Malnutrition, chronic inflammation and atherosclerosis in dialysis patients

Dietary intake and cardiometabolic biomarkers in relation to insulin resistance and hypertension in a middle-aged and elderly population in Beijing, China

This study investigated the relationships of dietary intake and cardiometabolic biomarkers with insulin resistance and hypertension in rural middle-aged and elderly people in China. One hundred and eight middle-aged and elderly adults were recruited in Zhangfang village in May 2014. We measured blood pressure, anthropometric parameters, and biochemical indexes, including high-sensitivity C-reactive protein (hsCRP), soluble intercellular adhesion molecule-1 (sICAM-1), glucose, insulin, and blood lipids. Homeostasis model assessment of insulin resistance index (HOMA-IR) was assessed on the basis of fasting glucose and insulin. We recorded participant demographic characteristics, dietary intake, and lifestyle using questionnaires. Hypertensive participants had higher levels of triglycerides (TG), hsCRP, sICAM-1, body fat percentage (BF%), arm muscle circumference (AMC) and HOMA-IR than nonhypertensive individuals. Hypertensive participants had higher carbohydrate intake but lower intakes of protein and fat. Carbohydrate intake was positively correlated with hsCRP, sICAM-1, TG, BF%, and HOMA-IR, and was negatively correlated with AMC. Protein and fat intakes were negatively correlated with hsCRP and sICAM-1. Protein intake was also significantly negatively correlated with TG and HOMA-IR, and positively correlated with AMC. HOMA-IR was positively correlated with hsCRP, sICAM-1, TG and BF%, and negatively correlated with AMC. Multivariable linear regression indicated that TG, sICAM-1, and hsCRP were significantly associated with HOMA-IR. In conclusion, in a rural Chinese population, high intake of carbohydrate and low intake of fat and protein were associated with insulin resistance and hypertension, possibly by increasing inflammatory factors such as sICAM-1 and hsCRP, increasing BF% and increasing the level of plasma TG.

Impedance ratio: a novel marker and a powerful predictor of mortality in hemodialysis patients

PURPOSE

Impedance ratio (Imp-R) obtained by multifrequency bioimpedance analysis (BIA) has been shown to be associated with volume and nutrition status. In this prospective study, the predictive role of Imp-R for mortality in hemodialysis (HD) patients was investigated.

METHODS

Multifrequency (5-50-100-200 kHz) BIA was applied to 493 prevalent HD patients in March-April 2006. Imp-R was defined as the ratio of 200-5 kHz impedance values. Demographical, clinical and laboratory data at the time of the analysis were recorded. All-cause and cardiovascular (CV) mortality were assessed during 3 years of follow-up.

RESULTS

Mean age was 57.7 ± 13.9 years, HD duration 52.1 ± 42.6 months and prevalence of diabetes 21.7 %. Imp-R was negatively correlated with nutritional markers including albumin, creatinine and hemoglobin levels. In addition, there was a positive correlation between Imp-R and age, ratio of extracellular water to total body water and high-sensitive C-reactive protein. Over a mean follow-up period of 27.9 ± 11.1 months, 93 deaths (52 from CV reasons) were observed. In the multivariate analysis, Imp-R was significantly associated with all-cause and CV mortality after adjustments [HR 1.13, 95 % CI (1.04-1.23); p = 0.004 and HR 1.15, 95 % CI (1.03-1.27); p = 0.01, respectively]. The risk of all-cause mortality was 3.4 times higher in the fourth quartile of Imp-R (>83.5 %) compared to the first Imp-R quartile (<78.8 %) as reference. Cutoff value of Imp-R for all-cause mortality was 82.0 % with a sensitivity of 65.5 % and specificity of 64 %.

CONCLUSION

Impedance ratio measured by multifrequency in standardized conditions BIA is an independent and powerful predictor of both all-cause and CV mortality in hemodialysis patients.

Cathasept Line Lock and Microbial Colonization of Tunneled Hemodialysis Catheters: A Multicenter Randomized Controlled Trial

BACKGROUND

Catheter-related bloodstream infections (CRBSIs) cause morbidity and mortality in hemodialysis (HD) patients. Cathasept (tetra-sodium EDTA) solution has antimicrobial and anticoagulant activities.

