In hemodialysis, adiponectin, and pro-brain natriuretic peptide levels may be subjected to variations in body mass index

Resistance physical exercise modulates metabolic adipokines, decreases body weight, and improves glomerular filtration in patients with chronic kidney disease in hemodialysis

Chronic kidney disease (CKD) is a condition characterized by abnormalities in kidney structure and function that persist for more than 3 months. It is estimated that more than 800 million people in the world have a diagnosis of CKD. To remove the harmful metabolic substances from the body, people with CKD need to perform hemodialysis. Due to their beneficial effects against a wide range of clinical conditions, physical exercise is considered a non-pharmacological therapy. This study aimed to evaluate the beneficial effects of resistance exercise during hemodialysis on metabolic adipokines, myokines, body weight, and glomerular filtration rate in patients living with CKD. Briefly, the blood samples were collected in two moments: immediately before the start of the resistance exercise protocol and 1 week after the end of the protocol. Resistance exercise protocol was performed thrice a week for 12 weeks and applied during hemodialysis sessions. Here, resistance exercise increases the circulating irisin (14.56%; p = 0.0112), handgrip strength (5.70%; p = 0.0036), glomerular filtration rate (25.9%; p = 0.022) and significantly decreases adiponectin (- 55.7%; p = 0.0044), body weight (- 3.7%; p = 0.0001), glucose (- 22%; p = 0.009), and albumin levels (- 9.55%; p = 0.0001). Conversely, leptin levels (- 10.9%; p = 0.38), iron (3.05%; p = 0.705), ferritin (3.24%; p = 0.880), hemoglobin (- 0.52%; p = 0.75), total cholesterol (7.9%; p = 0.19), LDL (- 9.99%; p = 0.15) and HDL (- 4.8%; p = 0.45), did not change after resistance exercise. Interestingly, 1,25 hydroxyvitamin D levels were significantly increased (14.5%; p = 0.01) following resistance exercise. Considering the effect of sex (males vs. females), we found that irisin levels increased in females but not in males after the resistance exercise protocol. Furthermore, handgrip strength and body weight were different, indicating that males had the highest strength and weight. We demonstrated that both males and females had lower albumin levels after the resistance exercise protocol. In conclusion, we suggest that resistance exercise has beneficial effects in the CKD population by modulating adipokines and metabolic myokines and therefore can be used as a non-pharmacological adjunctive therapy in CKD patients undergoing HD.

Superiority of high sensitivity cardiac troponin I over NT-proBNP and adiponectin for 7-year mortality in stable patients receiving haemodialysis

Patients on haemodialysis (HD) have high mortality risk, and prognostic values of the major cardiovascular biomarkers cardiac troponin I (cTnI), N-terminal pro-brain natriuretic peptide (NT-proBNP), and adiponectin should be ascertained over longer follow-up periods using higher-sensitivity assays, which we undertook. In 221 HD patients, levels of high-sensitivity (hs)-cTnI, NT-proBNP, and adiponectin, were measured using high-sensitivity assays, and their associations with all-cause mortality (ACM) and cardiovascular mortality (CVM) were prospectively investigated for 7 years. Higher hs-cTnI and NT-proBNP levels were significant risk factors for ACM and CVM in the Kaplan-Meier analysis. Multivariate Cox proportional hazards analyses in a model including hs-cTnI and NT-proBNP identified log hs-cTnI, but not log NT-proBNP, as an independent risk factor for ACM (HR 2.12, P < 0.02) and CVM (HR 4.48, P < 0.0005). Stepwise analyses identified a high hs-cTnI tertile as a risk factor for ACM (HR 2.31, P < 0.01) and CVM (HR 6.70, P < 0.001). The addition of hs-cTnI to a model including age, CRP, DM, and NT-proBNP significantly improved the discrimination of ACM and CVM each over 7 years. Conclusively, hs-cTnI was superior to NT-proBNP and adiponectin in predicting ACM and CVM over 7 years in HD patients, suggesting the significance of baseline hs-cTnI measurements in long-term management.

Negative correlation of serum adiponectin level with peripheral artery occlusive disease in hemodialysis patients

OBJECTIVE

Adiponectin is a fat-derived hormone that secretes exclusively by adipocytes and has antiatherosclerotic effects. Peripheral arterial occlusive disease (PAOD) is associated with an increased risk of death in hemodialysis (HD) patients. The aim of this study was to evaluate the relationship between serum adiponectin levels and PAOD by ankle-brachial index (ABI) in HD patients.

MATERIALS AND METHODS

Blood samples were obtained from 100 HD patients. Serum adiponectin levels were measured using a commercial enzyme-linked immunosorbent assay kit. ABI values were measured using the automated oscillometric method (VaSera VS-1000). ABI values that <0.9 were included in the low ABI group.

