Association between the malnutrition-inflammation score and post-transplant anaemia

The Relation of Serum Dehydroepiandrosterone Sulfate Level to Protein Energy Wasting in Hemodialysis Patients

Protein-energy wasting (PEW) is a major risk for morbidity and mortality in hemodialysis (HD) patients. The change in the concentration of dehydroepiandrosterone sulfate (DHEA-S) may play a role in PEW. The aim of this work was to study the possible relationship between serum DHEA-S levels and various nutritional and inflammatory parameters in a cohort of HD patients. In total, 78 HD patients (47 males and 31 females) were included in this crosssectional observational study. In addition to taking their history, clinical examinations, and routine laboratory investigations, the nutritional status was assessed, and their serum DHEA-S was measured. Nutritional status was assessed by anthropometric measures, bioelectrical impedance analysis, malnutrition inflammation scores, and subjective global assessments. A diagnosis of malnutrition was made based on the recommendations of the International Society of Renal Nutrition and Metabolism. The relationship between DHEA-S and various nutritional parameters was analyzed. Eighteen patients (23.1%) suffered from PEW. Those with PEW had a longer duration of HD (P = 0.04), and lower serum levels of creatinine (P = 0.003), hemoglobin (P = 0.01), albumin (P <0.0001), cholesterol (P = 0.02), and DHEA-S (P = 0.01). Among the variables, serum DHEA-S levels were significant predictors of PEW in this cohort (odds ratio: 0.976; 95% confidence interval: 0.954-1.0; P = 0.04). PEW is frequently encountered in HD patients. Decreased serum DHEA-S levels were associated with PEW in male HD patients. Further studies are needed to assess the effect of hormone supplementation on this serious disorder in HD patients.

Female Specific Association of Low Insulin-Like Growth Factor 1 (IGF1) Levels with Increased Risk of Premature Mortality in Renal Transplant Recipients

Associations between insulin-like growth factor 1 (IGF1) and mortality have been reported to be female specific in mice and in human nonagenarians. Intervention in the growth hormone (GH)-IGF1 axis may particularly benefit patients with high risk of losing muscle mass, including renal transplant recipients (RTR). We investigated whether a potential association of circulating IGF1 with all-cause mortality in stable RTR could be female specific and mediated by variation in muscle mass. To this end, plasma IGF1 levels were measured in 277 female and 343 male RTR by mass spectrometry, and their association with mortality was assessed by Cox regression. During a median follow-up time of 5.4 years, 56 female and 77 male RTR died. In females, IGF1 was inversely associated with risk (hazard ratio (HR) per 1-unit increment in log2-transformed (doubling of) IGF1 levels, 95% confidence interval (CI)) of mortality (0.40, 0.24-0.65; p < 0.001), independent of age and the estimated Glomerular filtration rate (eGFR). In equivalent analyses, no significant association was observed for males (0.85, 0.56-1.29; p = 0.44), for which it should be noted that in males, age was negatively and strongly associated with IGF1 levels. The association for females remained materially unchanged upon adjustment for potential confounders and was furthermore found to be mediated for 39% by 24 h urinary creatinine excretion. In conclusion, low IGF1 levels associate with an increased risk of all-cause mortality in female RTR, which may link to conditions of low muscle mass that are known to be associated with poor outcomes in transplantation patients. For males, the strongly negative association of age with IGF1 levels may explain why low IGF1 levels were not found to be associated with an increased risk of all-cause mortality.

Inflammation and Apparent Treatment-Resistant Hypertension in Patients With Chronic Kidney Disease

Apparent treatment-resistant hypertension (ATRH) is highly prevalent and associated with cardiovascular disease risk in patients with chronic kidney disease. We analyzed the association of inflammatory biomarkers with ATRH and its complications in patients with chronic kidney disease. ATRH was defined as blood pressure ≥140/90 mm Hg while taking ≥3 antihypertensive medications or blood pressure <140/90 mm Hg while taking ≥4 medications. Analyses included 1359 CRIC study (Chronic Renal Insufficiency Cohort) participants with ATRH and 2008 hypertensive participants without. Logistic regression was used to examine cross-sectional associations of inflammatory biomarkers and ATRH adjusting for demographic, lifestyle, and clinical risk factors and treatments. Cox proportional hazards models were used to assess the impact of inflammatory biomarkers on associations of ATRH with composite cardiovascular disease and mortality beyond conventional risk factors. Multivariable-adjusted odds ratio (95% CI) of ATRH for the highest tertile versus the lowest tertile of inflammatory biomarker levels was 1.29 (95% CI, 1.05-1.59) for IL (interleukin)-6, 1.49 (95% CI, 1.20-1.85) for TNF-α (tumor necrosis factor-α), and 0.77 (95% CI, 0.63-0.95) for TGF-β (transforming growth factor-β). High-sensitivity CRP (C-reactive protein), fibrinogen, IL-1β, and IL-1 receptor antagonist were not significantly associated with ATRH. Adding inflammatory biomarkers to Cox models did not attenuate the significant association of ATRH with cardiovascular disease and mortality. Our findings show higher levels of IL-6 and TNF-α and lower levels of TGF-β were independently associated with odds of ATRH. Targeting specific inflammatory pathways may improve blood pressure control in patients with chronic kidney disease.

Relationship between protein-energy wasting in adults with chronic hemodialysis and the response to treatment with erythropoietin

BACKGROUND

It is known that one of the leading causes of morbidity in chronic kidney disease (CKD) is the anemic syndrome. Although the pathogenic mechanisms of anemia are multiple, erythropoietin deficiency appears as the dominant factor. Patients in hemodialysis (HD) have a high prevalence of protein energy wasting (PEW) that may explains the poor response to Erythropoietin (EPO).

METHODS

Retrospective cohort study of patients on HD from January to December 2014. The participants were classified according to a diagnostic of PEW using the "Malnutrition Inflammation Score" (MIS) and bioimpedance analysis (BIA) measurement of body composition at the start of erythropoietin therapy and after 3 months of follow up. We performed descriptive statistics and analyzed the differences between groups with and without PEW considering their responsiveness. In addition, we calculated the relative risk of EPO resistance, considering p value < 0.05 as statistically significant.

