A new nutritional risk index for predicting mortality in hemodialysis patients: Nationwide cohort study

Prognostic role of nutritional and inflammatory indicators for patient survival and death with functional graft in living kidney transplant recipients

BACKGROUND

The clinical importance of nutrition and inflammation in patients with end-stage renal disease is well established. In this study, we investigated the role of nutritional and inflammatory indicators in the patient outcomes of living donor kidney transplant recipients.

METHODS

We included 204 consecutive patients who underwent kidney transplantation at our institute between 2003 and 2022. We retrospectively reviewed medical charts to obtain clinical information. Six nutritional indicators and two inflammatory indicators were assessed. Patient outcomes were investigated, and predictive factors were explored.

RESULTS

The median patient age and follow-up period were 48 years and 99 months, respectively. The cohort included patients with preoperative malnutrition and microinflammation. No significant differences in graft survival were identified according to nutritional and inflammatory indicators, whereas the survival index, controlled nutritional status, and C-reactive protein levels were associated with patient survival. The survival index was an independent indicator of survival and death in patients with functioning grafts (P = 0.047 and P = 0.013, respectively). Furthermore, the C-reactive protein level could distinguish between low and high mortality risks in patients with good nutrition (P = 0.019).

CONCLUSIONS

Our findings suggest that nutrition and inflammation indicators play important roles in predicting outcomes in living donor kidney transplantation recipients. Further research is warranted to establish optimal management strategies.

Associations between bioelectrical impedance analysis-derived phase angle, protein-energy wasting and all-cause mortality in older patients undergoing haemodialysis

AIM

Protein-energy wasting (PEW) is a common syndrome in patients undergoing haemodialysis (HD) and is associated with poor prognosis. Bioelectrical impedance analysis (BIA)-derived phase angle (PA) is useful for predicting PEW, but sex and age need to be considered. We aimed to reveal sex-specific cut-off values of PA predicting PEW in HD patients aged ≥65.

METHODS

This two-centre retrospective cohort study included patients on HD who underwent BIA. PEW was detected using the International Society of Renal Nutrition and Metabolism (ISRNM) criteria as a reference. The PA was measured using a multifrequency bioimpedance device. Sex-specific cut-off values of PA predicting PEW were detected by receiver-operator characteristic analysis. We investigated the association between PEW determined using sex-specific cut-off values for PA and all-cause mortality.

RESULTS

This study included 274 patients undergoing HD, with a median age of 75 (70-80) years, mean PA of 3.8 ± 1.1° and PEW of 43%. Over a median follow-up duration of 1095 (400-1095) days, 111 patients died. Cut-off values of PA predicting PEW were as follows: female, 3.00° (sensitivity, 87.3%; specificity, 77.5%), and male, 3.84° (sensitivity, 77.6%; specificity, 71.4%). The kappa coefficient between sex-specific cut-off values of the PA and ISRNM criteria had a moderate coincidence level of 0.55. PEW detected by PA was independently associated with all-cause mortality (hazard ratio: 2.40; 95% confidence interval: 1.51-3.85; p < .001).

CONCLUSIONS

Sex-specific cut-off values for PA in older HD patients may be useful as a screening tool for predicting PEW and mortality.

Trends in clinical outcomes of older hemodialysis patients: data from the 2023 Korean Renal Data System (KORDS)

With an increasing aging population, the mean age of patients with end-stage kidney disease (ESKD) is globally increasing. However, the current clinical status of elderly patients undergoing hemodialysis (HD) is rarely reported in Korea. The current study analyzed the clinical features and trends of older patients undergoing HD from the Korean Renal Data System (KORDS) database. The patients were divided into three groups according to age: <65 years (the young group), n = 50,591 (35.9%); 65-74 years (the younger-old group), n = 37,525 (26.6%); and ≥75 years (the older-old group), n = 52,856 (37.5%). The proportion of older-old group undergoing HD significantly increased in incidence and decreased in prevalence from 2013 to 2022. The median levels of hemoglobin, serum creatinine, albumin, calcium, phosphorus, and intact parathyroid hormone significantly decreased in the older-old group. The proportions of arteriovenous fistula creation and left forearm placement showed decreased trends with age. Although the utilization of low surface area dialyzers increased with age, the dialysis adequacy, including urea reduction ratio and Kt/V was within acceptable range in the older-old group on HD. Over the past 20 years, the mortality rate in the older-old group has increased, with cardiovascular diseases decreasing and infectious diseases increasing. The incidence of elderly patients undergoing HD has increased over time, but the high mortality of the older-old group needs to be solved. Therefore, it is imperative to develop holistic strategies based on age and individual needs for patients with ESKD.

Impact of nutrition and inflammation indicators on peritoneal dialysis initiation and management

BACKGROUND

The clinical significance of nutrition and inflammation in dialysis patients is well established. This study aimed to evaluate the association between prognosis and indicators of nutrition and inflammation.

METHODS

A total of 253 consecutive patients who underwent peritoneal dialysis (PD) as primary renal replacement therapy at our institute between 2006 and 2021 were included. We retrospectively reviewed the patient's medical charts and obtained their clinical information. Nine nutritional and two inflammatory indicators were assessed. Patient outcomes were investigated, and predictive factors were explored.

RESULTS

The median age and follow-up period were 65 years and 54 months, respectively. Most nutritional indicators and C-reactive protein (CRP) levels showed a significant correlation with residual renal function. Multivariate analysis revealed that the survival index, nutritional risk index for Japanese hemodialysis patients, and CRP levels were independent indicators of patient survival (P < 0.001, P = 0.034, and P = 0.005, respectively) and cardiovascular disease-free survival (P = 0.009, P = 0.04, and P = 0.017, respectively). Patients with a survival index < 19 and CRP ≥ 0.5 had a high risk of mortality and cardiovascular death (P < 0.0001 and P = 0.0002, respectively).

CONCLUSIONS

Our findings suggest that indicators of nutrition and inflammation play important roles in predicting patient outcomes. Further research is warranted to establish optimal management strategies for patients on PD.

A simple score for malnutrition-inflammation complex syndrome (MICS) is associated with the risk of mortality in Japanese patients undergoing maintenance hemodialysis

INTRODUCTION

Malnutrition-inflammation complex syndrome (MICS) is highly prevalent in patients undergoing hemodialysis. We determined the prognostic value of the Simple MICS score, calculated using a combination of age, body mass index, and serum concentrations of albumin, creatinine, and C-reactive protein.

METHODS

We retrospectively recruited 218 Japanese patients undergoing maintenance hemodialysis. The primary outcome was all-cause mortality, and the main exposure was the Simple MICS score. Cox proportional hazard regression analysis and logistic regression analysis were used to characterize the relationship between the Simple MICS score and mortality.

RESULTS

During a median 4.4-year follow-up period, 56 patients died. Multivariable-adjusted models showed that a higher Simple MICS score was associated with higher risks of mortality. The predictability for all-cause mortality of the Simple MICS score was significantly better than conventional nutrition-related indices.

CONCLUSION

The Simple MICS score can be used to stratify mortality risk in patients undergoing maintenance hemodialysis.

Serum Myostatin at Dialysis Initiation May Predict 1-Year Mortality and Hospitalization

OBJECTIVE

Myostatin, which is known as a negative skeleton muscle regulator, is associated with mortality in maintenance hemodialysis patients. However, the significance of serum myostatin concentrations at dialysis initiation has not been established. We investigated the relation between serum myostatin concentrations and mortality or hospitalization within 1 year in incident dialysis patients.

METHODS

After a patient initiating hemodialysis or peritoneal dialysis during 2016-2018 was enrolled, the patient's serum myostatin at dialysis initiation was measured. Composite outcomes comprising mortality and hospitalization within 1 year after dialysis initiation were compared between two groups divided according to myostatin levels. The Cox proportional hazards model was used to assess significant relations between myostatin and outcomes.

