90, P < 0.05). The TC range for lower all-cause mortality is > 140.5 mg/dL, and on this basis, TC in the range of 180-220 mg/dL may have a better prognosis for dialysis population. There was a nonlinear relationship between Non-high-density lipoprotein cholesterol (NHDL-C) cholesterol and all-cause mortality, with no statistical difference between the high and low dose group. In contrast, Low-density lipoprotein cholesterol (LDL-C) masked its association with all-cause mortality due to changes in death spectrum, differences in relative time risks, and other factors. In the 50-450 mg/dL range, all-cause mortality in the dialysis population was positively associated with triglycerides (TG), with a 2.5% increase in all-cause mortality per 50 mg/dL increase in TG (HR = 1.025, 95% CI = 1.003-1.048, P = 0.01).

CONCLUSION

TC is a target for monitoring the dialysis population, which has the lowest all-cause mortality in the range of 180-220 mg/dL. However, NHDL-C and LDL-C monitoring is not clinically meaningful. Increased TG can contribute to the risk of higher all-cause mortality in dialysis patients.

Association of albumin to non-high-density lipoprotein cholesterol ratio with mortality in peritoneal dialysis patients

OBJECTIVE

Malnutrition and inflammation are associated with mortality in peritoneal dialysis (PD) patients. Serum albumin and non-high-density lipoprotein cholesterol (non-HDL-C) are independently associated with mortality in PD patients. Combining albumin and non-HDL-C with mortality may be more plausible in clinical practice.

METHODS

This retrospective cohort study included 1954 Chinese PD patients from 1 January 2009 to 31 December 2016. Kaplan-Meier curve was used to determine the relationship between albumin to non-HDL-C ratio and all-cause mortality. Cox regression analysis was applied to assess the independent predictive value while adjusting for confounding factors. Competitive risk analysis was used to examine the effects of other outcomes on all-cause mortality prognosis.

RESULTS

In the 33-month follow-up period, there were 538 all-cause deaths. Kaplan-Meier analysis presented significant differences in all-cause mortality. Multivariate Cox regression showed that the risk of all-cause mortality was lower in the moderate group (9.36-12.79) (HR, 0.731; 95% CI, 0.593-0.902, p = 0.004) and the highest group (>12.79) (HR, 0.705; 95% CI, 0.565-0.879, p = 0.002) compared to the lowest group (≤9.36). Competitive risk analysis revealed significant differences for all-cause mortality (p < 0.001), while there was no statistical significance for other competing events.

CONCLUSIONS

Low albumin to non-HDL-C ratio was associated with a high risk of all-cause mortality in PD patients. It may serve as a potential prognostic biomarker in PD patients.

Longer serum phosphorus time in range associated with lower mortality risk among peritoneal dialysis patients: a multicenter retrospective cohort study

BACKGROUND

Relationship between serum phosphorus time in range and mortality risk in peritoneal dialysis (PD) patients remains uncertain. We aimed to evaluate the association between serum phosphorus time in range and all-cause mortality in Chinese PD population.

METHODS

This was a multicenter, retrospective, cohort study of 1,915 patients collected from January 2008 to October 2020 in 4 Chinese centers. Serum phosphorus time in range was estimated as the months during the first year that a patient's serum phosphorus level was within the target range (defined as 1.13-1.78 mmol/L). The primary outcome was all-cause mortality. The secondary outcomes were cardiovascular (CV) mortality and PD withdrawal. Cox proportional hazards regression model with comprehensive adjustments was used to assess the association.

RESULTS

The primary outcome occurred in 249 (13.0%) PD patients over a median follow-up of 28 months. Overall, the serum phosphorus time in range was negatively associated with all-cause mortality (per 3-month increments, adjusted HR [aHR], 0.83; 95%CI: 0.75-0.92), CV mortality (per 3-month increments, aHR, 0.87; 95%CI: 0.77-0.99), and PD withdrawal (per 3-month increments, aHR, 0.89; 95%CI: 0.83-0.95). Competing-risk model showed that the relationship of serum phosphorus time in range with all-cause mortality remained stable. None of the variables including demographics, history of diabetes and CV disease, as well as several PD-related and clinical indicators modified this association.