RESULTS

Sixty-one patients ended the follow up. Both groups were similar in basal hemoglobin, hematocrit and other hematopoiesis markers (p = NS). Patients without PEW have a decrease risk for poor response to treatment with EPO (RR = 0.562 [95% CI, 0.329-0.961-]) than those with PEW. Finally, hemoglobin concentrations were evaluated at baseline and every four weeks until week 12, finding a statistically significant improvement only in patients without PEW according MIS (p < 0.05).

CONCLUSIONS

PEW is an incremental predictor of poor responsiveness to EPO in HD patients, thus, it is important to consider correcting malnutrition or wasting for a favorable response to treatment with EPO.

Association between malnutrition-inflammation score and risk of subsequent self-reported bone fractures in prevalent kidney transplant recipients

Chronic inflammation and protein energy wasting (PEW) syndrome are common in kidney transplant recipients (KTR). The presence of inflammation and PEW syndrome can directly affect bone resorption and bone formation, leading to bone loss and fractures. We showed PEW is independently associated with new clinically detected bone fractures in prevalent KTR.

INTRODUCTION

Kidney transplant recipients (KTR) have a 4-fold higher risk of fracture compared to the general population. Chronic inflammation and PEW syndrome are common in KTR and are associated with poor outcomes. We hypothesized that the Malnutrition-Inflammation Score (MIS), a validated measure of PEW, is associated with higher risk of bone fractures in KTR.

METHODS

This prospective cohort study included 839 prevalent KTR from a Central European academic center. MIS, a semiquantitative instrument of PEW, was calculated at the study entry. Self-reported history of fractures was recorded during the 2-year follow-up period. The association between MIS and bone fractures was examined in logistic regression analyses with adjustment for age, gender, eGFR, smoking habits, history of pre-transplant bone fractures, and acute rejection.

RESULTS

Mean age was 51 ± 13 years, and 56% of patients were males with median (interquartile range) transplant vintage 69 (38-112) months, estimated glomerular filtration rate 55 ± 21 ml/min/1.73 m², and calculated MIS 3 (2-4) at enrollment. Fifty-five (7%) patients experienced self-reported bone fractures during the 2-year follow-up period. Higher MIS score showed linear association with increased risk of fracture. Each one-point higher MIS was associated with 23% higher risk of bone fractures (odds ratio (OR) and 95% CI 1.23, 1.12-1.34), which remained significant after multivariable adjustments (OR 1.17, 95% CI 1.06-1.29).

CONCLUSION

The MIS is independently associated with new clinically detected bone fractures in prevalent KTR.

Association Between Serum Prealbumin Level and Outcomes in Prevalent Kidney Transplant Recipients

OBJECTIVE(S)

Prealbumin, a transport protein mostly synthesized in the liver, is a marker of nutrition. Although decreased prealbumin levels are associated with increased mortality in end-stage kidney disease patients, its association with mortality in kidney transplant recipients remains unknown. We evaluated the association between prealbumin levels and outcomes in kidney transplant recipients.

DESIGN

This was a prospective prevalent cohort study. This study included 991 kidney transplant recipients enrolled from December 31, 2006, to December 31, 2007, and followed over a 6-year period. Sociodemographic, past medical history, clinical, and laboratory data were collected at the study entry. Associations between prealbumin levels and death with functioning graft, all-cause mortality, and graft loss were examined using survival models.

RESULTS

Serum prealbumin levels showed significant negative correlation with estimated glomerular filtration rate (R = -0.28; P < .001) and high-sensitive C-reactive protein (R = -0.24; P < .001). Each 5 mg/dL lower serum prealbumin level was associated with 20% higher risk of death with functioning graft (subdistribution hazard ratio [95% confidence interval]: 1.20 [1.08-1.35]; P = .001), which persisted after multivariable adjustments (subdistribution hazard ratio [95% confidence interval]: 1.13 [1.00-1.28]; P = .039). Qualitatively similar trend was observed in all-cause mortality; however, there was no association between prealbumin levels and graft loss.

CONCLUSION(S)

Lower serum prealbumin level is associated with increased risk of death with functioning graft in prevalent kidney transplant recipients.

Factors associated with anaemia in kidney transplant recipients in the first year after transplantation: a cross-sectional study

Background

Anaemia after kidney transplantation may reduce quality of life, graft or patient survival. We aimed to determine the prevalence and risk factors for anaemia in the initial 12 months after transplantation.

Methods

We conducted a cross-sectional study at 6 and 12 months after transplantation. Anaemia was defined by World Health Organization criteria taking into consideration erythropoietin use. Logistic regression was used to determine the association between demographic, clinical and pharmacological risk factors for the main outcome of moderate-severe anaemia.

Results

A total of 336 transplant recipients were included and the prevalence of moderate-severe anaemia was 27.4% at 6 months and 15.2% at 12 months. Lower kidney function, female gender, transferrin saturation below 10% and proteinuria were associated with moderate-severe anaemia at both time points. Recent intravenous immunoglobulin treatment was associated with anaemia at 6 months. Recent infection and acute rejection were also associated with anaemia 12 months. Around 20% of patients had at least one blood transfusion but they were uncommon beyond 3 months.

Conclusions

Anaemia remains highly prevalent requiring treatment with erythropoietin and transfusions. Most identifiable risk factors relate to clinical problems rather than pharmacological management, while markers of iron-deficiency remain difficult to interpret in this setting.

Electronic supplementary material

The online version of this article (10.1186/s12882-018-1054-7) contains supplementary material, which is available to authorized users.