RESULTS

This study examined 104 incident dialysis patients with a mean age of 65.5 ± 14.0 years (68% male). Kaplan-Meier analyses indicated the 1-year hospitalization-free and survival rate as significantly lower in the lower myostatin group than in the higher myostatin group (p = 0.0020). Cox proportional hazards regression analyses revealed that the value of myostatin logarithm at dialysis initiation was inversely associated with the occurrence of a composite outcome, independently of age (hazard ratio 0.16, 95% confidence interval: 0.05-0.57). Receiver operating characteristic analysis showed the area under the curve of serum myostatin for predicting death or hospitalization within 1 year as higher than those of clinical indices of nutritional disturbance and frailty.

CONCLUSION

Serum myostatin concentration at dialysis initiation is inversely associated with adverse outcomes in these dialysis-initiated patients.

Mortality risk factors among patients undergoing hemodialysis in a nursing home

AIM

This study aimed to verify the impact of low body mass index (BMI) on mortality in nursing home residents undergoing hemodialysis and to clarify other associated mortality risk factors.

METHODS

This retrospective study included patients admitted to a nursing home affiliated with Nagasaki Renal Center between April 2014 and March 2022. Medical data were collected on admission, and participants were divided into low and high BMI groups according to their median BMI values. The patients were followed up until March 2023. The association between survival and patient history was also analyzed.

RESULTS

Of the 106 patients (average age, 81.3 ± 7.9 years; male, 36.8%; median dialysis vintage, 32.5 [interquartile range (IQR), 13.8-79.3] months), 52 and 54 were classified into the low (median < 18.4 kg/m2 ) and high (≥18.4 kg/m2 ) BMI groups, respectively. Multivariable Cox proportional hazards analysis indicated that BMI (hazard ratio, 0.87; 95% confidence interval [CI]: 0.82-0.94; P < 0.001) was closely associated with survival. Multivariable logistic regression revealed that dementia was associated with low BMI (odds ratio: 2.89, 95% CI: 1.07-7.83, P = 0.03).

CONCLUSIONS

Low BMI was an important factor contributing to poor patient survival. Dementia was associated with low BMI. Therefore, the management of both nutrition and dementia is essential for nursing home residents undergoing hemodialysis. Geriatr Gerontol Int 2023; 23: 660-664.

The Effects of a Tailored Dietary Education Program for Older Adult Patients on Hemodialysis: A Preliminary Study

This study aimed to investigate the overall effects of a tailored dietary education program for older adult patients on hemodialysis (HD) based on self-efficacy theory, dietary knowledge and habits, nutritional intake, and biochemical parameters. A nonequivalent control group pre-test-post-test design was conducted for 8 weeks. The experimental and control groups received a weekly nutritional program and standard nursing care with an additional educational session, respectively. A clinical survey was conducted before and after the intervention. After the intervention, self-efficacy, dietary knowledge, and dietary habits were higher in the experimental group than in the control group. Moreover, carbohydrate, phosphorus, and sodium intake significantly decreased post-intervention in the experimental group but not in the control group. The dietary education program for older HD patients showed positive effects on boosting their self-efficacy, increasing dietary knowledge, improving dietary habits, and decreasing carbohydrate, calcium, phosphorus, and sodium intake.

Effect of nutritional supplementation on mortality in peritoneal dialysis patients: A meta-analysis

BACKGROUND

Malnutrition is a common clinical problem in peritoneal dialysis (PD) patients and is a predictor of mortality. This work analyzes the effect of nutritional supplementation for PD patients on all-cause and cardiovascular disease (CVD)-related deaths by meta-analysis.

METHODS

A study about nutritional interventions for PD patients on all-cause or CVD-related mortality is included.

RESULTS

Eight studies were included. The results showed that nutritional intervention can reduce all-cause mortality in PD patients (HR, 0.71; 95% confidence interval (CI), 0.64-0.79; p < 0.01). In CVD-related mortality, the results also showed that nutritional interventions significantly reduce CVD-related mortality (HR, 0.75; 95% CI, 0.64-0.87; p < 0.01). In exploratory analysis, vitamin D, folic acid, and high-plant-protein ratio intake have relative advantages.

CONCLUSION

Appropriate nutritional supplementation to PD patients can effectively reduce all-cause and CVD- related mortality in clinical practice, especially for vitamin D, folic acid, sodium supplements, and a high proportion of plant protein.

The implication of calf circumference and grip strength in osteoporosis and bone mineral density among hemodialysis patients

BACKGROUND

Chronic kidney disease-mineral and bone disorder (CKD-MBD), nutritional status, and uremia management have been emphasized for bone management in hemodialysis patients. Nevertheless, valuable data on the importance of muscle mass in bone management are limited, including whether conventional management alone can prevent osteoporosis. Thus, the importance of muscle mass and strength, independent of the conventional management in osteoporosis prevention among hemodialysis patients, was evaluated.

METHODS

Patients with a history of hemodialysis 6 months or longer were selected. We assessed the risk for osteoporosis associated with calf circumference or grip strength using multivariable adjustment for indices of CKD-MBD, nutrition, and dialysis adequacy. Moreover, the associations between bone mineral density (BMD), calf circumference, grip strength, and bone metabolic markers were also evaluated.

RESULTS

A total of 136 patients were included. The odds ratios (95% confidence interval) for osteoporosis at the femoral neck were 1.25 (1.04-1.54, P < 0.05) and 1.08 (1.00-1.18, P < 0.05) per 1 cm shorter calf circumference or 1 kg weaker grip strength, respectively. Shorter calf circumference was significantly associated with a lower BMD at the femoral neck and lumbar spine (P < 0.001). Weaker grip strength was also associated with lower BMD at the femoral neck (P < 0.01). Calf circumference or grip strength was negatively correlated with bone metabolic marker values.

CONCLUSION

Shorter calf circumference or weaker grip strength was associated with osteoporosis risk and lower BMD among hemodialysis patients, independent of the conventional therapies.

Recent Advances in the Nutritional Screening, Assessment, and Treatment of Japanese Patients on Hemodialysis

Patients on hemodialysis (HD) have a higher rate of protein-energy wasting (PEW) due to lower dietary intake of energy and protein (particularly on dialysis days) and greater loss of many nutrients in the dialysate effluent than other patients. The most well-known method of nutritional screening is the subjective global assessment. Moreover, the Global Leadership Initiative on MalnutIrition has developed the first internationally standardized method for diagnosing malnutrition; however, its use in patients on HD has not been established. In contrast, the nutritional risk index for Japanese patients on HD has recently been developed as a screening tool for malnutrition in patients on HD, based on the modified PEW criteria. These tools are beneficial for screening nutritional disorders, enabling registered dietitians to assess patients' dietary intake on dialysis and non-dialysis days and provide advice on dietary intake, especially immediately after dialysis cessation. Oral supplementation with enteral nutrients containing whey protein may also be administered when needed. In patients that experience adverse effects from oral supplementation, intradialytic parenteral nutrition (IDPN) should be combined with moderate dietary intake because IDPN alone cannot provide sufficient nutrition.

Early detection of thiamine deficiency by non-thyroidal illness syndrome in a hemodialysis patient

An 88-year-old male patient on maintenance hemodialysis (HD) therapy experienced gradual losses in appetite and liveliness during the course of 1 month. Physical examinations revealed no abnormalities. However, blood testing indicated non-thyroidal illness syndrome (NTIS) typically observed in patients with severe illness, with serum levels of thyroid stimulating hormone, free triiodothyronine, and free thyroxine of 0.17 μIU/mL, < 1.0 pg/mL, and 0.23 ng/dL, respectively. Brain magnetic resonance imaging to exclude the possibility of central hypothyroidism unexpectedly displayed slight abnormalities inside of the thalami that were characteristic of Wernicke's encephalopathy. Additional examination disclosed low serum thiamine of 20 ng/mL. Thiamine injections of 100 mg at every HD treatment rapidly restored his appetite, liveliness, and NTIS findings. HD patients are at a particularly high risk of thiamine deficiency (TD) and associated severe symptoms due to losses of thiamine during HD sessions. However, its non-specific initial symptoms, including decreases in appetite and liveliness, as well as undetectability in routine blood tests complicate early detection, resulting in underdiagnosis and more severe outcomes. In the present case, TD manifested only as non-specific symptoms and was ultimately revealed by the presence of NTIS, which was resolved with thiamine supplementation. Thus, NTIS might assist in the early detection of TD as an initial sign in HD patients.