RESULTS

Among the 100 HD patients, 18 of them (18.0%) were in the low ABI group. Compared with patients in the normal ABI group, the patients in the low ABI group had a higher prevalence of diabetes (P = 0.043), older age (P = 0.027), and lower serum adiponectin level (P = 0.003). In addition, the multivariable logistic regression analysis showed that adiponectin (Odds ratio [OR]: 0.927, 95% confidence interval [CI]: 0.867-0.990, P = 0.025) and age (OR: 1.054, 95% CI: 1.002-1.109, P = 0.043) were the independently associated with PAOD in HD patients.

CONCLUSION

In this study, serum adiponectin level was found to be associated with PAOD in HD patients.

N-terminal-pro-B-type-natriuretic peptide associated with 2-year mortality from both cardiovascular and non-cardiovascular origins in prevalent chronic hemodialysis patients

N-terminal-pro-B-type-natriuretic peptide (NT-proBNP) was a predictive marker of cardiovascular disease (CVD)-related death in chronic dialysis patients. NT-proBNP was also correlated with markers of inflammation, malnutrition and protein-energy wasting. We hypothesized whether NT-proBNP was also associated with non-CVD death in chronic dialysis patients. A prospective observational study for incidence of death in chronic dialysis patients was conducted. Prevalent chronic dialysis patients (n = 1310) were enrolled and followed for 24 months. One hundred forty-four deaths were recorded. Area under the curve using ROC analysis for NT-proBNP showed: all causes of death (0.761), CVD-related (0.750), infection and malignancy-related (0.702) and others and unknown (0.745). After adjusting for age, sex, hemodialysis vintage, cardiothoracic ratio, mean pre-dialysis systolic blood pressure, dry weight and basal kidney disease, the hazard ratios (95% confidence intervals) per 1-log NT-proBNP calculated using multivariate Cox analysis were: all causes of death, 3.83 (2.51–5.85); CVD-related, 4.30 (2.12–8.75); infection and malignancy-related, 2.41 (1.17-4.93); and others and unknown origin, 5.63 (2.57–12.37). NT-proBNP was significantly associated not only with CVD-relate but also with non-CVD-related deaths in this population of prevalent chronic dialysis patients.

Body Composition and Mortality Predictors in Hemodialysis Patients

OBJECTIVE

To evaluate how different compartments of body composition can affect survival in hemodialysis (HD) patients.

DESIGN

Multicenter longitudinal observational study of a cohort of patients in HD with 12 months of follow-up.

SETTING

Patients from 34 Nephrocare dialysis units in Portugal were included.

SUBJECTS

A total of 697 patients on maintenance HD during 4 hours 3 days per week were enrolled.

INTERVENTION

Dry weight, presence of diabetes, body mass index (BMI), lean tissue index (LTI), fat tissue index (FTI), body cell mass index (BCMI), albumin and hydration status were recorded at baseline. In all patients, the assessment of body composition was carried out using the Body Composition Monitor (BCM; Fresenius Medical Care a Deutschland GmbH, Germany).

MAIN OUTCOME MEASURE

Survival during a 12-month period of follow-up.

RESULTS

Patient's mean (±standard deviation) age was 65.4 ± 14.3 years, and median (interquartile range) HD vintage was 41 (19-81) months. Patients who died during the study period, had higher age (P < .001), lower dry weight (P = .001), BMI (P < .001), albumin (P < .001), LTI (P = .015), and also lower BCMI (P = .046). Patients with diabetes (P = .045), BMI < 18.5 kg/m(2) (P < .001), albumin < 4.0 g/dL (P < .001), relative overhydration ≥ 15% (P = .001), low FTI (P = .019), and also those in the lowest tertile of BCMI (P = .022) displayed a significantly worse survival. In the Cox regression analysis, the overall mortality of patient was related to low FTI, relative overhydration, BMI < 18.5 kg/m(2), BCMI ≤ 5.2 kg/m(2), and albumin < 4.0 g/dL.

CONCLUSIONS

Several body composition parameters demonstrated to have an important role in predicting 1-year mortality in HD patients. Albumin, FTI, and BMI were useful predictors of mortality in these patients.

Residual urinary output in high body mass index individuals on chronic hemodialysis: A disregarded life vest?

AIM: To assess residual diuresis and diverse variables according to body mass index (BMI).

METHODS: Cross-sectional study (n = 57), with 3 groups. Group A: BMI < 25, n = 22; Group B: BMI 25-30, n = 15; Group C: BMI > 30, n = 20. Diuresis, hematocrit, albumin, C-reactive protein, Malnutrition inflammatory score, Pro-BNP, Troponin T, leptin and insulin levels are expressed as median and ranges (r).

