Chronic kidney disease and end-stage renal disease in the elderly population: current prevalence, future projections, and clinical significance

Cerebral white matter burden is linked to cognitive function in patients undergoing hemodialysis

INTRODUCTION

Chronic kidney disease is related to neurodegeneration and structural changes in the brain which might lead to cognitive decline. The Fazekas scale used for assessing white matter hyperintensities (WMHs) was associated with poor cognitive performance. Therefore, this study investigated the associations between the mini-mental status examination (MMSE), Montreal cognitive assessment (MoCA), cognitive abilities screening instrument (CASI), and Fazekas scale in patients under hemodialysis (HD).

METHODS

The periventricular (PV) WMHs and deep WMHs (DWMHs) in brain magnetic resonance images of 59 patients under dialysis were graded using the Fazekas scale. Three cognition function tests were also performed, then multivariable ordinal regression and logistic regression were used to identify the associations between cognitive performance and the Fazekas scale.

RESULTS

There were inverse associations between the three cognitive function tests across the Fazekas scale of PVWMHs (p = .037, .006, and .008 for MMSE, MoCA, and CASI, respectively), but the associations were attenuated in the DWMHs group. In CASI, significant differences were identified in short-term memory, mental manipulation, abstract thinking, language, spatial construction, and name fluency in the PVWMHs group. However, DWMHs were only significantly correlated with abstract thinking and short-term memory.

CONCLUSION

An inverse correlation existed between the Fazekas scale, predominantly in PVWMHs, and cognition in patients undergoing HD. The PVWMHs were associated with cognitive performance assessed by MMSE, MoCA, and CASI, as well as with subdomains of CASI such as memory, language and name fluency in patients undergoing HD.

Epithelial cell states associated with kidney and allograft injury

The kidney epithelium, with its intricate arrangement of highly specialized cell types, constitutes the functional core of the organ. Loss of kidney epithelium is linked to the loss of functional nephrons and a subsequent decline in kidney function. In kidney transplantation, epithelial injury signatures observed during post-transplantation surveillance are strong predictors of adverse kidney allograft outcomes. However, epithelial injury is currently neither monitored clinically nor addressed therapeutically after kidney transplantation. Several factors can contribute to allograft epithelial injury, including allograft rejection, drug toxicity, recurrent infections and postrenal obstruction. The injury mechanisms that underlie allograft injury overlap partially with those associated with acute kidney injury (AKI) and chronic kidney disease (CKD) in the native kidney. Studies using advanced transcriptomic analyses of single cells from kidney or urine have identified a role for kidney injury-induced epithelial cell states in exacerbating and sustaining damage in AKI and CKD. These epithelial cell states and their associated expression signatures are also observed in transplanted kidney allografts, suggesting that the identification and characterization of transcriptomic epithelial cell states in kidney allografts may have potential clinical implications for diagnosis and therapy.

Is blood pTau a reliable indicator of the CSF status? A narrative review

BACKGROUND

The identification of biomarkers for the early diagnosis of Alzheimer's disease (AD) is a crucial goal of the current research. Blood biomarkers are less invasive, easier to obtain and achievable by a cheaper means than those on cerebrospinal fluid (CSF) and significantly more economic than functional neuroimaging investigations; thus, a great interest is focused on blood isoforms of the phosphorylated Tau protein (pTau), indicators of ongoing tau pathology (i.e. neurofibrillary tangles, NFTs, an AD neuropathological hallmark) in the central nervous system (CNS). However, current data often highlight discordant results about the ability of blood pTau to predict CSF status.

OBJECTIVE

We aim to synthesise the studies that compared pTau levels on CSF and blood to assess their correlation in AD continuum.

METHODS

We performed a narrative literature review using, first, MEDLINE (via PubMed) by means of MeSH terms, and then, we expanded the reults by means of Scopus and Web of Sciences to be as inclusive as possible. Finally, we added work following an expert opinion. Only papers presenting original data on pTau values on both blood and CSF were included.

RESULTS

The 33 included studies show an extreme heterogeneity in terms of pTau isoform (pTau181, 217 and 231), laboratory methods, diagnostic criteria and choice of comparison groups. Most studies evaluated plasma pTau181, while data on other isoforms and serum are scarcer.