Importance of feeding status evaluation in older patients undergoing hemodialysis

Older hospitalized patients undergoing hemodialysis are increasingly experiencing malnutrition caused by dysphagia. However, only a few studies have focused on this problem. We used the Kuchikara Taberu Balance Chart (KTBC) to evaluate the patients' feeding status and examined its association with their nutritional status and prognosis. This study included elderly patients undergoing hemodialysis who were hospitalized at Nagasaki Renal Center for > 3 days between June 2021 and February 2022. In total, 82 inpatients were included [mean age, 73.4 ± 10.0 years; men, 57.3%; median dialysis vintage, 79.0 months (interquartile range, 37.3-164.8)]. We classified patients with lower than the median KTBC score (57 points) as being at risk for dysphagia; 37 patients (45.1%) were at risk for dysphagia. Spearman's rank correlation coefficient (ρ) elucidated that the KTBC total score was significantly associated with each nutritional indicator [serum albumin level (ρ = 0.505, p < 0.001); geriatric nutritional risk index (ρ = 0.600, p < 0.001); and nutritional risk index (ρ = -0.566, p < 0.001)]. The KTBC score was also closely associated with the body mass index (ρ = 0.228, p = 0.04). Patients with a lower KTBC score showed poor prognosis (log-rank test: p = 0.001), and age- and sex-adjusted Cox proportional analysis showed that the KTBC score was associated with life prognosis (hazard ratio, 0.90; 95% confidential interval, 0.86-0.94; p < 0.001). Therefore, we concluded that the patients at risk of dysphagia, identified using the KTBC score, were malnourished and had a poor prognosis. Hence, the evaluation of dysphagia using the KTBC is encouraged to prevent malnutrition in vulnerable older patients undergoing hemodialysis.

Utility of a modified Controlling Nutritional Status score in mortality risk assessment of patients on hemodialysis

PURPOSE

Malnutrition is common among hemodialysis patients. A nutritional index may be important for their prognosis prediction. We examined the use of a modified version of the Controlling Nutritional Status (CONUT) score as a predictor of mortality in hemodialysis patients and investigated whether statin use modified the association.

METHODS

We conducted a retrospective cohort study in 1130 adults (mean age 67.7 years, 35.0% women) on maintenance hemodialysis at four outpatient dialysis clinics in Japan. The exposure of interest was modified CONUT scores calculated by one-time data of serum albumin and total cholesterol at baseline, or mean data of these measures using multiple blood test results. The primary outcome was all-cause mortality. We examined the association between modified CONUT groups (low-risk, middle-risk, and high-risk) and mortality using multivariate Cox proportional hazard regression and logistic regression models in overall patients and by statin use.

RESULTS

During a median follow-up of 6.6 years, 525 (46.5%) patients died. Analysis using both one-time and mean data showed increased mortality risk in the high-risk modified CONUT score group as compared to the low-risk group (mean data: HR 2.52, 95% CI 1.96, 3.24); when stratified by statin use, the effect appeared stronger among users (mean data: HR 5.84, 95% CI 2.98, 11.44). Strong predictive ability was observed, particularly for mortality risk at 5 year follow-up using mean data (AUC = 0.842).

CONCLUSION

Our results suggest that the modified CONUT score may be useful in helping clinicians quickly identify hemodialysis patients with poorer prognosis who may benefit from close monitoring and interventions.

Fluid Overload and Tissue Sodium Accumulation as Main Drivers of Protein Energy Malnutrition in Dialysis Patients

Protein energy malnutrition is recognized as a leading cause of morbidity and mortality in dialysis patients. Protein-energy-wasting process is observed in about 45% of the dialysis population using common biomarkers worldwide. Although several factors are implicated in protein energy wasting, inflammation and oxidative stress mechanisms play a central role in this pathogenic process. In this in-depth review, we analyzed the implication of sodium and water accumulation, as well as the role of fluid overload and fluid management, as major contributors to protein-energy-wasting process. Fluid overload and fluid depletion mimic a tide up and down phenomenon that contributes to inducing hypercatabolism and stimulates oxidation phosphorylation mechanisms at the cellular level in particular muscles. This endogenous metabolic water production may contribute to hyponatremia. In addition, salt tissue accumulation likely contributes to hypercatabolic state through locally inflammatory and immune-mediated mechanisms but also contributes to the perturbation of hormone receptors (i.e., insulin or growth hormone resistance). It is time to act more precisely on sodium and fluid imbalance to mitigate both nutritional and cardiovascular risks. Personalized management of sodium and fluid, using available tools including sodium management tool, has the potential to more adequately restore sodium and water homeostasis and to improve nutritional status and outcomes of dialysis patients.

Intradialytic parenteral nutrition using a standard amino acid solution not for renal failure in maintenance hemodialysis patients with malnutrition: a multicenter pilot study

Background

Standard amino acid solutions have recently been removed from the contraindications for use in dialysis patients in Japan. However, the details of their safety and efficacy in these patients are still not known. In this study, we investigated the safety and efficacy of intradialytic parenteral nutrition (IDPN) using ENEFLUID® injection containing standard amino acids, glucose, electrolytes, fats, and water-soluble vitamins in maintenance hemodialysis patients with malnutrition.

Methods

This clinical trial was designed as a multicenter, prospective, non-randomized, open-label, single-arm, observational pilot study. The participants were patients on maintenance hemodialysis who were in the nutritional high-risk group according to the Nutritional Risk Index for Japanese Hemodialysis Patients. One bag of ENEFLUID® injection was administered during every hemodialysis session for 12 weeks. The primary endpoint was change in serum transthyretin levels between before and after the 12-week period. As safety endpoints, we evaluated changes in body fluid volume and blood biochemical tests, including blood urea nitrogen and electrolytes, as well as blood glucose variability using flash glucose monitoring (FGM).

Results

The mean age and body mass index of the 13 participants were 79.0 ± 10.7 years and 18.0 ± 1.7 kg/m2, respectively. No significant changes were observed in nutritional parameters, including serum transthyretin, between before and after the start of the study. After IDPN initiation, there was no obvious fluid overload or significant changes in blood biochemical tests, including electrolytes, and the treatment could be safely continued for 12 weeks. In the FGM analysis, asymptomatic hypoglycemia during hemodialysis was observed at the beginning of the study, but there was a trend toward improvement after 12 weeks (area over the curve < 70 mg/dl per dialysis session: 747.5 ± 1333.9 to 21.6 ± 54.3, P = 0.09).

Conclusions

IDPN using ENEFLUID® injection can be safely continued, although it does not significantly improve markers of nutritional status. It also showed the potential to ameliorate asymptomatic hypoglycemia during hemodialysis sessions. More detailed studies of the improvement in nutritional indicators are needed.

Trial registration: This study was registered with the University Hospital Medical Information Network-Clinical Trials Registry (UMIN-CTR) on May 9, 2021 (registration ID, UMIN000044051).

Association of the nutritional risk index for Japanese hemodialysis with mortality and dietary nutritional intake in patients undergoing hemodialysis during long-term hospitalization

AIM

The nutritional risk index for Japanese hemodialysis (NRI-JH) is a nutritional screening tool for predicting mortality in patients undergoing hemodialysis; however, its utility in patients undergoing hemodialysis during long-term hospitalization who have a high risk of protein-energy wasting, is unclear.