CONCLUSIONS

PD patients with longer serum phosphorus time in range in the first year was negatively associated with all-cause mortality and CV mortality. Our findings highlight the importance of maintaining serum phosphorus levels within 1.13-1.78 mmol/L for PD patients.

Remnant cholesterol predicts cardiovascular mortality beyond low-density lipoprotein cholesterol in patients with peritoneal dialysis

BACKGROUND

Patients undergoing peritoneal dialysis (PD) are prone to dyslipidemia. However, studies concerning remnant cholesterol (RC) in such patients are limited.

OBJECTIVE

We aimed to investigate the association between RC and cardiovascular (CV) mortality in patients on PD.

METHODS

Patients who initiated PD at our center (2006-2018) were retrospectively enrolled. Adjusted Cox models were used to evaluate the independent association between baseline RC levels and CV mortality. We classified patients into 4 concordant/discordant categories according to their baseline lipid profiles. Cox models were then used to determine the association between different low-density lipoprotein cholesterol (LDL-C) and RC levels and CV mortality risk.

RESULTS

The study enrolled 2333 individuals, with a mean RC of 33.4 mg/dL. RC levels were positively associated with CV mortality risk independent of LDL-C in patients on PD (hazard ratio [HR]: 1.05; 95% confidence interval [CI]: 1. 00-1.10). In the concordant/discordant categories, patients with high LDL-C and RC levels had a higher CV mortality risk (HR: 1.52; 95% CI: 1.01-2.28) than those with low LDL-C and RC levels in the entire cohort. Moreover, in older patients, a higher RC level increased CV mortality risk regardless of the LDL-C level (HR: 2.41, 95% CI: 1.22-4.74; HR: 2.15, 95% CI: 1.12-4.14).

CONCLUSIONS

RC levels are elevated in patients on PD and can predict CV mortality beyond LDL-C levels. RC levels should be considered alongside LDL-C levels when assessing prognostic lipid levels in these patients. More attention should be given to RC than to LDL-C in older patients undergoing PD.

Association of Ratio of Apolipoprotein B to Apolipoprotein A1 With Survival in Peritoneal Dialysis

Background

Although the ratio of apolipoprotein B (apo B) to apolipoprotein A1 (apo A1) (apo B/apo A1) seems to be associated with mortality in hemodialysis (HD) patients, the association of apo B/apo A1 ratio with death remains not clear in peritoneal dialysis (PD) patients.

Aims

The study targets to examine the relationship of apo B/apo A1 ratio with survival in patients receiving PD treatment.

Methods

In this single-center prospective observational cohort study, we enrolled 1,616 patients receiving PD treatment with a median follow-up time of 47.6 months. We used a multivariable Cox proportional hazards model to examine the relationship between apo B/apo A1 ratio and cardiovascular (CV) and all-cause mortality. The association of apo B/apo A1 ratio with atherosclerotic and non-atherosclerotic CV mortality was further evaluated by competing risk regression models.

Results

During the follow-up, 508 (31.4%) patients died, 249 (49.0%) died from CV events, of which 149 (59.8%) were atherosclerotic CV mortality. In multivariable models, for 1-SD increase in apo B/apo A1 ratio level, the adjusted hazard ratios for CV and all-cause mortality were 1.26 [95% confidence interval (CI), 1.07–1.47; P = 0.005] and 1.20 (95% CI, 1.07–1.35; P = 0.003), respectively. The adjusted subdistribution hazard ratios for atherosclerotic and non-atherosclerotic CV mortality were 1.43 (95% CI, 1.19–1.73; P &lt; 0.001) and 0.85 (95% CI, 0.64–1.13; P = 0.256), respectively. For quartile analysis, patients in quartile 4 had higher CV, all-cause, and atherosclerotic CV mortality compared with those in quartile 1. Moreover, apo B/apo A1 ratio had a diabetes-related difference in CV, all-cause, and atherosclerotic CV mortality.

Conclusion

Elevated apo B/apo A1 ratio level was significantly associated with CV, all-cause, and atherosclerotic CV mortality in patients undergoing PD. Moreover, the association was especially statistically significant in patients with diabetes.