DISCUSSION

Most papers identify a correlation between CSF and blood measurements. Furthermore, even when not specified, it is often possible to show an increase in blood pTau values as AD-related damage progresses in the AD continuum and higher values in AD than in other neurodegenerative diseases. Notably, plasma pTau231 seems the first biomarker to look for in the earliest and pre-clinical stages, quickly followed by pTau217 and, finally, by pTau181.

CONCLUSIONS

Our results encourage the use of blood pTau for the early identification of patients with AD continuum.

Systematic review and meta-analysis of preoperative predictors for early mortality following hip fracture surgery

Hip fractures are a global health problem with a high postoperative mortality rate. Preoperative predictors for early mortality could be used to optimise and personalise healthcare strategies. This study aimed to identify predictors for early mortality following hip fracture surgery. Cohort studies examining independent preoperative predictors for mortality following hip fracture surgery were identified through a systematic search on Scopus and PubMed. Predictors for 30-day mortality were the primary outcome, and predictors for mortality within 1 year were secondary outcomes. Primary outcomes were analysed with random-effects meta-analyses. Confidence in the cumulative evidence was assessed using the GRADE criteria. Secondary outcomes were synthesised narratively. Thirty-three cohort studies involving 462,699 patients were meta-analysed. Five high-quality evidence predictors for 30-day mortality were identified: age per year (OR: 1.06, 95% CI: 1.04-1.07), ASA score ≥ 3 (OR: 2.69, 95% CI: 2.12-3.42), male gender (OR: 2.00, 95% CI: 1.85-2.18), institutional residence (OR: 1.81, 95% CI: 1.31-2.49), and metastatic cancer (OR: 2.83, 95% CI: 2.58-3.10). Additionally, six moderate-quality evidence predictors were identified: chronic renal failure, dementia, diabetes, low haemoglobin, heart failures, and a history of any malignancy. Weak evidence was found for non-metastatic cancer. This review found relevant preoperative predictors which could be used to identify patients who are at high risk of 30-day mortality following hip fracture surgery. For some predictors, the prognostic value could be increased by further subcategorising the conditions by severity.

Unusual Presentation of Staphylococcal Scalded Skin Syndrome in an Elderly Patient With Acute Kidney Injury: A Case Report

Staphylococcal Scalded Skin Syndrome (SSSS) is characterized by denudation of the skin caused by Staphylococcus species. SSSS is common in infants, children, and rarely immunosuppressed adults or those with severe renal disease. We report a case of a 70-year-old female patient with an acute kidney injury who developed peeling of the skin over the axilla and back, which gradually spread to involve the upper and lower limbs, chest, and abdomen. A skin biopsy was performed, and a histopathological examination revealed a sub-corneal split consistent with SSSS. The patient was diagnosed with adult SSSS and was started on treatment with intravenous antibiotics, following which the skin lesions resolved.

Comparison of young and old patients on peritoneal dialysis: A retrospective observational study

BACKGROUND

With a global increase in life expectancy around the world, the burden of chronic kidney disease in the elderly is increasing. The number of elderly patients undergoing peritoneal dialysis (PD) is also increasing. There is still a perception that PD may be associated with an increased risk of complications in these elderly patients.

METHODS

A total of 311 patients, of which 103 PD patients aged 65 and over and 208 PD patients under 65 years of age, were followed in a single center and evaluated, retrospectively. Demographic data of these patients, albumin values at first PD and during PD time, residual urine amount, number of peritonitis, time to the first peritonitis attack, PD endpoints, and mortality were compared.

RESULTS

Peritonitis and technique failure rates were lower in patients aged 65 and over who applied PD (0.61-0.75, 6.8%-23.1%, respectively). There was no difference in peritonitis-free survival (p = 0.931). Need for help HR 2.569 [95%CI 1.564-4.219] (p < 0.05), time to first peritonitis attack HR 0.983 [95%CI 0.974-0.992] (p < 0.05), mean albumin value HR 0.191 [95%CI 0.088-0.413] (p < 0.05), urine output level HR 1.154 [95%CI 1.010-1.318] (p < 0.05) were factors affecting mortality.