METHODS

This retrospective study assessed hospitalized patients undergoing hemodialysis during long-term care at a single hospital. The NRI-JH was calculated using body mass index, serum albumin level, total cholesterol level, and serum creatinine level. The patients were categorized into three risk groups-low, medium, and high. Dietary energy and protein intake were evaluated by dietitians. The association of NRI-JH risk with nutritional intake and mortality were examined.

RESULTS

In total, 133 patients were analyzed. The NRI-JH risk was low in 24%, medium in 26%, and high in 50% of the patients. The patients in the high-risk group were older and had lower energy and protein intakes than those in the low- and medium-risk groups. High-risk patients showed shorter survival times than low- and medium-risk patients, and a high NRI-JH risk was associated with a high mortality rate (hazard ratio [HR], 2.12; 95% confidence interval [CI], 1.08-4.77; p < 0.05). The association weakened when protein intake and C-reactive protein level were added as covariates (HR, 2.01; 95% CI, 0.95-4.28, p = 0.07).

CONCLUSIONS

High NRI-JH risk was associated with low dietary nutritional intake and poor survival in patients undergoing hemodialysis during long-term hospitalization. Nutritional status evaluation and nutritional interventions may improve prognosis in this population.

Endocrine manifestations of chronic kidney disease and their evolving management: A systematic review

BACKGROUND

Chronic Kidney Disease (CKD) shows a wide range of renal abnormalities including the excretory, metabolic, endocrine, and homeostatic function of the kidney. The prognostic impact of the 'endocrine manifestations' which are often overlooked by clinicians cannot be overstated.

METHODS AND OBJECTIVES

A systematic review was attempted to provide a comprehensive overview of all endocrine abnormalities of CKD and their evolving principles of management, searching databases of PubMed, Embase, and Scopus and covering the literature between 2002 and 2022.

RESULTS

The endocrine derangements in CKD can be attributed to a myriad of pathologic processes, in particular decreased clearance, impaired endogenous hormone production, uremia-induced cellular dysfunction, and activation of systemic inflammatory pathways. The major disorders include anemia, hyperprolactinemia, insulin resistance, reproductive hormone deficiency, thyroid hormone deficiency, and serum FGF (Fibroblast Growth Factor) alteration. Long-term effects of CKD also include malnutrition and increased cardiovascular risk. The recent times have unveiled their detailed pathogenesis and have seen an evolution in the principles of management which necessitates a revision of current guidelines.

CONCLUSION

Increased advertence regarding the pathology, impact, and management of these endocrine derangements can help in reducing morbidity as well as mortality in the CKD patients by allowing prompt individualized treatment. Moreover, with timely and appropriate intervention, a long-term reduction in complications, as well as an enhanced quality of life, can be achieved in patients with CKD.

The Geriatric Nutritional Risk Index Is an Independent Predictor of Adverse Outcomes for Total Joint Arthroplasty Patients

BACKGROUND

Malnutrition affects patient outcomes after total joint arthroplasty (TJA). Although hypoalbuminemia has been used as a surrogate, there is no unanimous method for screening and assessing malnutrition. This study aimed to determine if malnutrition, as defined by the Geriatric Nutritional Risk Index (GNRI), is independently correlated with short-term (<30 days) postoperative complications and prognosis in patients undergoing TJA.

METHODS

The 2016-2019 American College of Surgeons National Surgical Quality Improvement Program was queried for all patients aged >65 years who underwent TJA. Based on GNRI value, patients were divided into 3 groups: normal nutrition (GNRI >98), moderate malnutrition (GNRI 92-98), and severe malnutrition (GNRI <92). After adjusting for potential confounders, multivariable regression models were used to analyze the association between GNRI and patient outcomes.

RESULTS

A total of 191,087 patients were included in the study. Prevalence of malnutrition based on body mass index (<18.5 kg/m²), albumin (<3.5 mg/dL), and GNRI (≤98) was 0.41% (784), 4.17% (7975), and 15.83% (30,258). Adjusted analysis showed that compared with normal nutrition, moderate and severe malnutrition status were associated with a higher rate of transfusion, readmission, and postoperative length of stay over 8 days (P < .05). Severe malnutrition was also associated with pneumonia, surgical site infection, urinary tract infection, sepsis, and revision surgery (P < .05).

CONCLUSION

Malnutrition, as defined by GNRI, is an independent predictor of adverse outcomes after TJA, including 30-day readmission, revision surgery, and increased length of stay. GNRI can be used to routinely screen and assess patient nutritional status before TJA and counsel patients and families appropriately.

LEVEL OF EVIDENCE

Level 3: Retrospective Cohort Study.

An equation to predict peak heart rate for prescribing exercise intensity in middle-aged to older patients requiring hemodialysis

PURPOSE

Exercise prescription based on a population-specific physiological response can help ensure safe and effective physical interventions. However, as a facile approach for exercise prescription in hemodialysis population that is based on their exercise capacity has not yet been established, the aim of our study was to develop a unique prediction formula for peak heart rate (HR) that can be used in this population.

METHODS

This cross-sectional study measured physical function and HR at peak exercise and anaerobic threshold (AT) during cardiopulmonary exercise tests in 126 individuals. Participants were randomly assigned to the development group (n = 78), whose data were used to calculate the prediction equation, or the validation group (n = 48).

RESULTS

The HR reserve in this population was significantly lower (0.44 ± 0.20%) and there was a large discrepancy between conventional age-predicted maximal HR and measured peak-HR values (R = 0.36). The average of the ratio between HR at AT point and peak HR was 85% (95% CI, 83.5%-86.4%). The peak-HR prediction equation was based on resting HR, presence of diabetes, physical dysfunction (gait speed < 1.0 m/s), and hypoalbuminemia (< 3.5 g/dL). It showed high prediction accuracy (R² [95%CI] = 0.71 [0.70-0.71]) with similar correlation coefficients between the development and validation groups (R = 0.82).

CONCLUSION

Aerobic exercise based on estimated peak HR < 85% obtained from the equation in this study may enable safe and effective physical intervention in this population.

The association between body mass index and all-cause mortality in Japanese patients with incident hemodialysis

Background

A higher body mass index (BMI) has been associated with better survival among chronic kidney disease patients in some reports. However, more research is required to determine the associations between BMI and mortality in incident hemodialysis patients. Therefore, this study aimed to investigate the association between mortality and BMI measured at the first hemodialysis session and 2 weeks after hemodialysis initiation in Japanese patients with incident hemodialysis.

Methods

We retrospectively enrolled 266 adult patients with incident hemodialysis who were treated at our hospital between May 2013 and June 2019. The data on BMI was obtained at the first hemodialysis session and 2 weeks after hemodialysis initiation. Patients were divided into tertiles based on BMI [<18.5 (low), 18.5–23.9 (normal), and ≥24 (high) kg/m2]. The normal group was used as the reference group. The primary outcome was all-cause mortality.

Results

The mean age of patient was 68.9 ± 12.0 years, and the BMI was 23.3 ± 4.24 kg/m2 at the first hemodialysis session. The body mass index was 22.0 ± 3.80 kg/m2 at 2 weeks after hemodialysis initiation. During a mean follow-up of 3.89 ± 2.12 years, 80 (30.1%) deaths occurred. In multivariate analyses, low BMI at the first hemodialysis session was significantly associated with worse all-cause mortality (hazard ratio, 2.39; 95% confidence interval, 1.13–5.03). At 2 weeks after hemodialysis initiation, high BMI was significantly associated with better all-cause mortality (hazard ratio, 0.38; 95% confidence interval, 0.18–0.81).

Conclusion

At 2 weeks after HD initiation, high BMI was associated with lower mortality in Japanese patients with incident hemodialysis.