Pathogenesis and Treatment Options of Cancer Related Anemia: Perspective for a Targeted Mechanism-Based Approach

Cancer-related anemia (CRA) is a common sign occurring in more than 30% of cancer patients at diagnosis before the initiation of antineoplastic therapy. CRA has a relevant influence on survival, disease progression, treatment efficacy, and the patients' quality of life. It is more often detected in patients with advanced stage disease, where it represents a specific symptom of the neoplastic disease, as a consequence of chronic inflammation. In fact, CRA is characterized by biological and hematologic features that resemble those described in anemia associated to chronic inflammatory disease. Proinflammatory cytokine, mainly IL-6, which are released by both tumor and immune cells, play a pivotal action in CRA etiopathogenesis: they promote alterations in erythroid progenitor proliferation, erythropoietin (EPO) production, survival of circulating erythrocytes, iron balance, redox status, and energy metabolism, all of which can lead to anemia. The discovery of hepcidin allowed a greater knowledge of the relationships between immune cells, iron metabolism, and anemia in chronic inflammatory diseases. Additionally, chronic inflammation influences a compromised nutritional status, which in turn might induce or contribute to CRA. In the present review we examine the multifactorial pathogenesis of CRA discussing the main and novel mechanisms by which immune, nutritional, and metabolic components affect its onset and severity. Moreover, we analyze the status of the art and the perspective for the treatment of CRA. Notably, despite the high incidence and clinical relevance of CRA, controlled clinical studies testing the most appropriate treatment for CRA are scarce, and its management in clinical practice remains challenging. The present review may be useful to indicate the development of an effective approach based on a detailed assessment of all factors potentially involved in the pathogenesis of CRA. This mechanism-based approach is essential for clinicians to plan a safe, targeted, and successful therapy, thereby promoting a relevant amelioration of patients' quality of life.

Advanced glycation end products (AGEs) estimated by skin autofluorescence are related with cardiovascular risk in renal transplant

Background

Advanced glycation end products (AGEs) accumulation, a measure of cumulative metabolic stress, constitute a novel pathogenic mechanism involved in aging, diabetes, cardiovascular (CVD) and chronic kidney disease (CKD). Despite removal of uremic toxins and AGEs after a successful renal transplant (RT), CVD remains the leading cause of mortality. We hypothesized that AGEs measurement by Skin Autofluorescence (SAF) might be useful even after a successful RT and thus reflect the high cardiovascular risk burden of these patients.

Methods

189 stable RT (61% men, aged 56±13.0 years), CKD stages 1–4 and >12 months since RT were enrolled. Variables collected comprised comorbid history, medication use, smoking habit, routine biochemistry, subclinical atheromatosis by ankle-brachial-index (ABI) and allograft resistivity index (RI), 24-h ABPM, anthropometry and handgrip strength. AGEs were measured by SAF and expressed in arbitrary units (AU). Vascular age was estimated by Koetsier´s formula (SAF-0.83/0.024) and expected 10-years cardiovascular death risk was calculated with the REGICOR score.

Results

Mean SAF was 3.00±0.83 AU and estimated vascular age 90±34.7 years (30 years above biological age). SAF was higher among men (3.10±0.91 vs 2.81±0.66), diabetic nephropathy (3.49±0.75 vs 2.96±0.83) and steroid users (3.14±0.86 vs 2.71±0.69). We observed a positive correlation of SAF with night-systolic blood pressure (r = 0.25, p = 0.001), parathormone (r = 0.20, p<0.01), phosphate (r = 0.28, p<0.001) and negative with hemoglobin (r = -0.29, p<0.001), CKD-EPI (r = -0.32, p<0.001), albumin (r = -0.17, p<0.05), and dynamometry (r = -0.20, p<0.01). Subclinical vascular atheromatosis (ABI and RI) as well as the REGICOR scale (r = 0.35 p<0.001) were also correlated with SAF. In multivariable analysis age, gender, steroid use, serum phosphate and handgrip strength remained independently associated with SAF.

Conclusions

SAF levels are elevated in RT patients and correlate with CVD risk. Besides age and male sex, our results suggest that phosphate overload, steroid use and nutritional status are important factors linking to AGEs accumulation.

Anemia modifies the prognostic value of glycated hemoglobin in patients with diabetic chronic kidney disease

A common complication of chronic kidney disease (CKD), anemia can influence glycated hemoglobin (HbA1c) levels. In diabetic patients, anemia occurs earlier and with higher severity over the course of CKD stages. To elucidate the effect of hemoglobin (Hb) on the predictive value of HbA1c, we enrolled 1558 diabetic patients with stages 3-4 CKD, categorized according to baseline Hb and HbA1c quartiles. Linear regression revealed that higher HbA1c correlated significantly with higher Hb in the Hb < 10 g/dL group (β = 0.146, P = 0.004). A fully-adjusted Cox regression model revealed worse clinical outcomes in patients with higher HbA1c quartiles in the Hb ≥ 10 g/dL group. Hazard ratios for end-stage renal disease (ESRD), all-cause mortality, and composite endpoint (cardiovascular events and all-cause mortality) in patients with Hb ≥ 10 g/dL and the highest HbA1c quartile were 1.92 (95% confidence interval [CI], 1.17-3.15), 1.76 (95% CI, 1.02-3.03), and 1.54 (95% CI, 1.03-2.31), respectively. By contrast, HbA1c was not associated with clinical outcomes in the Hb < 10 g/dL group. In conclusion, in stages 3-4 diabetic CKD, higher HbA1c is associated with a higher risk of poor clinical outcomes in patients with Hb ≥ 10 g/dL.

Association between anemia at three different time points and new-onset diabetes after kidney transplantation--a retrospective cohort study

PURPOSE

Anemia has been reported to be associated with diabetes, but the association between new-onset diabetes after transplantation (NODAT) and anemia has not been reported.

METHODS

Patients who underwent kidney transplantation and did not have diabetes prior to transplantation were included in this study. Hemoglobin levels and the prevalence of anemia (hemoglobin <12 g/dL in females and <13 g/dL in males) were evaluated at three time points (prior to transplantation, 6 months following transplantation or 1 month before the development of NODAT, 2 years following transplantation, or following the development of NODAT) and were compared between those who developed NODAT and those who did not. Variables associated with the development of anemia were compared between the two groups.

RESULTS

A total of 266 kidney transplant recipients were included, of which 71 (27%) developed NODAT during the time of the follow-up. Hemoglobin and hematocrit levels and the prevalence of anemia were similar in those with and without NODAT at all three time points evaluated. Ferritin levels, prior to transplantation and mean corpuscular volume (MCV) posttransplantation post-NODAT development, were slightly but significantly lower in those with NODAT, although both were within the normal range.

CONCLUSIONS

Pretransplantation ferritin levels and posttransplantation post-NODAT development MCV are inversely associated with the development of NODAT in kidney transplants.