CONCLUSION

Peritonitis and technical survival evaluations of elderly PD patients, other than mortality, were lower than younger PD patients. However, the need for help is one of the biggest obstacles to this method for the elderly. We believe that incentives in this regard will increase the number of elderly PD patients.

Effect of Paricalcitol Combined with Cinacalcet on Calcium and Phosphorus Metabolism in Patients Receiving Maintenance Hemodialysis

This study was designed to compare the beneficial effects of paricalcitol combined with or without cinacalcet on calcium and phosphorus metabolism in patients undergoing maintenance hemodialysis (MHD). A total of 140 patients who received MHD in our hospital from March 2021 to March 2022 were randomly divided into a control group (intravenous paricalcitol, n = 70) and a test group (intravenous paricalcitol combined with oral cinacalcet, n = 70). Clinical baseline data and relevant laboratory parameters before treatment were compared. Additionally, calcium, phosphorus, intact parathyroid hormone in serum were measured and compared between the 2 groups before treatment and 1, 2, 3, 4, 5, 6, 9, 10, and 12 months after treatment. As a result, comparison before treatment demonstrated no significant difference in baseline data such as age, sex, and most laboratory parameters between the 2 groups (P > .05), but there was a significant difference in mean corpuscular volume (P < .001). The serum phosphorus level decreased and calcium level increased significantly in the 2 groups after treatment, while the intact parathyroid hormone level showed no significant change within 12 months of treatment (P > .05). In addition, the combined treatment for 6-12 months caused a much lower phosphorus level (P < .05) and higher calcium level (P < .05) than the treatment with paricalcitol alone, and the difference increased with the extension of treatment time. Collectively, paricalcitol combined with cinacalcet, which is more effective than paricalcitol alone, has a positive effect on calcium and phosphorus metabolism in patients receiving MHD.

Immunological features of ESRD patients undergoing hemodialysis of various ages

AIMS

To investigate the immunological characteristics of hemodialysis (HD) patients with end-stage renal disease (ESRD) of various ages, and the impact of age-related immune alterations on these patients, with a focus on peripheral T cells.

METHODS

From September 2016 to September 2019, HD patients were enrolled and followed prospectively for 3 years. Patients were divided into three groups based on their ages: < 45, 45 to 64, and ≥ 65. The distribution of T cell subsets in different age groups was investigated and compared. The effects of altered T cell subsets on overall survival were also investigated.

RESULTS

A total of 371 HD patients were enrolled. The reduced number of naive CD8+ T cells (P < 0.001) and increased number of EMRA CD8+ T cells (P = 0.024) were independently associated with the advanced age among all T cell subsets studied. Patient survival may be affected by numerical changes in naive CD8+ T cells. However, when HD patients were < 45 or ≥ 65 years, the reduction had no significant impact on survival. Only in HD patients aged 45 to 64 years, the number of naïve CD8+ T cells found to be insufficient but not deficient, identified as an independent predictor of poor survival.

CONCLUSIONS

The most significant age-related immune change in HD patients was a decrease in peripheral naive CD8+ T cells, which was an independent predictor of 3-year overall survival in HD patients aged 45 ~ 64 years.

Nuclear Receptor PPARα as a Therapeutic Target in Diseases Associated with Lipid Metabolism Disorders

Lipid metabolic diseases have substantial morbidity and mortality rates, posing a significant threat to human health. PPARα, a member of the peroxisome proliferator-activated receptors (PPARs), plays a crucial role in lipid metabolism and immune regulation. Recent studies have increasingly recognized the pivotal involvement of PPARα in diverse pathological conditions. This comprehensive review aims to elucidate the multifaceted role of PPARα in metabolic diseases including liver diseases, diabetes-related diseases, age-related diseases, and cancers, shedding light on the underlying molecular mechanisms and some regulatory effects of natural/synthetic ligands of PPARα. By summarizing the latest research findings on PPARα, we aim to provide a foundation for the possible therapeutic exploitation of PPARα in lipid metabolic diseases.

