Inflammatory markers as mortality predictors in continuous ambulatory peritoneal dialysis patients

Serum amyloid A and risks of all-cause and cardiovascular mortality in chronic kidney disease: a systematic review and dose-response meta-analysis

BACKGROUNDS

The available literature on the correlation between serum amyloid A (SAA) and prognosis of chronic kidney disease (CKD) are limited, and the findings from existing studies are inconclusive. This meta-analysis aimed to evaluate the available evidence regarding the link between SAA and risks of all-cause and cardiovascular mortality in CKD patients. Additionally, we aimed to investigate the potential dose-response relationships, provided that adequate data is accessible.

METHODS

Pubmed and Embase were searched for related literature (last update: 12 July 2023). The pooled effect estimates were calculated using random- or fixed-effects models depending on heterogeneity among studies.

RESULTS

This meta-analysis incorporated 8 studies encompassing 2331 CKD patients. The findings revealed an 85% increase in all-cause mortality risk [hazard risk (HR) 1.85, 95% confidence interval (CI) 1.29-2.65] and a 39% increase in cardiovascular mortality risk (HR 1.07, 95% CI 1.07-1.80) when comparing the highest tertile of baseline SAA levels to the lowest tertile. Furthermore, a positive linear relationship between SAA and all-cause mortality risk was observed (Pnon-linearity = 0.959), with a 17.7% increase in risk for each 10 mg/L SAA increase (HR 1.177, 95% CI 1.055-1.313). Similarly, a linear relationship between SAA and cardiovascular mortality risk was identified (Pnon-linearity = 0.477) with a 19.3% increase in risk for each 10 mg/L SAA increase (HR 1.193, 95% CI 1.025-1.388).

CONCLUSIONS

This meta-analysis provided evidence that SAA levels are positively and linearly associated with risks of all-cause and cardiovascular mortality among CKD patients.

Use of the systemic inflammation response index (SIRI) as a novel prognostic marker for patients on peritoneal dialysis

BACKGROUND

The systemic inflammatory response index (SIRI), a novel inflammation maker, has proven to be associated with prognostic outcomes in various diseases. However, few studies have been conducted assessing how SIRI may influence outcomes of patients on peritoneal dialysis (PD). Herein, we assessed the predictive value of SIRI on mortality all-cause mortality, including cardiovascular disease (CVD) in PD patients.

METHODS

A total of 646 PD patients were enrolled in this study. PD patients received regular PD treatments at the Zhujiang Hospital from 1 January 2011 to 31 December 2018. SIRI values could be computed as follows: neutrophil count × monocyte count/lymphocyte count. Patients were divided into two groups according to the median level of SIRI. Cox regression analysis and Kaplan-Meier methods were applied to analyze the relationship between SIRI and mortality outcomes in PD patients.

RESULTS

During the median 31-month follow-up period, 97 (15.0%) PD patients died from all-causes, and 47 (49.0%) died of CVD. Kaplan-Meier analyses revealed that a high SIRI corresponded to the high mortality of all-cause deaths, including CVD (both p < 0.001) in patients on PD. After adjusting for potential confounders, the higher SIRI level was significantly associated with an increased all-cause mortality (HR: 2.007, 95% CI: 1.304-3.088, p = 0.002) and cardiovascular mortality (HR: 2.847, 95% CI: 1.445-5.608, p = 0.002).

CONCLUSIONS

SIRI was a promising predictor of mortality in PD patients, with a higher SIRI corresponding to increased risk of mortality.

Plasma fibrinogen and mortality in patients undergoing peritoneal dialysis: a prospective cohort study

BACKGROUND

Plasma fibrinogen is significantly associated with cardiovascular (CV) events and mortality in the general population. However, the association between plasma fibrinogen and mortality in patients undergoing peritoneal dialysis (PD) is unclear.

METHODS

This was a prospective cohort study. A total of 1603 incident PD patients from a single center in South China were followed for a median of 46.7 months. A Cox regression analysis was used to evaluate the independent association of plasma fibrinogen with CV and all-cause mortality. Models were adjusted for age, sex, smoking, a history of CV events, diabetes, body mass index, systolic blood pressure, hemoglobin, blood platelet count, serum potassium, serum albumin, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, hypersensitive C-reactive protein, estimated glomerular filtration rate, antiplatelet agents and lipid-lowering drugs.