Inflammation and nutritional status assessment by malnutrition inflammation score and its outcome in pre-dialysis chronic kidney disease patients

BACKGROUND

Malnutrition-inflammation complex syndrome (MICS), hyperhomocysteinemia, calcium and phosphate levels derangement have been predicted as important contributing factors for the progression of cardiovascular burden. Among patients with earlier stage of CKD, hypoalbuminaemia and inflammation deliberated as non-traditional cardiovascular risk factors, which add more burden to circulatory disease, mortality and rapid advancement to CKD stage 5.

AIM

The aim of the study is to evaluate inflammation and nutritional status of CKD patients not on dialysis using Malnutrition inflammation score (MIS) and to verify the association with mortality in the follow-up period.

METHODS AND MATERIAL

In this prospective cohort study 129 (66 males, 63 females) pre-dialysis CKD patients enrolled between June 2013 to August 2014 and censored until March 2017. Malnutrition and Inflammation assessed using Malnutrition inflammation score. Blood urea nitrogen, serum creatinine, albumin, Interleukin - 6, highly sensitive C reactive protein (hsCRP), total cholesterol and anthropometric data were analyzed.

RESULTS

The Malnutrition inflammation score in pre-dialysis CKD patients ranged from 0 to 18 with the median score of two. During 36 or more months of follow-up, there were 30 (23.2%) deaths, 35 (27%) patients initiated on hemodialysis, one (0.7%) patient was initiated on peritoneal dialysis, two (1.4%) patients underwent renal transplantation and two (1.4%) patients were lost for follow-up. In this study, 33% had varying degree of malnutrition and inflammation. Patients who had MIS ≥7 had significant increase in IL-6 (p = 0.003) and HsCRP levels (p < 0.001) when compared with other tertiles of MIS. ROC curve analysis of MIS showed 56.5% sensitivity and 81% specificity in predicting death rate (AUC 0.709; 95% CI 0.604-0.815, p < 0.001). Kaplan-Meier survival analysis showed MIS ≥7 had a strong association (log rank test, p < 0.001) with mortality during 36 and more months of follow-up time. In unadjusted analyses, MIS (HR 1.140; 95% CI 1.054-1.233; p < 0.05) and HsCRP (HR 2.369; 95% CI 1.779-3.154; p < 0.001) found to be predictors of mortality. MIS and HsCRP remained predictors of mortality even after adjustments.

CONCLUSIONS

This study shows MIS is an important factor that determines mortality in pre-dialysis CKD patients during 36 and more months of follow-up time. Patients with MIS ≥7 have high risk for mortality and needs close monitoring. In clinical setting application of MIS has a greater utilization in pre-dialysis CKD patients. Further research with longitudinal assessment of MIS and its association with outcomes are warranted. Pre-dialysis CKD patients should be assessed for their nutritional status and inflammation using MIS regularly to prevent malnutrition and its associated complications through appropriate medical and nutritional intervention.

Association of symptoms of insomnia and sleep parameters among kidney transplant recipients

OBJECTIVE

Insomnia complaints are frequent among kidney transplant (kTx) recipients and are associated with fatigue, depression, lower quality of life and increased morbidity. However, it is not known if subjective insomnia symptoms are associated with objective parameters of sleep architecture. Thus, we analyze the association between sleep macrostructure and EEG activity versus insomnia symptoms among kTx recipients.

METHODS

Participants (n₁=100) were selected from prevalent adult transplant recipients (n₀=1214) followed at a single institution. Insomnia symptoms were assessed by the Athens Insomnia Scale (AIS) and standard overnight polysomnography was performed. In a subgroup of patients (n₂=56) sleep microstructure was also analyzed with power spectral analysis.

RESULTS

In univariable analysis AIS score was not associated with sleep macrostructure parameters (sleep latency, total sleep time, slow wave sleep, wake after sleep onset), nor with NREM and REM beta or delta activity in sleep microstructure. In multivariable analysis after controlling for covariables AIS score was independently associated with the proportion of slow wave sleep (β=0.263; CI: 0.026-0.500) and REM beta activity (β=0.323; CI=0.041-0.606) (p<0.05 for both associations).

CONCLUSIONS

Among kTx recipients the severity of insomnia symptoms is independently associated with higher proportion of slow wave sleep and increased beta activity during REM sleep but not with other parameters sleep architecture. The results suggest a potential compensatory sleep protective mechanism and a sign of REM sleep instability associated with insomnia symptoms among this population.

Depressive Symptoms Are Associated With Objectively Measured Sleep Parameters in Kidney Transplant Recipients

STUDY OBJECTIVES

Both depression and sleep complaints are very prevalent among kidney transplant (kTx) recipients. However, details of the complex relationship between sleep and depression in this population are not well documented. Thus, we investigated the association between depressive symptoms and sleep macrostructure parameters among prevalent kTx recipients.

METHODS

Ninety-five kTx recipients participated in the study (54 males, mean ± standard devation age 51 ± 13 years, body mass index 26 ± 4 kg/m2, estimated glomerular filtration rate 53 ± 19 ml/min/1.73 m2). Symptoms of depression were assessed by the Center for Epidemiologic Studies - Depression Scale (CES-D). After 1-night polysomnography each recording was visually scored and sleep macrostructure was analyzed.

RESULTS

The CES-D score was significantly associated with the amount of stage 2 sleep (r = 0.20, P < .05), rapid eye movement (REM) latency (r = 0.21, P < .05) and REM percentage (r = -0.24, P < .05), but not with the amount of slow wave sleep (r = -0.12, P > .05). In multivariable linear regression models the CES-D score was independently associated with the amount of stage 2 sleep (β: 0.205; confidence interval: 0.001-0.409; P = .05) and REM latency (β: 0.234; confidence interval: 0.001-0.468; P = .05) after adjustment for potential confounders.

CONCLUSIONS

Depressive symptoms among kTx recipients are associated with increased amount of stage 2 sleep and prolonged REM latency. Further studies are needed to confirm our findings and understand potential clinical implications.

Inflammation and Arterial Stiffness in Chronic Kidney Disease: Findings From the CRIC Study

BACKGROUND

Chronic kidney disease (CKD) and arterial stiffness are associated with increased cardiovascular morbidity and mortality. Inflammation is proposed to have a role in the development of arterial stiffness, and CKD is recognized as a proinflammatory state. Arterial stiffness is increased in CKD, and cross-sectional data has suggested a link between increased inflammatory markers in CKD and higher measures of arterial stiffness. However, no large scale investigations have examined the impact of inflammation on the progression of arterial stiffness in CKD.