Effectiveness of thyme honey in the management of xerostomia in geriatric patients with end-stage renal disease: a randomized controlled clinical trial with a biochemical assessment

BACKGROUND

Taking into consideration the value of the oral health condition in geriatric people with end-stage renal disease (ESRD) associated with xerostomia and believing that salivary stimulants or substitutes could potentially be used to manage this condition. This study aimed to evaluate the clinical effectiveness of thyme honey as oral rinse in geriatric patients with ESRD using the subjective dry mouth score as a primary objective and to assess the effect of thyme honey on the salivary nitric oxide level, salivary flow rate, and salivary ph in addition to objective dry mouth score as a secondary objective.

METHODS

This was a single blinded randomized controlled trial with two equal arms, the interventional arm (thyme honey oral rinse) and the control arm (saline). Twenty-eight geriatric patients with ESRD undergoing hemodialysis complained of xerostomia were recruited from the renal dialysis center. Patients in both arms followed the same administration protocol either with thyme honey oral rinse or saline. The following clinical parameters (the subjective and objective dry mouth scores, salivary flow rate, salivary ph, and salivary nitric oxide (NO) levels) were evaluated for both groups at different intervals (baseline, 1 week, and 1 month).

RESULTS

In the current study, it was found that both the subjective and objective dry mouth scores were significantly lower after one month of using thyme honey oral rinse (1.86 ± 0.66B) and (2.21 ± 0.43B) respectively, than the control group (3.07 ± 0.73B) and (3.07 ± 0.83B), respectively with a (p < 0.001). Also, the salivary flow rate was significantly higher after one month of using thyme honey oral rinse (1.56 ± 0.51A), than the control group (0.78 ± 0.27A) with a (p < 0.001). For the NO levels, there was a significant increase in measured value after 1 month in the intervention group (p < 0.001), while for the control group the change was not statistically significant (p = 0.166).

CONCLUSIONS

The results of the current study have revealed the efficacy of Thyme honey oral rinse in the management of xerostomia in geriatric patients with ESRD. Trial registration The ClinicalTrials.gov Identifier for this study is NCT05247008.

The impact of in-centre haemodialysis treatment on the everyday life of older adults with end-stage kidney disease: a qualitative study

Background

Older adults with end-stage kidney disease experience a diminished ability to perform the activities of their daily life. For those living at home, the initiation of in-centre haemodialysis treatment (ICHD) carries a risk of cascading functional decline leading to early nursing home placement and mortality. Research on how older adults adapt to their newly impacted daily life is scarce.

Methods

Individual semi-structured interviews were conducted using a purposeful maximum variation sample of older adult (≥65 years) ICHD patients living at home. Interviews were conducted between October and December 2018. Interview coding followed an inductive and broad-based approach. Thematic analysis was used to group meaning units into common themes and subthemes.

Results

Twenty patients (12 females) were interviewed. Analysis resulted in two main themes and seven subthemes. The first main theme showed the impact of ICHD on everyday roles and functioning through four subthemes: a stepwise decline in daily activities, managing time, role changes and an incomplete retirement. The second main theme showed potential areas of remediation through three subthemes: the social environment, developing new daily activity patterns and meaningful activities and goals.

Conclusions

The older adults experienced a process of adaptation that generally progressed from a phase of initial disruption towards a period of mere survival. Being able to accept a life on dialysis was intricately connected with the ability to perform activities that were personally meaningful. Early and continued support of meaningful activities may prove valuable in breaking or delaying the cycle of functional decline.