Nutritional Status Association With Sarcopenia in Patients Undergoing Maintenance Hemodialysis Assessed by Nutritional Risk Index

Background

Malnutrition and sarcopenia are frequently observed in patients undergoing maintenance hemodialysis (MHD). To elucidate whether malnutrition is associated with sarcopenia in those cases, the relationship of nutritional status with sarcopenia was investigated.

Methods

Nutritional status was assessed using a nutritional risk index (NRI) developed for patients undergoing MHD. This retrospective cross-sectional study included 315 MHD patients (199 males, 116 females), who were divided into low-risk (score 0–7) and medium-/high-risk (score 8–13) groups. Sarcopenia and severe sarcopenia, along with low muscle mass, low muscle strength, and low physical performance were defined using the Asian Working Group for Sarcopenia 2019 criteria.

Results

The median NRI score was 5.0, while the prevalence of medium-/high-risk cases among the patients was 31.1%. Additionally, the rates of those with low muscle mass, low muscle strength, and low physical performance were 55.9, 60.6, and 31.4%, respectively, while those of sarcopenia and severe sarcopenia were 44.1 and 20.0%, respectively. Multivariable logistic regression analyses revealed a significant (P < 0.001) association of NRI score with sarcopenia [odds ratio (OR) 1.255, 95% confidence interval (CI) 1.143–1.377] and severe sarcopenia (OR 1.257, 95% CI 1.122–1.407), as well as low muscle mass (OR 1.260, 95% CI 1.157–1.374), low muscle strength (OR 1.310, 95% CI 1.178–1.457), and low physical performance (OR 1.216, 95% CI 1.104–1.339). Furthermore, medium-/high-risk status showed a significant (P < 0.05) association with sarcopenia (OR 2.960, 95% CI 1.623–5.401) and severe sarcopenia (OR 2.241, 95% CI 1.151–4.362), as well as low muscle mass (OR 2.141, 95% CI 1.219–3.760), low muscle strength (OR 7.665, 95% CI 3.438–17.091), and low physical performance (OR 2.570, 95% CI 1.401–4.716).

Conclusions

These results suggest that malnutrition contributes to sarcopenia/severe sarcopenia in MHD patients by reducing muscle mass and strength, and physical performance.

Emerging cross-talks between chronic kidney disease-mineral and bone disorder (CKD-MBD) and malnutrition-inflammation complex syndrome (MICS) in patients receiving dialysis

Chronic kidney disease–mineral and bone disorder (CKD–MBD) is a systemic disorder that affects multiple organs and systems and increases the risk of morbidity and mortality in patients with CKD, especially those receiving dialysis therapy. CKD–MBD is highly prevalent in CKD patients, and its treatment is gaining attention from healthcare providers who manage these patients. Additional important pathologies often observed in CKD patients are chronic inflammation and malnutrition/protein-energy wasting (PEW). These two pathologies coexist to form a vicious cycle that accelerates the progression of various other pathologies in CKD patients. This concept is integrated into the term “malnutrition–inflammation–atherosclerosis syndrome” or “malnutrition–inflammation complex syndrome (MICS)”. Recent basic and clinical studies have shown that CKD–MBD directly induces inflammation as well as malnutrition/PEW. Indeed, higher circulating levels of inorganic phosphate, fibroblast growth factor 23, parathyroid hormone, and calciprotein particles, as markers for critical components and effectors of CKD–MBD, were shown to directly induce inflammatory responses, thereby leading to malnutrition/PEW, cardiovascular diseases, and clinically relevant complications. In this short review, we discuss the close interplay between CKD–MBD and MICS and emphasize the significance of simultaneous control of these two seemingly distinct pathologies in patients with CKD, especially those receiving dialysis therapy, for better management of the CKD/hemodialysis population.

Utility of CHA2DS2-VASc Score to Predict Mid-Term Clinical Outcomes in Hemodialysis Patients

BACKGROUND

The CHA2DS2-VASc score has been widely used to predict stroke in patients with atrial fibrillation (AF). Recently, it was reported that the CHA2DS2-VASc score helps predict cardiovascular disease (CVD) or all-cause mortality in patients with or without AF. However, few reports have examined the association between this score and mortality in hemodialysis (HD) patients.

METHODS

We analyzed 557 consecutive patients who initiated HD at our facilities between February 2005 and October 2017. The CHA2DS2-VASc score was calculated at the time of initiation of HD. Patients were then categorized into three groups according to their CHA2DS2-VASc scores: 0-1 (low), 2-3 (intermediate), and 4-9 (high). Multivariate Cox proportional hazards analysis was used to assess independent risk factors for 3-year all-cause mortality.

RESULTS

During the 3-year follow-up period, 153 (27.5%) patients died (cardiovascular death: n = 88). According to multivariate analysis, serum albumin (hazard ratio [HR] 0.60, 95% confidence interval [CI] 0.43-0.85, p = 0.003), creatinine (HR 0.91, 95% CI 0.84-0.99, p = 0.049), and CHA2DS2-VASc score (HR 1.33, 95% CI 1.20-1.46, p < 0.001) were associated with 3-year all-cause mortality. Compared with patients in the low CHA2DS2-VASc score group, those in the intermediate- and high-score groups had a higher risk for all-cause and CVD mortality (all-cause mortality: HR 1.77, 95% CI 1.23-2.55, p = 0.002 and HR 2.94, 95% CI 1.90-4.53, p < 0.001, respectively; CVD mortality: HR 1.82, 95% CI 1.27-2.59, p = 0.001 and HR 2.85, 95% CI 1.88-4.31, p < 0.001, respectively).

CONCLUSION

The CHA2DS2-VASc score is a valuable predictor of 3-year all-cause and CVD mortality in incident HD patients.

Differentiation of Nutritional Risk among Polish Seniors Based on Selected Lifestyle Characteristics

Elderly people living in the community are a population group at high nutritional risk. The aim of this study was to assess the nutritional risk of Polish seniors in relation to the region of residence and selected lifestyle characteristics (alcohol consumption, smoking, sleep, physical activity). The SCREEN-14 (Seniors in the Community: Risk Evaluation for Eating and Nutrition) questionnaire was used to assess nutritional risk. The questionnaire was conducted among 320 Polish adults aged 60 and older. The snowball method was used to select the sample. The study was conducted from May to July 2021 in two regions. Cluster analysis with agglomeration technique was used to identify the association between categories of variables describing nutritional risk level, demographic characteristics, and lifestyle characteristics. Logistic regression analysis was used to assess the association between identified nutritional risk levels and selected lifestyle characteristics. Men over 75 and seniors living in smaller towns have been shown to be at higher nutritional risk. High nutritional risk was significantly more common among those who consumed alcohol, smoked tobacco, and had less than six hours or more than nine hours of sleep per day. In addition, low to moderate physical activity was associated with higher nutritional risk. The identification of factors that increase nutritional risk among seniors can support the planning of ways to prevent nutritional problems in this age group.

Association between the psoas muscle index and hospitalization for pneumonia in patients undergoing hemodialysis

Background

Although muscle mass loss and pneumonia are common and crucial issues in hemodialysis (HD) patients, few reports have focused on their association, which remains unclear. This study assessed the association between skeletal muscle mass and the incidence of pneumonia in HD patients using the psoas muscle index (PMI).

Methods

This retrospective study included 330 patients on HD who were treated at a single center between July 2011 and June 2012. The observation period was between July 2011 and June 2021. Demographic, clinical, and HD data were collected, and the associations between PMI and hospitalization due to bacterial pneumonia were evaluated using Cox proportional hazards models adjusted for patients’ background data. Additionally, the correlation between patient characteristics and PMI was evaluated using multivariable linear regression.

Results

Among 330 patients (mean age, 67.3 ± 13.3; 56.7% male; median dialysis vintage 58 months, (interquartile range [IQR] 23–124), 79 were hospitalized for pneumonia during the observation period (median observation period was 4.5 years [IQR 2.0–9.1]). The multivariable Cox proportional analysis, which was adjusted for age, sex, dialysis vintage, diabetes mellitus, and stroke history and considered death as a competing risk, indicated that decreased PMI/(standard deviation) was closely associated with the development of pneumonia (hazard ratio: 0.67, 95% confidence interval: 0.47–0.95, p = 0.03).