METHODS

We performed baseline assessments of 5 inflammatory markers in 3,939 participants from the chronic renal insufficiency cohort (CRIC), along with serial measurements of arterial stiffness at 0, 2, and 4 years of follow-up.

RESULTS

A total of 2,933 participants completed each of the follow-up stiffness measures. In cross-sectional analysis at enrollment, significant associations with at least 2 measures of stiffness were observed for fibrinogen, interleukin-6, high-sensitivity C-reactive protein, proteinuria, and composite inflammation score after adjustment for confounders. In longitudinal analyses, there were few meaningful correlations between baseline levels of inflammation and changes in metrics of arterial stiffness over time.

CONCLUSION

In a large cohort of CKD participants, we observed multiple significant correlations between initial markers of inflammation and metrics of arterial stiffness, but baseline inflammation did not predict changes in arterial stiffness over time. While well-described biologic mechanisms provide the basis for our understanding of the cross-sectional results, continued efforts to design longitudinal studies are necessary to fully elucidate the relationship between chronic inflammation and arterial stiffening.

Anemia and markers of erythropoiesis in pediatric kidney transplant recipients compared to children with chronic renal failure

PTA and anemia of CKD share a similar pathogenesis. However, PTA may be disproportionate to the reduction in the GFR. Data relating to the mechanism of PTA are scarce. We evaluated the erythropoiesis parameters in pediatric kidney recipients compared to children with CKD. A total of 100 patients (54 post-kidney TX, 46 with CKD) were enrolled in the single-center cohort study. GFR was found to be significantly lower in the CKD group (49.7±22.4 vs 72.9±28.5 mL/min/1.73 m², P<.001); anemia was significantly more common in the TX patients (52% vs 41.3%, P<.001). Iron transferrin saturation and serum ferritin levels were lower in the CKD patients. In both groups, hemoglobin Z scores significantly correlated with GFR (R=.31, P=.07). This correlation was more prominent in the CKD group (R=.43, P=.008) compared to the TX group (R=.31, P=.04). Anemia was significantly more common in the TX patients than in the CKD patients despite a better GFR. The higher prevalence of anemia in the TX group could not be explained by an iron deficiency or reduced EPO production. We speculate that immunosuppressive therapy together with resistance to EPO may play a role in the pathogenesis of post-transplantation anemia.

Association Between Serum Leptin Level and Mortality in Kidney Transplant Recipients

OBJECTIVE

Leptin is a hormone made by adipocytes and associated with hypertension, inflammation, and coronary artery disease. Low serum leptin level was associated with higher risk of death in patients with advanced chronic kidney disease. Little is known about the association of serum leptin with outcomes in kidney transplant recipients.

DESIGN

Prospective prevalent cohort.

SETTING AND SUBJECT

We collected sociodemographic and clinical parameters, medical and transplant history, and laboratory data of 979 prevalent kidney transplant recipients. Associations between serum leptin level and death with a functioning graft, all-cause death, and death-censored graft loss over a 6-year follow-up period were examined in survival models.

RESULTS

Serum leptin levels showed moderate negative correlation with eGFR (R = -0.21, P < .001) and positive correlations with BMI (R = 0.48, P < .001) and C-reactive protein (R = 0.20, P < .001). Each 10 ng/mL higher serum leptin level was associated with 7% lower risk of death with functioning graft (hazard ratio [HR] (95% confidence interval [CI]), 0.93 (0.87-0.99)), and this association persisted after adjustment for confounders: HR (95% CI), 0.90 (0.82-0.99). Similar associations were found with all-cause death as outcome. The association between serum leptin level and risk of graft loss was nonlinear, and only low serum leptin level was associated with higher risk of graft loss.

CONCLUSIONS

In prevalent kidney transplant recipients, lower serum leptin was an independent predictor of death.

Adipocytokines in renal transplant recipients

In the last two decades, perceptions about the role of body fat have changed. Adipocytes modulate endocrine and immune homeostasis by synthesizing hundreds of hormones, known as adipocytokines. Many studies have been investigating the influences and effects of these adipocytokines and suggest that they are modulated by the nutritional and immunologic milieu. Kidney transplant recipients (KTRs) are a unique and relevant population in which the function of adipocytokines can be examined, given their altered nutritional and immune status and subsequent dysregulation of adipocytokine metabolism. In this review, we summarize the recent findings about four specific adipocytokines and their respective roles in KTRs. We decided to evaluate the most widely described adipocytokines, including leptin, adiponectin, visfatin and resistin. Increasing evidence suggests that these adipocytokines may lead to cardiovascular events and metabolic changes in the general population and may also increase mortality and graft loss rate in KTRs. In addition, we present findings on the interrelationship between serum adipocytokine levels and nutritional and immunologic status, and mechanisms by which adipocytokines modulate morbidity and outcomes in KTRs.

Association between serum resistin level and outcomes in kidney transplant recipients

Resistin is an adipocytokine that is associated with inflammation, coronary artery disease, and other types of cardiovascular disease among patients with normal kidney function. However, little is known about the association of resistin with outcomes in kidney transplant recipients. We collected socio-demographic and clinical parameters, medical and transplant history, and laboratory data from 988 prevalent kidney transplant recipients enrolled in the Malnutrition-Inflammation in Transplant-Hungary Study (MINIT-HU study). Serum resistin levels were measured at baseline. Associations between serum resistin level and death with a functioning graft over a 6-year follow-up period were examined in unadjusted and adjusted models. The mean±SD age of the study population was 51 ± 13 years, among whom 57% were men and 21% were diabetics. Median serum resistin concentrations were significantly higher in patients who died with a functioning graft as compared to those who did not die during the follow-up period (median [IQR]: 22[15-26] vs. 19[14-22] ng/ml, respectively; P < 0.001). Higher serum resistin level was associated with higher mortality risk in both unadjusted and fully adjusted models: HRs (95% CI): 1.33(1.16-1.54) and 1.21(1.01-1.46), respectively. In prevalent kidney transplant recipients, serum resistin was an independent predictor of death with a functioning graft.