Medication-Related Problems and Their Intervention in the Geriatric Population: A Review of the Literature

In order to implement the principles of providing clinically and economically effective care, the current state of healthcare must be evaluated, and challenges must be addressed. As part of a physician's role in such a context, one tool consists of identifying medication-related problems (MRPs) and accordingly implementing best practices and innovative strategies to improve patient healthcare outcomes. The geriatric population is expected to have passed through the natural ageing process and experienced several physiological and biological changes that impact their bodies and lives. In the presence of geriatric syndromes and the increased number of medications consumed, the risk of MRPs such as polypharmacy, potentially inappropriate medication (PIM), adverse events, drug-drug interactions, and risk of non-adherence increases. Different interventions that focus on practical and perceptual barriers have been studied, and different tools to define clinically important prescribing problems relating to PIM have been established. The Beers Criteria and STOPP (Screening Tool of Older Persons' Prescriptions)/START (Screening Tool to Alert to Right Treatment) criteria are the most widely used sets of explicit PIM criteria; however, they are still limited in Saudi Arabia. These tools should be considered in clinical settings to improve healthcare outcomes in the geriatric population, and the clinical relevance of enhancing medication should also be explored from the point of view of both the patient and healthcare practitioners.

Associations of FGF23 with 10-Year Change in eGFR and UACR and with Incident CKD in the CARDIA Cohort

Key Points

FGF23 has a nonlinear positive association with incident CKD among healthy, middle-aged adults. The relationship between FGF23 and incident CKD was only significant among participants with cFGF23 levels in the highest quartile. FGF23 is not associated with 10-year change in eGFR or 10-year change in UACR among healthy, middle-aged adults.

Background

The relationship of fibroblast growth factor 23 (FGF23) with incident CKD has been examined in older but not younger populations.

Methods

Linear regression models were used to examine the associations of c-terminal FGF23 (cFGF23) and intact FGF23 (iFGF23) with 10-year change (1995–96 to 2005–06) in eGFR and urine albumin-to-creatinine ratio (UACR) in the Coronary Artery Risk Development in Young Adults cohort. Cox proportional hazard models were used to assess the association of cFGF23 with incident CKD, defined as eGFR <60 ml/min per 1.73 m2 or UACR ≥30 mg/g. Multivariable models were adjusted for age, sex, race, education, field center, physical activity, body mass index, diabetes, smoking, and systolic BP.

Results

Among 2511 participants, the mean age was 45±3.6 years; mean eGFR was 96.5±14.0 ml/min per 1.73 m2; and median UACR was 4.3 (interquartile range, 3.0–6.7) mg/g. Most (62.6%) participants were nonsmokers; the prevalence of diabetes was low (6.6%); and median values for 10-year changes in eGFR and UACR were modest (−5.50 ml/min per 1.73 m2 and 0.70 mg/g, respectively). No consistent associations between cFGF23 and 10-year change in eGFR and UACR were observed. During a median follow-up of 9.98 years, incident CKD developed in 258 participants. There was a nonlinear association of cFGF23 with incident CKD, and relative to the lowest quartile of cFGF23, a significant relationship was detected only among participants in the highest quartile (hazard ratio, 1.58; 95% confidence interval, 1.09 to 2.27). Similar findings were observed for iFGF23.

Conclusion

Among middle-aged adults in the Coronary Artery Risk Development in Young Adults cohort, median eGFR and UACR changes were modest and cFGF23 and iFGF23 were not consistently associated with 10-year change in eGFR or UACR. A nonlinear relationship was observed between cFGF23 and incident CKD, with individuals with highest cFGF23 levels being at risk of developing CKD.

Underdiagnosed CKD in Geriatric Trauma Patients and Potent Prevention of Renal Impairment from Polypharmacy Risks through Individual Pharmacotherapy Management (IPM-III)