Conclusions

Skeletal muscle mass was associated with the development of pneumonia in patients on HD and could be a useful marker for the risk of pneumonia.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12882-021-02612-7.

Utility of Geriatric Nutritional Risk Index in Patients with Chronic Kidney Disease: A Mini-Review

Chronic kidney disease (CKD) is one of the most significant risk factors for cardiovasculardisese. Malnutrition has been recognized as a significant risk factor for cardiovascular disease in patients with CKD, including those on chronic dialysis. Current studies showed higher all-cause and cardiovascular mortality rates in patients with CKD and malnutrition. Geriatric nutritional risk index (GNRI), a simple and validated nutritional screening measure for both elderly people and patients on dialysis, is based only on three objective parameters: body weight, height, and serum albumin level. Recently, we demonstrated that the cutoff GNRI for predicting all-cause and cardiovascular mortality was 96 in patients on hemodialysis. Moreover, together with left ventricular hypertrophy and low estimated glomerular filtration rate, the utility of GNRI as a significant determinant of cardiovascular events was demonstrated in non-dialysis-dependent patients with CKD. In the present review, we summarize available evidence regarding the relationship of GNRI with all-cause and cardiovascular mortality in patients with CKD including those on dialysis.

Dialyzer surface area is a significant predictor of mortality in patients on hemodialysis: a 3-year nationwide cohort study

A target Kt/V of > 1.4 and use of a high-flux dialyzer are recommended for patients on hemodialysis. However, there is little information on the relationship between the dialyzer surface area and mortality in these patients. In this nationwide cohort study, we aimed to clarify this relationship by analyzing data from the Japanese Society for Dialysis Therapy for 2010–2013. We enrolled 234,638 patients on hemodialysis who were divided according to quartile for dialyzer surface area into the S group (small, < 1.5 m²), M group (medium, 1.5 m²), L group (large, 1.6 to < 2.0 m²), or XL group (extra-large, ≥ 2.0 m²). We assessed the association of each group with 3-year mortality using Cox proportional hazards models and performed propensity score matching analysis. By the end of 2013, a total of 53,836 patients on dialysis (22.9%) had died. There was a significant decrease in mortality with larger dialyzer surface areas. The hazard ratio (95% confidence interval) was significantly higher in the S group (1.15 [1.12–1.19], P < 0.0001) and significantly lower in the L group (0.89 [0.87–0.92] P < 0.0001) and XL group (0.75 [0.72–0.78], P < 0.0001) than in the M group as a reference after adjustment for all confounders. Findings were robust in several sensitivity analyses. Furthermore, the findings remained significant after propensity score matching. Hemodialysis using dialyzers, especially super high-flux dialyzers with a larger surface area might reduce mortality rates, and a surface area of ≥ 2.0 m² is superior, even with the same Kt/V.

Association of the nutritional risk index for Japanese hemodialysis patients with long-term mortality: The Q-Cohort Study

BACKGROUND

Protein-energy wasting (PEW) is a risk factor for mortality in patients undergoing hemodialysis. Recently, a nutritional risk index for Japanese hemodialysis patients (NRI-JH) has been proposed as a surrogate index of PEW. However, no study has determined the association of the NRI-JH with long-term mortality in patients undergoing hemodialysis. Furthermore, the validity of the NRI-JH has not been confirmed.

METHODS

In total, 3046 patients undergoing hemodialysis and registered in the Q-Cohort Study were followed up for 10 years. The NRI-JH was calculated on the basis of body mass index and serum levels of albumin, total cholesterol, and creatinine. The patients were divided into four groups according to the NRI-JH scores: 0-3 (G1, n = 1343), 4-7 (G2, n = 1136), 8-10 (G3, n = 321), and 11-13 (G4, n = 246). We examined the association between the NRI-JH and the 4-year and 10-year risks of all-cause, cardiovascular, and infection-related deaths using the Cox proportional hazards model.

RESULTS

During the follow-up period, 647 patients died during the first 4 years, and 1503 patients died within 10 years. The 4-year prognosis was analyzed and compared with the lowest NRI-JH score group. Multivariable-adjusted hazard ratios (95% confidence intervals) for all-cause death were 1.93 (1.57-2.38), 2.68 (2.05-3.50), and 3.16 (2.40-4.16) in the G2, G3, and G4 groups, respectively. Similarly, a higher NRI-JH score was associated with an increased risk of cardiovascular and infection-related deaths.

CONCLUSION

A higher NRI-JH score was associated with an increased risk of long-term mortality in patients undergoing maintenance hemodialysis.

TRIAL REGISTRATION

The study protocol was registered in the University Hospital Medical Information Network (UMIN) clinical trial registry (UMIN ID: 000000556).

Usual nutritional scores have acceptable sensitivity and specificity for diagnosing malnutrition compared to GLIM criteria in hemodialysis patients

Diagnosing malnutrition by the recently published Global Leadership Initiative on Malnutrition (GLIM) criteria requires using modern techniques for body composition measurements. We hypothesized that the prevalence of malnutrition identified by usual nutritional scores and according to GLIM criteria may be close to each other due to the number of components shared between them. Our aim was to compare the concurrent validity of four nutritional scores, malnutrition-inflammation score (MIS), objective score of nutrition on dialysis, geriatric nutritional index (GNRI), and nutritional risk index against the GLIM criteria for malnutrition in maintenance hemodialysis patients. This prospective observational study was performed on 318 maintenance hemodialysis outpatients (37% women) with a mean age of 68.7 ± 13.1 years and a median dialysis vintage of 21 months. According to the GLIM criteria, 45.9% of these patients were diagnosed with malnutrition. Nutritional scores, dietary intake and body composition parameters were measured. All nutritional scores showed a strong association with malnutrition in multivariable logistic regression models. In discriminating the nutritional risk, the ROC AUC was largest for GNRI (0.70, 95% CI: 0.65-0.75; P< .001). Nutritional risk index and MIS showed high specificity but lower sensitivity compared to GNRI and objective score of nutrition on dialysis. Compared to MIS, GNRI had better concurrent validity (higher sensitivity and acceptable specificity) but was inferior to MIS in terms of relation to certain etiologic and phenotypic components of the GLIM criteria (specifically, to dietary intake and decrease in dry weight). In summary, of the nutritional scores tested, GNRI is the most sensitive score in identifying malnutrition diagnosed by GLIM criteria, but MIS is more specific and better in predicting the individual components of the GLIM criteria.

Methods and Nutritional Interventions to Improve the Nutritional Status of Dialysis Patients in JAPAN-A Narrative Review

Patients receiving dialysis therapy often have frailty, protein energy wasting, and sarcopenia. However, medical staff in Japan, except for registered dietitians, do not receive training in nutritional management at school or on the job. Moreover, registered dietitians work separately from patients and medical staff even inside a hospital, and there are many medical institutions that do not have registered dietitians. In such institutions, medical staff are required to manage patients' nutritional disorders without assistance from a specialist. Recent studies have shown that salt intake should not be restricted under conditions of low nutrition in frail subjects or those undergoing dialysis, and protein consumption should be targeted at 0.9 to 1.2 g/kg/day. The Japanese Society of Dialysis Therapy suggests that the Nutritional Risk Index-Japanese Hemodialysis (NRI-JH) is a useful tool to screen for older patients with malnutrition.