RESULTS

The mean age was 47.4 ± 15.3 years, 955 (59.6%) patients were male, 319 (19.9%) had a history of CV events, and 410 (25.6%) had diabetes. The average plasma fibrinogen level was 4.12 ± 1.38 g/L. Of the 474 (29.6%) patients who died during follow-up, 235 (49.6%) died due to CV events. In multivariable models, the adjusted hazard ratios (HRs) for quartile 1, quartile 3, and quartile 4 versus quartile 2 were 1.18 (95% confidence interval [CI], 0.72-1.95, P = 0.51), 1.47 (95% CI, 0.93-2.33, P = 0.10), and 1.78 (95% CI, 1.15-2.77, P = 0.01) for CV mortality and 1.20 (95% CI, 0.86-1.68, P = 0.28), 1.29 (95% CI, 0.93-1.78, P = 0.13), and 1.53 (95% CI, 1.12-2.09, P = 0.007) for all-cause mortality, respectively. A nonlinear relationship between plasma fibrinogen and CV and all-cause mortality was observed.

CONCLUSIONS

An elevated plasma fibrinogen level was significantly associated with an increased risk of CV and all-cause mortality in patients undergoing PD.

Fibrinogen/Albumin ratio: A more powerful prognostic index for patients with end-stage renal disease

BACKGROUND

Microinflammation is linked to an increased risk of death due to cardiovascular disease (CVD) in patients with end-stage renal disease (ESRD). Although the fibrinogen/albumin ratio (FAR), a novel inflammatory marker, has been shown to predict mortality in various diseases, limited evidence is available for its role in ESRD. The purpose of this study is to explore the prognostic value of the FAR in ESRD patients on peritoneal dialysis (PD).

METHODS

In this retrospective observational study, we enrolled patients with ESRD who underwent PD therapy in our hospital between 1 January 2011 and 31 December 2017. The Kaplan-Meier method and Cox proportional hazards models were used to determine the contact between the FAR level and mortality.

RESULTS

A total of 562 patients were enrolled in our research. The median FAR was 0.12, and patients were divided into two groups (low FAR group: FAR < 0.12, n = 250, and high FAR group: FAR ≥ 0.12, n = 312) according to the median FAR. Kaplan-Meier curves showed that the cumulative incidences of both all-cause mortality and CVD mortality were significantly higher in patients with FAR ≥ 0.12 (both P < .001). In multivariable analysis, the high FAR group had an important increased risk of all-cause and CVD mortality (HR: 1.80; 95% CI: 1.03-3.14, P = .038 and HR: 2.31; 95% CI: 1.17-4.59, P = .016, respectively).

CONCLUSIONS

Our results suggest that a high baseline FAR value is an independent prognostic factor in ESRD patients on PD.

Association between Albumin-Globulin Ratio and Mortality in Patients with Chronic Kidney Disease

Background: Malnutrition and inflammation are highly prevalent and tightly regulated with each other in chronic kidney disease (CKD) patients. Inflammation can lead to malnutrition in patients with sufficient nourishment, while malnutrition may also induce an inflammatory response. This study investigated whether the albumin-globulin ratio (AGR) can predict the mortality risk in CKD patients. Methods: We enrolled 956 stage 3–5 CKD patients retrospectively at a medical center. Patients’ baseline characteristics including demographics, laboratory data, pharmacotherapy, and comorbidities were collected for statistical adjustments. The study patients were stratified into three AGR groups according to similar magnitudes of hazards for mortality as follows: low AGR group, AGR ≤ 1.0; moderate AGR group, 1.1 ≤ AGR < 1.3; high AGR group, AGR ≥1.3. Multivariate Cox proportional hazard analysis was performed to evaluate the association of the AGR with the study outcomes, including overall and cardiovascular disease (CVD) mortality. Results: During a median follow-up duration of 2.44 years, 108 (11.3%) deaths were recorded and 50 patients died from CVD. In adjusted model 1, the moderate AGR group was associated with hazard ratios (HR) of 0.57 (95% CI = 0.36–0.90, p = 0.016) and 0.52 (95% CI = 0.28–0.98, p = 0.043) for all-cause and CVD mortality compared with the low AGR group, respectively. The high AGR group was associated with HRs of 0.49 (95% CI = 0.27–0.90, p = 0.021) and 0.27 (95% CI = 0.1–0.74, p = 0.01) for all-cause and CVD mortality compared with the low AGR group, respectively. Similar results were obtained in the adjusted model 2 (inverse probability of the group weighted Cox model). In addition, the association between the AGR and mortality risk remained significant when the AGR was treated as a continuous variable. Conclusion: AGR is a significant biomarker predicting overall and cardiovascular mortality risk independent of various important factors amongst stage 3–5 CKD patients. We suggest that the AGR may be a simple and inexpensive measurement for detecting CKD patients at risk of mortality.