Anemia control in kidney transplant recipients using once-monthly continuous erythropoietin receptor activator: a prospective, observational study

In a multicenter, prospective, observational study of 279 kidney transplant recipients with anemia, the efficacy and safety of once-monthly continuous erythropoietin receptor activator (C.E.R.A.) were assessed to a maximum of 15 months. The main efficacy variable was the proportion of patients achieving a hemoglobin level of 11-12 g/dL at each of visits between months 7 and 9. At study entry, 224 patients (80.3%) were receiving erythropoiesis stimulating agent (ESA) therapy including darbepoetin alfa (98), epoetin beta (61), and C.E.R.A. (45). The mean (SD) time between C.E.R.A. applications was 34.0 (11.9) days. Among 193 patients for whom efficacy data were available, mean (SD) hemoglobin was 11.1 (0.99) g/dL at study entry, 11.5 (1.1) g/dL at month 7, 11.6 (1.3) g/dL at month 9, and 11.4 (1.1) g/dL at month 15. During months 7–9, 20.7% of patients had all hemoglobin values within the range 11-12 g/dL and 64.8% were within 10–13 g/dL. Seven patients (2.5%) discontinued C.E.R.A. due to adverse events or serious adverse events. In this observational trial under real-life conditions, once-monthly C.E.R.A. therapy achieved stable hemoglobin levels in stable kidney transplant recipients with good tolerability, and with no requirement for any dose change in 43% of patients.

Circulating Angiopoietin-2 levels predict mortality in kidney transplant recipients: a 4-year prospective case-cohort study

Angiopoietin 2 (Angpt2) impairs endothelial function by preventing angiopoietin 1 from binding to their common endothelial-specific receptor Tie2. Here, we examined whether circulating Angpt2 predicts outcome in kidney transplant recipients. For this case-cohort study, we selected 130 kidney transplant recipients who had died or returned to dialysis within the first 2 years of follow-up of our cohort study, as well as 130 age- and gender-matched kidney transplant recipients without an event (controls) from a total of 993 kidney transplant recipients. The total of 260 selected patients were followed in median 4 years. Serum Angpt2 at baseline was measured using an in-house immunoluminometric assay. Median Angpt2 concentrations were significantly higher in patients who died [median (interquartile range--IQR) 3.6 (2.8-5.9) ng/ml] as compared to patients who did not die during the study period [2.8 (2.1-4.1) ng/ml; P < 0.001]. Ln (natural log) Angpt2 levels correlated positively with C-reactive protein levels (r = 0.315, P < 0.001) and the Charlson Comorbidity Index (r = 0.188, P = 0.002) and were inversely associated with eGFR (r = -0.301, P < 0.001) hemoglobin (r = -0.269, P < 0.001), and serum albumin concentrations (r = -0.382, P < 0.001). On multivariate analyses, baseline Angpt2 levels independently predicted all-cause mortality (multivariable-adjusted hazard ratio associated with one natural log unit higher Angpt2 level: 1.70 (95% confidence interval: 1.10-2.61)). In our analysis, circulating Angpt2 was an independent predictor of all-cause mortality in stable, prevalent kidney transplant recipients.

Protein energy wasting and transplantation

In patients with advanced renal failure or those undergoing dialysis, protein energy wasting (PEW) is a frequently occurring complication that is associated with increased cardiovascular morbidity and mortality. Fewer data are available for patients after transplantation. In this article, the available data on nutritional status after kidney transplantation is reviewed. It was also found that signs of PEW and microinflammation in patients undergoing kidney transplantation are associated with both impaired transplantation outcomes and decreased patient survival. Data are lacking on nutritional support and outcomes after transplantation. Only 1 study revealed a possible relationship between healthier eating habits and better outcomes in patients who have undergone transplantation. More data support the notion that sufficient physical exercise improves graft survival and patient outcome after kidney transplantation. Future studies on nutritional support in patients with signs of PEW and microinflammation immediately after transplantation could reveal whether such a strategy improves renal and patient outcomes.

Renal interstitial fibrosis in 0-hour biopsy as a predictor of post-transplant anemia

BACKGROUND/AIMS

Anemia is common in kidney transplant patients and may cause adverse cardiovascular events. Several studies have reported some predictors of post-transplant anemia. However, associations between the pathological findings in the 0-hour biopsy and anemia have not been well described.

METHODS

258 consecutive kidney transplant patients were enrolled in this retrospective study. The patients were divided into two groups, according to the presence or absence of interstitial fibrosis and tubular atrophy (IF/TA) in the 0-hour biopsy: the IF/TA group with fibrotic area ≥5% (n = 131) and the non-IF/TA group with fibrotic area <5% (n = 127). We examined the association between IF/TA and post-transplant anemia.

RESULTS

Serial changes in hemoglobin levels in the IF/TA group were lower than in the non-IF/TA group (p = 0.007). Anemia at 12 months was found in 53% of the IF/TA group, and 35% of the non-IF/TA group (p = 0.004). Even after adjustment for several confounders including graft function, the presence of IF/TA was independently associated with post-transplant anemia at 12 months (odds ratio 1.88, 95% confidence interval 1.06-3.36, p = 0.031). This association was still significant in a subgroup with normal graft function.

CONCLUSIONS

IF/TA in the 0-hour biopsy specimen is one of the predictors for post-transplant anemia and can be used to identify patients who need the treatment with erythropoiesis-stimulating agents.

Renal function is independently associated with red cell distribution width in kidney transplant recipients: a potential new auxiliary parameter for the clinical evaluation of patients with chronic kidney disease

Red cell distribution width (RDW), a measure of heterogeneity in the size of circulating erythrocytes, reportedly predicts mortality. Similarly to RDW, impaired renal function is also associated with inflammation and protein-energy wasting. This study assessed if renal function is associated with RDW independent of relevant confounders in stable kidney transplant recipients. We examined the association between RDW and estimated glomerular filtration rate (eGFR) in a cohort of 723 prevalent kidney transplanted recipients who were not receiving erythropoietin-stimulating agents. Associations were examined in regression models adjusted for age, sex, comorbidity, blood haemoglobin, iron indices, markers of nutritional status and inflammation, markers of bone and mineral metabolism and the use of immune suppressants. Lower eGFR was significantly associated with higher RDW (r = -0·382, P < 0·001). This association remained highly significant even after multivariate adjustments where 10 ml/min decrease in the eGFR was significantly associated with an increase of the RDW values (B10 ml/min decrease  =  0·078; 95% confidence interval: 0·044-0·111). The results were consistent in subgroups of patients with different levels of haemoglobin, chronic kidney disease status and various markers of inflammation and iron status. Lower eGFR is associated with higher RDW, independent of comorbidity, iron deficiency, inflammation and nutritional status in kidney transplant recipients.