Significance of Levocarnitine Treatment in Dialysis Patients

Carnitine is a naturally occurring amino acid derivative that is involved in the transport of long-chain fatty acids to the mitochondrial matrix. There, these substrates undergo β-oxidation, producing energy. The major sources of carnitine are dietary intake, although carnitine is also endogenously synthesized in the liver and kidney. However, in patients on dialysis, serum carnitine levels progressively fall due to restricted dietary intake and deprivation of endogenous synthesis in the kidney. Furthermore, serum-free carnitine is removed by hemodialysis treatment because the molecular weight of carnitine is small (161 Da) and its protein binding rates are very low. Therefore, the dialysis procedure is a major cause of carnitine deficiency in patients undergoing hemodialysis. This deficiency may contribute to several clinical disorders in such patients. Symptoms of dialysis-related carnitine deficiency include erythropoiesis-stimulating agent-resistant anemia, myopathy, muscle weakness, and intradialytic muscle cramps and hypotension. However, levocarnitine administration might replenish the free carnitine and help to increase carnitine levels in muscle. This article reviews the previous research into levocarnitine therapy in patients on maintenance dialysis for the treatment of renal anemia, cardiac dysfunction, dyslipidemia, and muscle and dialytic symptoms, and it examines the efficacy of the therapeutic approach and related issues.

The combination of malnutrition-inflammation and functional status limitations is associated with mortality in hemodialysis patients

The identification of malnutrition-inflammation-complex (MIC) and functional status (FS) is key to improving patient experience on hemodialysis (HD). We investigate the association of MIC and FS combinations with mortality in HD patients. We analyzed data from 5630 HD patients from 9 countries in DOPPS phases 4–5 (2009–2015) with a median follow-up of 23 [IQR 11, 31] months. MIC was defined as serum albumin < 3.8 g/dL and serum C-reactive protein > 3 mg/L in Japan and > 10 mg/L elsewhere. FS score was defined as the sum of scores from the Katz Index of Independence in Activities of Daily Living and the Lawton-Brody Instrumental Activities of Daily Living Scale. We investigated the association between combinations of MIC (+/−) and FS (low [< 11]/high [≥ 11]) with death. Compared to the reference group (MIC−/high FS), the adjusted hazard ratios [HR (95% CI)] for all-cause mortality were 1.82 (1.49, 2.21) for MIC−/low FS, 1.57 (1.30, 1.89) for MIC+/high FS, and 3.44 (2.80, 4.23) for MIC+/low FS groups. Similar associations were observed with CVD-related and infection-related mortality. The combination of MIC and low FS is a strong predictor of mortality in HD patients. Identification of MIC and poor FS may direct interventions to lessen adverse clinical outcomes in the HD setting.

Dental caries status is associated with arteriosclerosis in patients on hemodialysis

BACKGROUND

We previously found that worse dental caries status was associated with high pulse pressure among patients on hemodialysis, indicating that such patients might have arteriosclerosis. In this study, we used abdominal computed tomography to evaluate arteriosclerosis in patients on hemodialysis and investigated the association between arteriosclerosis and dental caries status. We also prospectively examined risk factors associated with 2-year prognosis.

METHODS

The dental caries and periodontal disease statuses of 80 patients on hemodialysis were evaluated using the decayed, missing, or filled teeth (DMFT) index, and periodontal pocket depth, respectively. The aortic calcification index was semiquantitatively measured using computed tomography images of the abdominal aorta. Clinical data were also analyzed after all patients on hemodialysis provided written, informed consent to participate in the study.

RESULTS

Regression analysis demonstrated a significant correlation between the DMFT and aortic calcification indexes. Multiple regression analysis showed that the DMFT index was significantly correlated with the aortic calcification index, following adjustment for age, sex, and dialysis period. Thirteen of the 80 patients died during the 2-year follow-up period; logistic regression analysis showed that mortality rate was significantly associated with the aortic calcification index, but not the DMFT index. However, periodontal pocket depth was not correlated with the aortic calcification index.

CONCLUSION

These findings suggest that worse dental caries status could be associated with arteriosclerosis among patients on hemodialysis, which may indirectly affect the prognosis of arteriosclerosis in these patients.

Impact of old age on the association between in-center extended-hours hemodialysis and mortality in patients on incident hemodialysis

With the global problem of aging, it has become more difficult to improve the prognosis of older dialysis patients. Extended-hours hemodialysis offers longer treatment time compared to conventional hemodialysis regimen and provides favorable metabolic status, hemodynamic stability, and increased dietary intake. Despite prior studies reporting that in-center extended-hours hemodialysis can reduce the mortality rate, the treatment impact on elderly patients remains unclear. Therefore, we examined the association between extended-hours hemodialysis compared to conventional hemodialysis and all-cause mortality. Survival analyses using Cox proportional hazard model with multivariable adjustments and propensity-score based method were performed to compare mortality risk between 198 consecutive patients who started in-center extended-hours hemodialysis (Extended-HD) and 1407 consecutive patients who initiated conventional hemodialysis. The median age was 67.1 years in the Extended-HD group and 70.7 years in the conventional hemodialysis group. Extended-HD was associated with lower all-cause mortality in overall patients and the subgroup >70 years (adjusted hazard ratios of 0.60 [95% CI, 0.39–0.91] and 0.35 [95% CI, 0.18–0.69], respectively). There was a significant interaction between age >70 years and Extended-HD. In conclusion, extended-hours hemodialysis was associated with a lower mortality rate, especially in elderly patients.

Estimation of homeostatic dysregulation and frailty using biomarker variability: a principal component analysis of hemodialysis patients

Increased intraindividual variability in several biological parameters is associated with aspects of frailty and may reflect impaired physiological regulation. As frailty involves a cumulative decline in multiple physiological systems, we aimed to estimate the overall regulatory capacity by applying a principal component analysis to such variability. The variability of 20 blood-based parameters was evaluated as the log-transformed coefficient of variation (LCV) for one year’s worth of data from 580 hemodialysis patients. All the LCVs were positively correlated with each other and shared common characteristics. In a principal component analysis of 19 LCVs, the first principal component (PC1) explained 27.7% of the total variance, and the PC1 score exhibited consistent correlations with diverse negative health indicators, including diabetes, hypoalbuminemia, hyponatremia, and relative hypocreatininemia. The relationship between the PC1 score and frailty was subsequently examined in a subset of the subjects. The PC1 score was associated with the prevalence of frailty and was an independent predictor for frailty (odds ratio per SD: 2.31, P = 0.01) using a multivariate logistic regression model, which showed good discrimination (c-statistic: 0.85). Therefore, the PC1 score represents principal information shared by biomarker variabilities and is a reasonable measure of homeostatic dysregulation and frailty.

Application of explainable ensemble artificial intelligence model to categorization of hemodialysis-patient and treatment using nationwide-real-world data in Japan

BACKGROUND

Although dialysis patients are at a high risk of death, it is difficult for medical practitioners to simultaneously evaluate many inter-related risk factors. In this study, we evaluated the characteristics of hemodialysis patients using machine learning model, and its usefulness for screening hemodialysis patients at a high risk of one-year death using the nation-wide database of the Japanese Society for Dialysis Therapy.

MATERIALS AND METHODS

The patients were separated into two datasets (n = 39,930, 39,930, respectively). We categorized hemodialysis patients in Japan into new clusters generated by the K-means clustering method using the development dataset. The association between a cluster and the risk of death was evaluated using multivariate Cox proportional hazards models. Then, we developed an ensemble model composed of the clusters and support vector machine models in the model development phase, and compared the accuracy of the prediction of mortality between the machine learning models in the model validation phase.

RESULTS

Average age of the subjects was 65.7±12.2 years; 32.7% had diabetes mellitus. The five clusters clearly distinguished the groups on the basis of their characteristics: Cluster 1, young male, and chronic glomerulonephritis; Cluster 2, female, and chronic glomerulonephritis; Cluster 3, diabetes mellitus; Cluster 4, elderly and nephrosclerosis; Cluster 5, elderly and protein energy wasting. These clusters were associated with the risk of death; Cluster 5 compared with Cluster 1, hazard ratio 8.86 (95% CI 7.68, 10.21). The accuracy of the ensemble model for the prediction of 1-year death was 0.948 and higher than those of logistic regression model (0.938), support vector machine model (0.937), and deep learning model (0.936).