Physical Activity in Patients Treated With Peritoneal Dialysis: A Systematic Review and Meta-analysis

BACKGROUND

Exercise has been shown to be of benefit in the general population and in patients with chronic diseases. Despite a lack of compelling evidence, patients with end-stage kidney disease (ESKD) treated with peritoneal dialysis (PD) are often discouraged from participating in exercise programs that include weight lifting due to concerns about the development of hernias and leaks. The actual effects of physical activity with or without structured exercise programs for patients on PD remain unclear.

OBJECTIVE

To determine the risks and benefits of physical activity in the ESKD population treated with PD.

DESIGN

Systematic review and meta-analysis.

SETTING

Included all studies that met our criteria regardless of country of origin.

PATIENTS

Adult patients with ESKD treated with PD.

MEASUREMENTS

Descriptive and quantitative analysis of our primary and secondary outcome variables.

METHODS

We searched MEDLINE, Embase, CINAHL, and Cochrane Central Register of Controlled Trials for observational and interventional studies examining the effects of physical activity in patients on PD. A systematic review and meta-analysis was conducted of the identified studies. The primary outcomes of interest included patient-centered outcomes of mental health, physical functioning, fatigue, quality of life, and adverse events. Secondary outcomes included nutritional measures, lipid profile, blood pressure changes, maximum heart rate, resting heart rate, maximal oxygen consumption, muscle development, cognitive function, and markers of inflammation.

RESULTS

Of 1828 studies identified by the literature search, 12 met the inclusion criteria including 6 interventional and 6 observational studies. There was limited information on the patient important outcomes. However, there is some evidence for improvements in burden of kidney disease, physical function, and some mental health measures with physical activity.

LIMITATIONS

Lack of well-designed randomized controlled trials impaired our ability to determine the benefits and risks of increasing physical activity.

CONCLUSIONS

There is limited evidence of benefit with increased levels of physical activity in PD patients. Further research is needed to define the exercise program that is likely to be of most benefit to patients treated with PD.

Overhydration Is a Strong Predictor of Mortality in Peritoneal Dialysis Patients - Independently of Cardiac Failure

Background

Overhydration is a common problem in peritoneal dialysis patients and has been shown to be associated with mortality. However, it still remains unclear whether overhydration per se is predictive of mortality or whether it is mainly a reflection of underlying comorbidities. The purpose of our study was to assess overhydration in peritoneal dialysis patients using bioimpedance spectroscopy and to investigate whether overhydration is an independent predictor of mortality.

Methods

We analyzed and followed 54 peritoneal dialysis patients between June 2008 and December 2014. All patients underwent bioimpedance spectroscopy measurement once and were allocated to normohydrated and overhydrated groups. Overhydration was defined as an absolute overhydration/extracellular volume ratio > 15%. Simultaneously, clinical, echocardiographic and laboratory data were assessed. Heart failure was defined either on echocardiography, as a reduced left ventricular ejection fraction, or clinically according to the New York Heart Association functional classification. Patient survival was documented up until December 31^st 2014. Factors associated with mortality were identified and a multivariable Cox regression model was used to identify independent predictors of mortality.

Results

Apart from higher daily peritoneal ultrafiltration rate and cumulative diuretic dose in overhydrated patients, there were no significant differences between the 2 groups, in particular with respect to gender, body mass index, comorbidity and cardiac medication. Mortality was higher in overhydrated than in euvolemic patients. In the univariate analysis, increased age, overhydration, low diastolic blood pressure, raised troponin and NTproBNP, hypoalbuminemia, heart failure but not CRP were predictive of mortality. After adjustment, only overhydration, increased age and low diastolic blood pressure remained statistically significant in the multivariate analysis.

Conclusions

Overhydration remains an independent predictor of mortality even after adjustment for heart failure in peritoneal dialysis patients and should therefore be actively sought and managed in order to improve survival in this population.