RESULTS: Albumin (g/dL): GA vs GC, 3.70 (r2.20-4.90) vs 3.85 (r3.40-4.90), P = 0.02. Diuresis (mL/d): GA 690 (r0-1780); GB 660 (r60-1800); GC 840 (r40-2840). Diuresis GA vs GC, P = 0.01. Leptin (ng/mL): GA vs GC, 3.81 (r0.78-69.60) vs GC, 32.80 (r0.78-124.50), P < 0.001. Insulin (µU/mL): GA vs GB, 7 (r2-44) vs 11.50 (r4-38), P = 0.02; GA vs GC, 7 (r2-44) vs 19.5 (r5-155), P = 0.0001. Troponin T and Pro-BNP levels were not different. Significant correlations: GC, Insulin-UF: ρ = 0.53; P = 0.03; TroponinT-diuresis: ρ = -0.48, P < 0.05; Pro-BNP-diuresis: ρ = -0.39, P < 0.01; Troponin T-ProBNP: ρ = 0.77, P < 0.0001; albumin-Troponin T: ρ = -0.66, P < 0.0001; albumin-ProBNP: ρ = -0.44, P < 0.05.

CONCLUSION: High BMI associated positively with higher diuresis and albuminemia, and negatively with TropT and Pro-BNP. High BMI-associated better survival may be explained by better urinary output, lowering cardiovascular stress.

A comparison of markers of myocardial injury and their relation to nutritional parameters in hemodialysis patients

BACKGROUND

Serum cardiac troponin T (cTnT) is a valuable marker of ischemic heart disease (IHD) and left ventricular hypertrophy, as well as a mortality predictor in hemodialysis populations. We compared the value of cTnT, creatinine kinase (CK)-MB mass and myoglobin as mortality predictors in our hemodialysis patients and evaluated their relation to nutritional status.

METHODS

A total of 118 hemodialysis patients were prospectively studied from January 2004 to April 2013. Clinical and laboratory evaluations during the 12-month baseline period included the history of IHD, signs of left ventricular hypertrophy (LVH), Kt/V and serum cardiac markers together with the percentage of body fat (%fat), mid-arm circumference (MAC), mid-arm muscle circumference (MAMC), triceps skinfold (TSF) and BMI.

RESULTS

Underweight patients had significantly higher cTnT values (Mann-Whitney, p<0.05). Correlation analysis (Spearman) showed an inverse association between cTnT and TSF (ρ=-0.22, p<0.05), as well as between CK-MB mass and TSF (ρ=-0.26, p<0.01). In men cTnT also correlated inversely with %fat (ρ=-0.27, p<0.05) and BMI (ρ=-0.33, p<0.05). In addition, myoglobin was correlated significantly with MAC, MAMC and albumin. Among cardiac markers cTnT was the only independent variable predicting mortality (Multivariate Cox regression, HR=1.04 CI (1.01-1.07); p<0.01; measurement units 0.01 μg/L).

CONCLUSION

Troponin T and CK-MB mass were significantly elevated in the underweight patient group. Troponin T was the only independent cardiac marker predictor of all cause mortality in our hemodialysis patients.

Body mass index and mortality in patients on maintenance hemodialysis: a meta-analysis

PURPOSE

In patients undergoing maintenance hemodialysis (MHD), increasing numbers of studies have reported a reduced mortality in patients with an increased body mass index (BMI). This article provides a meta-analysis on the assessment of the relationship between BMI and mortality in MHD patients.

METHODS

A systemic literature review was conducted to identify studies that examined all-cause mortality, with or without cardiovascular events, on the basis of bodyweight or obesity measures in MHD population published before October 2012.

RESULTS

Eight observational studies with a total of 190,163 patients were included. Compared to the individuals with a normal BMI, overweight patients and obese patients were associated with lower all-cause mortality [relative risk (RR) 0.86, 95% confidence interval (CI) 0.84-0.88; RR 0.77, 95% CI 0.75-0.78, respectively] and cardiovascular mortality (RR 0.86; 95% CI 0.81-0.91; RR 0.78, 95% CI 0.73-0.83, respectively). Underweight patients had relatively higher all-cause and cardiovascular mortality (RR 1.22, 95% CI 1.20-1.25; RR 1.19, 95% CI 1.11-1.28, respectively). In an obesity-stratified analysis, the patients with moderate or severe obesity presented a strongly decreased all-cause mortality risk (RR 0.64, 95% CI 0.61-0.68) and cardiovascular mortality risk (RR 0.63, 95% CI 0.53-0.75) compared to patients with mild obesity (RR 0.74, 95% CI 0.71-0.77; RR 0.81, 95% CI 0.75-0.87, respectively).