Association between albuminuria, kidney function, and inflammatory biomarker profile in CKD in CRIC

BACKGROUND AND OBJECTIVES

Increased risk of mortality in patients with CKD has been attributed to inflammation. However, the association between kidney function, albuminuria, and biomarkers of inflammation has not been examined in a large cohort of CKD patients.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

This study measured the plasma levels of IL-1β, IL-1 receptor antagonist (IL-1RA), IL-6, TNF-α, TGF-β, high-sensitivity C-reactive protein (hs-CRP), fibrinogen, and serum albumin in 3939 participants enrolled in the Chronic Renal Insufficiency Cohort study between June 2003 and September 2008. An inflammation score was established based on plasma levels of IL-1β, IL-6, TNF-α, hs-CRP, and fibrinogen. Estimated GFR (eGFR) and serum cystatin C were used as measures of kidney function. Albuminuria was quantitated by urine albumin to creatinine ratio (UACR).

RESULTS

Plasma levels of IL-1β, IL-1RA, IL-6, TNF-α, hs-CRP, and fibrinogen were higher among participants with lower levels of eGFR. Inflammation score was higher among those with lower eGFR and higher UACR. In regression analysis adjusted for multiple covariates, eGFR, cystatin C, and UACR were strongly associated with fibrinogen, serum albumin, IL-6, and TNF-α. Each unit increase in eGFR, cystatin C, and UACR was associated with a -1.2% (95% confidence interval, -1.4, -1), 64.9% (56.8, 73.3) and 0.6% (0.4, 0.8) change in IL-6, respectively (P<0.001).

CONCLUSIONS

Biomarkers of inflammation were inversely associated with measures of kidney function and positively with albuminuria.

Clinical outcomes in kidney transplant recipients receiving long-term therapy with inhibitors of the mammalian target of rapamycin

Inhibitors of the mammalian target of rapamycin (mTOR), sirolimus and everolimus, reduce the incidence of acute rejection following kidney transplantation, but their impact on clinical outcomes beyond 2 years after transplantation is unknown. We examined risks of mortality and allograft loss in a prospective observational study of 993 prevalent kidney transplant recipients who enrolled a median of 72 months after transplantation. During a median follow-up of 37 months, 87 patients died and 102 suffered allograft loss. In the overall population, use of mTOR inhibitors at enrollment was not associated with altered risk of allograft loss, and their association with increased mortality was of borderline significance. However, history of malignancy was the strongest predictor of both mortality and therapy with an mTOR inhibitor. Among patients without a history of malignancy, use of mTOR inhibitors was associated with significantly increased risk of mortality in propensity score-adjusted (hazard ratio [HR] 2.6; 95% CI, 1.2, 5.5; p = 0.01), multivariable-adjusted (HR 3.2; 95% CI, 1.5, 6.5; p = 0.002) and one-to-one propensity score-matched analyses (HR 5.6; 95% CI 1.2, 25.7; p = 0.03). Additional studies are needed to examine the long-term safety of mTOR inhibitors in kidney transplantation, especially among recipients without a history of malignancy.

Quality of life and protein-energy wasting in kidney transplant recipients

PURPOSE

Chronic kidney disease has profound effects on the health-related quality of life (HRQoL) of patients, with serious physiological, psychological and socio-economic implications. The co-occurrence of protein-energy wasting and inflammation in end-stage renal disease patients is associated with worse HRQoL and increased mortality. We designed this study to examine the relationship between nutritional and inflammatory status and HRQoL in kidney transplant recipients.

METHODS

Data from 100 randomly selected kidney transplant patients were analyzed in a cross-sectional survey. Socio-demographic parameters, laboratory results, transplantation-related data, comorbidities, medication and malnutrition-inflammation score (MIS) (Kalantar Score) were tabulated at baseline. Patients completed the Kidney Disease Quality of Life-SF (KDQoL-SF™) self-administered questionnaire.

RESULTS

Mean age was 51 ± 13 years, median (interquartile range, IQR) time since transplantation 66 (83) months, 57% were men, and 19% had diabetes. The median (IQR) MIS was 3 (3). The MIS significantly and negatively correlated with almost all HRQoL domains analyzed, and this association remained significant in multivariate linear regression analysis for the log-transformed scores on energy/fatigue (β = -0.059 P < 0.001), bodily pain (β = -0.056 P = 0.004), physical functioning (β = -0.029, P = 0.022) and symptoms/problems (β = -0.023 P = 0.005) domains after statistical correction for age, gender, eGFR, dialysis vintage, Charlson Comorbidity Index and occupational status. Additionally, cubic spline analyses revealed linearly increasing, "dose-response" relationship between almost all domains of KDQoL-SF™ and the MIS.

CONCLUSIONS

Malnutrition-inflammation score is independently associated with different dimensions of HRQoL in kidney transplant recipients.

Lack of association between objectively assessed sleep disorders and inflammatory markers among kidney transplant recipients

PURPOSE

In patients on dialysis, the results of studies examining the association between sleep disorders and inflammation are controversial. We assessed the association between inflammatory markers and different sleep disorders in a large sample of kidney transplant recipients.

METHODS

Cross-sectional study of 100 randomly selected kidney transplant patients who underwent one-night polysomnography ("sleep disorders evaluation in patients after kidney transplantation study") to diagnose obstructive sleep apnea (OSA) and periodic limb movements in sleep (PLMS). Athens Insomnia Scale (AIS) was utilized to assess the prevalence of insomnia. Sociodemographic information and data about medication, comorbidity and laboratory parameters were collected. Levels of inflammatory markers, such as C-reactive protein, serum albumin, white blood cell count, interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α), were measured.