The aging global patient population with multimorbidity and concomitant polypharmacy is at increased risk for acute and chronic kidney disease, particularly with severe additional disease states or invasive surgical procedures. Because from the expertise of more than 58,600 self-reviewed medications, adverse drug reactions, drug interactions, inadequate dosing, and contraindications all proved to cause or exacerbate the worsening of renal function, we analyzed the association of an electronic patient record- and Summaries of Product Characteristics (SmPCs)-based comprehensive individual pharmacotherapy management (IPM) in the setting of 14 daily interdisciplinary patient visits with the outcome: further renal impairment with reduction of eGFR ≥ 20 mL/min (redGFR) in hospitalized trauma patients ≥ 70 years of age. The retrospective clinical study of 404 trauma patients comparing the historical control group (CG) before IPM with the IPM intervention group (IG) revealed a group-match in terms of potential confounders such as age, sex, BMI, arterial hypertension, diabetes mellitus, and injury patterns. Preexisting chronic kidney disease (CKD) > stage 2 diagnosed as eGFR < 60 mL/min/1.73 m² on hospital admission was 42% in the CG versus 50% in the IG, although in each group only less than 50% of this was coded as an ICD diagnosis in the patients' discharge letters (19% in CG and 21% in IG). IPM revealed an absolute risk reduction in redGFR of 5.5% (11 of 199 CG patients) to 0% in the IPM visit IG, a relative risk reduction of 100%, NNT 18, indicating high efficacy of IPM and benefit in improving outcomes. There even remained an additive superimposed significant association that included patients in the IPM group before/beyond the 14 daily IPM interventions, with a relative redGFR risk reduction of 0.55 (55%) to 2.5% (5 of 204 patients), OR 0.48 [95% CI 0.438-0.538] (p < 0.001). Bacteriuria, loop diuretics, allopurinol, eGFR ≥ 60 mL/min/1.73 m², eGFR < 60 mL/min/1.73 m², and CKD 3b were significantly associated with redGFR; of the latter, 10.5% developed redGFR. Further multivariable regression analysis adjusting for these and established risk factors revealed an additive, superimposed IPM effect on redGFR with an OR 0.238 [95% CI 0.06-0.91], relative risk reduction of 76.2%, regression coefficient -1.437 including patients not yet visited in the IPM period. As consequences of the IPM procedure, the IG differed from the CG by a significant reduction of NSAIDs (p < 0.001), HCT (p = 0.028) and Würzburger pain drip (p < 0.001), and significantly increased prescription rate of antibiotics (p = 0.004). In conclusion, (1) more than 50% of CKD in geriatric patients was not pre-recognized and underdiagnosed, and (2) the electronic patient records-based IPM interdisciplinary networking strategy was associated with effective prevention of further periinterventional renal impairment and requires obligatory implementation in all elderly patients to urgently improve patient and drug safety.

Risk of developing chronic kidney disease in young-onset Type 2 diabetes in Korea

We investigated the risk of developing chronic kidney disease (CKD) in patients with young-onset Type 2 diabetes (YOD, diagnosed age < 40 years). We enrolled 84,384 patients aged 20-64 who started anti-diabetic medication between 2010 and 2011 from the Korea National Health Insurance Sharing Service; patients with Type 1 diabetes or a history of CKD were excluded. Multivariate logistic regression analyses were performed to adjust for YOD-distinct variables and compare the incidence of CKD between YOD and late-onset diabetes (LOD, diagnosed age ≥ 40 years). During the median observation period of 5.16 years (interquartile range: 4.58-5.77 years), 1480 out of 77,039 LOD patients and 34 out of 7345 YOD patients developed CKD. Patients with YOD had distinct baseline characteristics compared with the patients with LOD. The odds ratio of developing CKD in patients with YOD over LOD was 1.70 (95% CI 1.15-2.51) after adjusting clinically distinct variables. The increased CKD odds in YOD compared with LOD was greater in the non-smoking group (OR 2.03, 95% CI 1.26-3.26) than in the smoking group (OR 1.49, 95% CI 0.74-2.98, p = 0.0393 for interaction). Among YOD patients, hypertension (34.76% vs. 64.71%, p = 0.0003), dyslipidemia (46.87% vs. 73.53%, p = 0.0019), and sulfonylurea use (35.54% vs. 52.94%, p = 0.0345) were associated with CKD development. YOD patients have a greater risk of developing CKD than LOD patients after adjusting clinically distinct variables.

Nutritional Interventions: Dietary Protein Needs and Influences on Skeletal Muscle of Older Adults

BACKGROUND

This narrative review describes foundational and emerging evidence of how dietary protein intakes may influence muscle-related attributes of older adults.

METHODS

PubMed was used to identify pertinent research.