CONCLUSIONS

These findings show that overweight and obese patients have lower all-cause and cardiovascular mortality rates in patients undergoing MHD. Body weight management and optimized nutritional and metabolic support should help to reduce the high mortality rates that are prevalent in the hemodialysis population.

Proteinuria and its relation to diverse biomarkers and body mass index in chronic hemodialysis

Background

Certain adipokines exert direct effects on proteinuria, a cardiovascular risk factor ignored in hemodialysis. We measured different adipokines according to body mass index (BMI) in relation to proteinuria.

Methods

Patients numbered 57: group A (GA), BMI<25, n = 22; GB, BMI 25–30, n = 15; and GC, BMI > 30, n = 20. There were no statistical differences in age, sex, time on dialysis, cause of renal failure, diabetes, hypertension, C-reactive protein, or nutritional status. Measures were taken of 24-hour diuresis and proteinuria, ultrafltration, albumin, pro-brain natriuretic peptide (Pro-BNP), insulin, adiponectin, leptin, and ghrelin.

Results

Proteinuria was signifcantly higher in GC versus (vs) GA (1.5 g/day, range 0.30–14 vs 0.72 g/day, range 0.1–2.7; P < 0.01) and correlated signifcantly with leptin levels (ρ = 0.47, P < 0.05). In GA, elevated levels of Pro-BNP, adiponectin, and ghrelin were associated with lower degrees of proteinuria. Signifcant correlations were found between adiponectin and leptin (ρ = −0.54, P = 0.03), and adiponectin and Pro-BNP (ρ = 0.59, P = 0.02). Though not signifcant, there were more diabetics in GC (GA four, GB three, GC ten). As BMI increased in GB and GC, Pro-BNP, adiponectin, and ghrelin levels decreased signifcantly, while proteinuria, insulin, and homeostasis model assessment of insulin resistance increased. Leptin levels were signifcantly elevated in GC vs GA and GB. In GC, ghrelin correlated signifcantly with Pro-BNP (ρ = 0.51, P = 0.03), while leptin correlation with Pro-BNP was inverse and signifcant in GA (ρ = −0.74, P < 0.001) and inverse and nonsignifcant in GB and GC.

Conclusion

In patients with BMI < 25, higher adiponectin, ghrelin, and Pro-BNP levels were associated with lower proteinuria and leptinemia. In obesity, hyperleptinemia and hyperinsulinemia associated with higher proteinuria; whether decreased adiponectin–ghrelin–ProBNP and/or elevated leptin–insulin levels aggravate proteinuria remains to be determined.

Differential effect of baseline adiponectin on all-cause mortality in hemodialysis patients depending on initial body mass index. Long-term follow-up data of 4.5 years

OBJECTIVES

We sought to investigate the interaction of adiponectin levels and body mass index (BMI) for predicting all-cause mortality in a cohort of hemodialysis (HD) patients.

DESIGN

Longitudinal, observational cohort study.

SETTING

HD unit.

SUBJECTS

Sixty patients (mean age: 64 ± 13 years, 39 men) with end-stage renal disease on maintenance HD followed up for 4.5 years represented the prospective study cohort.

INTERVENTION

Associations between baseline plasma adiponectin levels and initial BMI with all-cause mortality were assessed taking into account the assumption of nonlinear correlations. The association between adiponectin, BMI, and serum levels of interleukin-10 (IL-10) and interleukin-6 (IL-6) with survival was determined cross-sectionally.

MAIN OUTCOME MEASURE

All-cause mortality.

RESULTS

Nonlinear survival modeling showed that there was a U-shaped association of BMI with all-cause mortality, whereas there was an inverse U-shaped association for plasma adiponectin levels. Using a BMI of 24 kg/m(2) as a cutoff, an interaction effect of BMI on the association between adiponectin and mortality was observed (P = .045). In participants with BMI ≥ 24 kg/m(2), each 15 μg/mL increase in plasma adiponectin levels was associated with a decreased hazard of death (hazard ratio: 0.57, 95% CI: 0.32 to 0.99) in unadjusted analysis. In HD patients with BMI < 24 kg/m(2), no significant association was observed between adiponectin and mortality (P = .989). Cross-sectional analysis showed that in the subgroup of patients in whom the protective effect of adiponectin was observed (BMI ≥ 24 kg/m(2)), a positive linear association existed between adiponectin and IL-10 levels (r = 0.345, P = .027) as well as a negative association with IL-6 levels (r = -0.322, P = .040). No association was observed in patients with BMI < 24 kg/m(2), neither with IL-10 nor with IL-6.

CONCLUSIONS

Obesity possibly modifies the effect of adiponectin on all-cause mortality in HD patients, thus explaining the published conflicting results in recent literature regarding the association of plasma adiponectin levels and mortality in chronic kidney disease patients.