RESULTS

The mean age was 51 ± 13 years, 43% were women, and the prevalence of diabetes was 19%. We found no significant difference in the levels of inflammatory markers between patients with versus without OSA and PLMS. Apnea-hypopnea index showed a significant association with white blood cell count (ρ = 0.23), and weak (ρ < |0.15|), non-significant correlation with the other inflammatory markers. PLM index showed weak (ρ < |0.15|), non-significant correlation with all markers of inflammation. The serum IL-6 level was significantly higher in patients with insomnia (AIS ≥ 10) than in non-insomniacs [median (IQR): 3.2(2.6-5.1) vs. 1.7(1.2-2.9) ng/l; P = 0.009]. The levels of other inflammatory markers were similar between insomniacs and non-insomniacs.

CONCLUSIONS

We did not find any association between the presence of objectively assessed sleep disorders and inflammatory markers in kidney transplant patients.

Serum erythropoietin level and mortality in kidney transplant recipients

BACKGROUND AND OBJECTIVES

Posttransplant anemia is frequently reported in kidney transplant recipients and is associated with worsened patient survival. Similar to high erythropoiesis-stimulating agent requirements, resistance to endogenous erythropoietin may be associated with worse clinical outcomes in patients with ESRD. We examined the association between serum erythropoietin levels and mortality among kidney transplant recipients.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We collected sociodemographic, clinical, medical, and transplant history and laboratory data at baseline in 886 prevalent kidney transplant recipients (mean age 51 ± 13 [SD] years, 60% men, 21% diabetics). A solid-phase chemiluminescent immunometric assay was used to measure serum erythropoietin. Cox proportional hazards regression was used to model the association between baseline serum erythropoietin levels and all-cause mortality risk.

RESULTS

During the median 39-month follow-up, 99 subjects died. The median serum erythropoietin level was 10.85 U/L and hemoglobin was 137 ± 16 g/L. Mortality rates were significantly higher in patients with higher erythropoietin levels (crude mortality rates in the highest to lowest erythropoietin tertiles were 51.7, 35.5, and 24.0 per 1000 patient-years, respectively [P = 0.008]). In unadjusted and also in adjusted Cox models each SD higher serum erythropoietin level significantly predicted all-cause mortality: HR(1SD increase) 1.22 and 1.28, respectively. In adjusted Cox models each SD higher serum erythropoietin/blood hemoglobin ratio also significantly predicted all-cause mortality: HR(1SD increase) 1.32. Serum erythropoietin predicted mortality in all analyzed subgroups.

CONCLUSIONS

In this sample of prevalent kidney transplant recipients, higher serum erythropoietin levels were associated with increased mortality.

Risk factors of post renal transplant anaemia among Sudanese patients, a study in three renal transplant centres

Background

There is a relative lack of recent information about late post kidney transplantation anaemia (PTA), especially in the developing countries; data are scarce about the prevalence and risk factors of PTA. Sudan was a leading country in Africa and Arab world in kidney transplantation. The first kidney transplantation in Sudan was in 1973.

Methods

This is a cross-sectional hospital analytic study enrolling all kidney transplanted recipients following in the transplant referral clinics at Ahmed Gassim, Selma and Ibn Sina Hospitals, Khartoum/Sudan, in the period from 1/8/2010 to 1/9/2010, clinical and laboratory data were obtained from 114 patients, anaemia was defined as Hb levels of < 13 g/dl for male patients and < 12 g/dl for female patients, exclusion criteria were pregnancy, below 18 years old patients, multiple organ transplantation, and patients with less than one year from the transplantation.

Results

The study showed that 39.5% of the patients were anaemic. Univariate analysis showed that late PTA is significantly associated with not using Erythropoietin (EPO) in the pre-transplant period (p = < 0.001), history of rejection (p = 0.003), longer time from transplantation (p = 0.015), and eGFR (p < 0.0001). Multivariate analysis showed that eGFR (p = < 0.001) and not use of EPO in the pre transplant period (p < 0.001) are strong predictors of PTA. The use of Angiotensin converting enzyme inhibitors/Angiotensin receptors blockers (ACEI/ARB), immunosuppressive treatments, presence or absence of co-morbidities, donor type and donor age are not significantly associated with late PTA.

Conclusion

The study concluded that late PTA is common and under recognized. Risk factors for late PTA include renal dysfunction, history of rejection, longer duration of transplantation and not using EPO in the pre-transplant period. Renal dysfunction and not using EPO in the pre-transplant period are major predictors of late PTA.

Associations of pretransplant weight and muscle mass with mortality in renal transplant recipients

BACKGROUND AND OBJECTIVES

The association between pretransplant body composition and posttransplant outcomes in renal transplant recipients is unclear. It was hypothesized that in hemodialysis patients higher muscle mass (represented by higher pretransplant serum creatinine level) and larger body size (represented by higher pretransplant body mass index [BMI]) are associated with better posttransplant outcomes.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Linking 5-year patient data of a large dialysis organization (DaVita) to the Scientific Registry of Transplant Recipients, 10,090 hemodialysis patients were identified who underwent kidney transplantation from July 2001 to June 2007. Cox regression hazard ratios and 95% confidence intervals of death and/or graft failure were estimated.

RESULTS

Patients were 49 ± 13 years old and included 49% women, 45% diabetics, and 27% African Americans. In Cox models adjusted for case-mix, nutrition-inflammation complex, and transplant-related covariates, the 3-month-averaged postdialysis weight-based pretransplant BMI of 20 to <22 and < 20 kg/m(2), compared with 22 to <25 kg/m(2), showed a nonsignificant trend toward higher combined posttransplant mortality or graft failure, and even weaker associations existed for BMI ≥ 25 kg/m(2). Compared with pretransplant 3-month- averaged serum creatinine of 8 to <10 mg/dl, there was 2.2-fold higher risk of combined death or graft failure with serum creatinine <4 mg/dl, whereas creatinine ≥14 mg/dl exhibited 22% better graft and patient survival.

CONCLUSIONS

Pretransplant obesity does not appear to be associated with poor posttransplant outcomes. Larger pretransplant muscle mass, reflected by higher pretransplant serum creatinine level, is associated with greater posttransplant graft and patient survival.