STUDY DESIGN

Multicenter prospective randomized controlled study.

SETTING & PARTICIPANTS

117 maintenance HD patients with confirmed uncolonized tunneled HD catheters from 4 HD centers.

INTERVENTION

Patients were randomly assigned to receive Cathasept 4% locks (Cathasept group) or stayed with heparin 5,000 U/mL locks (heparin group), filled thrice weekly according to catheter lumen volume until the catheter was removed or for a maximum of 8 months.

OUTCOMES

Primary outcome was clinically significant microbial colonization of the catheter, defined as a through-catheter quantitative blood culture yielding ≥ 1,000 colony-forming units/mL of bacteria or yeast. Secondary outcomes included CRBSI rate, catheter patency, and biomarkers of inflammation and anemia.

MEASUREMENTS

Weekly through-catheter quantitative blood culture, high-sensitivity C-reactive protein fortnightly, and full blood count and ferritin monthly.

RESULTS

Incidence rates of catheter colonization were 0.14/1,000 catheter-days in the Cathasept group and 1.08/1,000 catheter-days in the heparin group (incidence rate ratio [IRR], 0.13; 95% CI, 0.003-0.94; P=0.02). CRBSI rates were 0.28/1,000 catheter-days in the Cathasept group and 0.68/1,000 catheter days in the heparin group (IRR, 0.40; 95% CI, 0.08-2.09; P=0.3). The proportion of dialysis sessions with achieved prescribed blood flow rate was significantly lower in the Cathasept group (66.8% vs 75.3%; P<0.001), with more patients requiring thrombolytic locks or infusions to maintain catheter patency (22 vs 9; P=0.01). Mean high-sensitivity C-reactive protein level was 11.6±5.3 (SE) mg/L lower for patients in the heparin group (P=0.03). Anemia marker levels were similar in both groups.

LIMITATIONS

Study was underpowered to assess effect on CRBSI, terminated early due to slow recruitment, and not double blinded.

CONCLUSIONS

Cathasept significantly reduced tunneled hemodialysis catheter colonization, but the reduction in CRBSIs was not statistically significant, and it was associated with more thrombotic complications. Its safety profile was comparable to heparin lock solution.

Exercise training for adults with chronic kidney disease

BACKGROUND

Chronic kidney disease (CKD) is a worldwide public health problem. In the National Kidney Foundation Disease Outcomes Quality Initiative guidelines it is stressed that lifestyle issues such as physical activity should be seen as cornerstones of the therapy. The physical fitness in adults with CKD is so reduced that it impinges on ability and capacity to perform activities in everyday life and occupational tasks. An increasing number of studies have been published regarding health effects of various regular exercise programmes in adults with CKD and in renal transplant patients.

OBJECTIVES

We aimed to: 1) assess the effects of regular exercise in adults with CKD and kidney transplant patients; and 2) determine how the exercise programme should be designed (e.g. type, duration, intensity, frequency of exercise) to be able to affect physical fitness and functioning, level of physical activity, cardiovascular dimensions, nutrition, lipids, glucose metabolism, systemic inflammation, muscle morphology and morphometrics, dropout rates, compliance, adverse events and mortality.

SEARCH STRATEGY

We searched the Cochrane Renal Group's specialised register, CENTRAL, MEDLINE, EMBASE, CINAHL, Web of Science, Biosis, Pedro, Amed, AgeLine, PsycINFO and KoreaMed. We also handsearched reference lists of review articles and included studies, conference proceeding's abstracts. There were no language restrictions.Date of last search: May 2010.

SELECTION CRITERIA

We included any randomised controlled trial (RCT) enrolling adults with CKD or kidney transplant recipients undergoing any type of physical exercise intervention undertaken for eight weeks or more. Studies using less than eight weeks exercise, those only recommending an increase in physical activity, and studies in which co-interventions are not applied or given to both groups were excluded.

DATA COLLECTION AND ANALYSIS

Data extraction and assessment of study and data quality were performed independently by the two authors. Continuous outcome data are presented as standardised mean difference (SMD) or mean difference (MD) with 95% confidence intervals (CI).