CONCLUSIONS

The clusters clearly categorized patient on their characteristics, and reflected their prognosis. Our real-world-data-based machine learning system is applicable to identifying high-risk hemodialysis patients in clinical settings, and has a strong potential to guide treatments and improve their prognosis.

Effects of online hemodiafiltration on anemia and nutritional status in chronic hemodialysis patients

Background

Online hemodiafiltration (OL-HDF) offers considerable advantages in clearance of molecules of various sizes. However, evidence of clinical effects of OL-HDF is scarce in Korea. In this study, we investigated changes in laboratory values over more than 12 months after switching to OL-HDF.

Methods

Adult patients with end-stage renal disease undergoing hemodialysis (HD) were prospectively enrolled in a K-cohort (CRIS no. KCT0003281) from 6 tertiary hospitals in South Korea. We recruited 435 patients, 339 of whom were on HD at enrollment. One hundred eighty-two patients were followed for more than 24 months. Among them, 44 were switched to OL-HDF for more than 12 months without conversion to HD. We used a paired t test to compare baseline and 24-month follow-up results.

Results

The mean age of the subjects was 61.2 ± 12.2 years, and 62.6% were male. The baseline hemoglobin level was not significantly different between HD and OL-HDF group (10.61 ± 1.15 vs. 10.46 ± 1.03 g/dL, P = 0.437). However, the baseline serum protein and albumin levels were significantly lower in the OL-HDF group (6.82 ± 0.49 vs. 6.59 ± 0.48 g/dL, P = 0.006; 3.93 ± 0.28 vs. 3.73 ± 0.29 g/dL, P < 0.001). In patients switched to OL-HDF, levels of hemoglobin and serum albumin significantly increased (10.46 ± 1.03 vs. 11.08 ± 0.82 g/dL, P = 0.001; 3.73 ± 0.29 vs. 3.87 ± 0.30 g/dL, P = 0.001). The normalized protein catabolic rate decreased after 24 months, but the change was not significant (1.07 ± 0.25 vs. 1.03 ± 0.21 g/kg/day, P = 0.433). Although the dose of erythropoiesis-stimulating agent was lower in patients who converted to HDF, it was not significantly different (-115.7 ± 189.7 vs. -170.5 ± 257.1 P = 0.206).

Conclusion

OL-HDF treatment over more than 12 months was associated with no harmful effects on anemia and nutritional status.

Prevalence of Zinc Deficiency in Japanese Patients on Peritoneal Dialysis: Comparative Study in Patients on Hemodialysis

BACKGROUND

It is known that patients on hemodialysis (HD) are prone to developing zinc deficiency due to removal of zinc by HD, inadequate dietary intake, and reduced gastrointestinal zinc absorption. However, the prevalence of zinc deficiency in patients on peritoneal dialysis (PD) has not been well established.

METHODS

Serum zinc levels were compared between 47 patients on PD and 47 patients on HD matched for age, sex, and duration of dialysis. A serum zinc level < 60 μg/dL was defined as clinical zinc deficiency and a level of 60-80 μg/dL as subclinical zinc deficiency. The prevalence of zinc deficiency and associated clinical factors were determined in both groups.

RESULTS

Clinical zinc deficiency was found in 59.6% of the PD group and 70.2% of the HD group (p = 0.391). Subclinical zinc deficiency was found in 40.4% of the PD group and 29.8% of the HD group. Age, body mass index, and serum albumin level were identified as independent predictors of zinc deficiency in the PD group by multivariate analysis.

CONCLUSIONS

A higher prevalence of clinical and subclinical zinc deficiency was found in patients on PD. The rates were comparable between patients on PD and those on HD after adjustment for confounding factors.

Possible link between dental diseases and arteriosclerosis in patients on hemodialysis

BACKGROUND

Patients on hemodialysis must undergo this procedure at a hospital three times weekly and might be unable to visit a dentist. In addition, dentists might hesitate to provide oral care because such patients tend to bleed because they are medicated with anticoagulants, are susceptible to bacterial infections, and might have unusual drug reactions. We postulated that patients on hemodialysis have worse oral status than healthy people, which in turn might predispose such patients to systemic complications.

METHODS

We compared the status of dental caries and periodontal diseases among 80 patients on hemodialysis and 76 healthy individuals (controls) using the decayed, missing, or filled teeth (DMFT) index, total number of C4 teeth (destruction of the entire tooth crown), and periodontal pocket depth. Clinical data were analyzed after all patients on hemodialysis and controls provided written, informed consent to participate in the study.

RESULTS

Total number of C4 teeth (p = 0.021), missing teeth (MT) index (p = 0.0302), and DMFT index score ≥ 24 (p = 0.017) were significantly higher in patients on hemodialysis than controls. Pulse pressure (p = 0.0042) and the prevalence of a history of heart disease such as angina pectoris and acute myocardial infarction (p = 0.029) were higher in patients on hemodialysis with higher (≥ 24) than lower (< 24) DMFT index scores. Periodontal pocket depth was not significantly different between these two groups.

CONCLUSION

Worse status of dental caries is possibly associated with arteriosclerosis among patients on hemodialysis.

Periodontal Disease in Patients Receiving Dialysis

Chronic kidney disease (CKD) is characterized by kidney damage with proteinuria, hematuria, and progressive loss of kidney function. The final stage of CKD is known as end-stage renal disease, which usually indicates that approximately 90% of normal renal function is lost, and necessitates renal replacement therapy for survival. The most widespread renal replacement therapy is dialysis, which includes peritoneal dialysis (PD) and hemodialysis (HD). However, despite the development of novel medical instruments and agents, both dialysis procedures have complications and disadvantages, such as cardiovascular disease due to excessive blood fluid and infections caused by impaired immunity. Periodontal disease is chronic inflammation induced by various pathogens and its frequency and severity in patients undergoing dialysis are higher compared to those in healthy individuals. Therefore, several investigators have paid special attention to the impact of periodontal disease on inflammation-, nutrient-, and bone metabolism-related markers; the immune system; and complications in patients undergoing dialysis. Furthermore, the influence of diabetes on the prevalence and severity of manifestations of periodontal disease, and the properties of saliva in HD patients with periodontitis have been reported. Conversely, there are few reviews discussing periodontal disease in patients with dialysis. In this review, we discuss the available studies and review the pathological roles and clinical significance of periodontal disease in patients receiving PD or HD. In addition, this review underlines the importance of oral health and adequate periodontal treatment to maintain quality of life and prolong survival in these patients.

Nutritional Laboratory Markers in Malnutrition

Serum visceral proteins such as albumin and prealbumin have traditionally been used as markers of the nutritional status of patients. Prealbumin is nowadays often preferred over albumin due to its shorter half live, reflecting more rapid changes of the nutritional state. However, recent focus has been on an appropriate nutrition-focused physical examination and on the patient's history for diagnosing malnutrition, and the role of inflammation as a risk factor for malnutrition has been more and more recognized. Inflammatory signals are potent inhibitors of visceral protein synthesis, and the use of these proteins as biomarkers of the nutritional status has been debated since they are strongly influenced by inflammation and less so by protein energy stores. The current consensus is that laboratory markers could be used as a complement to a thorough physical examination. Other markers of the nutritional status such as urinary creatinine or 3-methylhistidine as indicators of muscle protein breakdown have not found widespread use. Serum IGF-1 is less influenced by inflammation and falls during malnutrition. However, its concentration changes are not sufficiently specific to be useful clinically as a marker of malnutrition, and serum IGF-1 has less been used in clinical trials. Nevertheless, biomarkers of malnutrition such as prealbumin may be of interest as easily measurable predictors of the prognosis for surgical outcomes and of mortality in severe illnesses.