MAIN RESULTS

Forty-five studies, randomising 1863 participants were included in this review. Thirty two studies presented data that could be meta-analysed. Types of exercise training included cardiovascular training, mixed cardiovascular and resistance training, resistance-only training and yoga. Some studies used supervised exercise interventions and others used unsupervised interventions. Exercise intensity was classed as 'high' or 'low', duration of individual exercise sessions ranged from 20 minutes/session to 110 minutes/session, and study duration was from two to 18 months. Seventeen per cent of studies were classed as having an overall low risk of bias, 33% as moderate, and 49% as having a high risk of bias.The results shows that regular exercise significantly improved: 1) physical fitness (aerobic capacity, 24 studies, 847 participants: SMD -0.56, 95% CI -0.70 to -0.42; walking capacity, 7 studies, 191 participants: SMD -0.36, 95% CI-0.65 to -0.06); 2) cardiovascular dimensions (resting diastolic blood pressure, 11 studies, 419 participants: MD 2.32 mm Hg, 95% CI 0.59 to 4.05; resting systolic blood pressure, 9 studies, 347 participants: MD 6.08 mm Hg, 95% CI 2.15 to 10.12; heart rate, 11 studies, 229 participants: MD 6 bpm, 95% CI 10 to 2); 3) some nutritional parameters (albumin, 3 studies, 111 participants: MD -2.28 g/L, 95% CI -4.25 to -0.32; pre-albumin, 3 studies, 111 participants: MD - 44.02 mg/L, 95% CI -71.52 to -16.53; energy intake, 4 studies, 97 participants: SMD -0.47, 95% CI -0.88 to -0.05); and 4) health-related quality of life. Results also showed how exercise should be designed in order to optimise the effect. Other outcomes had insufficient evidence.

AUTHORS' CONCLUSIONS

There is evidence for significant beneficial effects of regular exercise on physical fitness, walking capacity, cardiovascular dimensions (e.g. blood pressure and heart rate), health-related quality of life and some nutritional parameters in adults with CKD. Other outcomes had insufficient evidence due to the lack of data from RCTs. The design of the exercise intervention causes difference in effect size and should be considered when prescribing exercise with the aim of affecting a certain outcome. Future RCTs should focus more on the effects of resistance training interventions or mixed cardiovascular- and resistance training as these exercise types have not been studied as much as cardiovascular exercise.

Influence of oxidative stress and inflammation on rHuEPO requirements of hemodialysis patients with CRP values "in normal range"

AIMS

We sought to evaluate influences of oxidative stress (OS) on rHuEPO requirements in hemodialysis patients without chronic inflammation.

METHODS

Sixty-eight hemodialysis patients and 46 healthy controls underwent measurements plasma levels of antioxidative agents, such as glutathione peroxidase (GPX), superoxide dismutase (SOD), and oxidative compounds including malonyldialdehyde (MDA). We retrospectively analyzed the last 3 months' rHuEPO requirements, iron indices, and CRP levels.

RESULTS

Plasma levels for SOD, GPX, and MDA were 974.4+/-216.4 U/gHb, 44.4+/-13.6 U/gHb, 10.0+/-2.0 nmol/mL, respectively yielding results that were different from healthy controls (P<.0001). Increased OS negatively correlated with hemoglobin levels (P<.0001) and positively correlated with rHuEPO requirements (P<.01). Increased antioxidative capacity positively correlated with hemoglobin levels (P<.0001) and negatively correlated with rHuEPO requirements (P<.0001). For further analyses, hemodialysis patients were subgrouped according to rHuEPO requirements as group I (lowest 1/3, n=23), group II (moderate 1/3, n=23) and group III (highest 1/3, n=22). Group III displayed the highest MDA (P<.05), the lowest SOD (P<.0001), and comparable GPX (P<.05) levels. Group III also had the highest CRP and the lowest albumin levels compared with the others (P<.01).

CONCLUSION

OS has strong adverse influences on rHuEPO responses of HD patients with "normal" CRP levels, but it should not be forgotten that CRP levels in the "normal" range may still reflect ongoing microinflammation.