RESULTS

Among medically stable older adults, protein intakes below the recommended dietary allowance (RDA) (0.8 g/kg body weight [BW]/d) exacerbate age-related reductions in muscle size, quality, and function. Dietary patterns with total protein intakes at or moderately above the RDA, including one or preferably more meals containing sufficient dietary protein to maximize protein anabolism, promote muscle size and function. Some observational studies suggest protein intakes from 1.0 to 1.6 g/kg BW/d may promote greater muscle strength and function more so than muscle size. Experimental findings from randomized controlled feeding trials indicate protein intakes greater than the RDA (averaging ~1.3 g/kg BW/d) do not influence indices of lean body mass or muscle and physical functions with non-stressed conditions, but positively influence changes in lean body mass with purposeful catabolic (energy restriction) or anabolic (resistance exercise training) stressors. Among older adults with diagnosed medical conditions or acute illness, specialized protein or amino acid supplements that stimulate muscle protein synthesis and improve protein nutritional status may attenuate the loss of muscle mass and function and improve survival of malnourished patients. Observational studies favor animal versus plant protein sources for sarcopenia-related parameters.

CONCLUSIONS

Quantity, quality, and patterning of dietary protein consumed by older adults with varied metabolic states, and hormonal and health status influence the nutritional needs and therapeutic use of protein to support muscle size and function.

Chronic kidney disease-related sarcopenia as a prognostic indicator in elderly haemodialysis patients

BACKGROUND

The mortality of dialysis patients greatly exceeds that of the general population and identifying predictive factors for mortality may provide opportunities for earlier intervention. This study assessed the influence of sarcopenia on mortality in patients on haemodialysis.

METHODS

This prospective, observational study enrolled 77 haemodialysis patients aged 60 years and over, of whom 33 (43%) were female, from two community dialysis centres. Baseline demographic and laboratory data were collected, and sarcopenia was diagnosed using grip strength, muscle mass by bioimpedance analysis (BIA) and muscle function by timed up-and-go according to European Working Group on Sarcopenia in Older People criteria. Nutritional status was assessed using a subjective nutritional assessment score, comprising functional changes in weight, appetite, gastrointestinal symptoms and energy.. A comorbidity score (maximum 7 points) was derived from the presence or absence of hypertension, ischaemic heart disease, vascular disease (cerebrovascular disease, peripheral vascular disease, and abdominal aortic aneurysm), diabetes mellitus, respiratory disease, a history of malignancy and psychiatric disease. Outcomes over six years were linked to the Australian and New Zealand Dialysis and Transplant Registry.

RESULTS

The median participant age was 71 years (range 60-87). Probable and confirmed sarcopenia was present in 55.9% and severe sarcopenia with reduced functional testing in 11.7%. Over 6 years, overall mortality was 50 of the 77 patients (65%), principally from cardiovascular events, dialysis withdrawal and infection. There were no significant survival differences between patients with no, probable, confirmed, or severe sarcopenia, or between tertiles of the nutritional assessment score. After adjustment for age, dialysis vintage, mean arterial pressure (MAP) and the total comorbidity score, no sarcopenia category predicted mortality. However, the total comorbidity score [Hazard Ratio (HR) 1.27, Confidence Intervals (CI) 1.02, 1.58, p = 0.03] and MAP (HR 0.96, CI 0.94, 0.99, P = < 0.01) predicted mortality.

CONCLUSION

Sarcopenia is highly prevalent in elderly haemodialysis patients but is not an independent predictor of mortality. Haemodialysis patients have multiple competing risks for mortality which, in this study, was predicted by a lower MAP and a higher total comorbidity score.

TRIAL REGISTRATION

Recruitment commenced December 2011. The study was registered 10.01.2012 with the Australian New Zealand Clinical Trials Registry (ACTRN12612000048886).

Safety of a 24-h-or-less break-in period in elderly patients undergoing urgent-start peritoneal dialysis: A multicenter retrospective cohort study

BACKGROUND

Several elderly patients with end-stage renal disease (ESRD) had to undergo urgent-start peritoneal dialysis (USPD). This study aimed to determine whether break-in period (BI) within 24 h was feasible in elderly patients undergoing USPD.

METHODS

Patients with ESRD who underwent PD at five hospitals were screened. Patients were divided into the BI ≤24 h and >24 h groups. Complications were compared between the two groups. Multivariate logistic regression model was used to determine whether BI ≤24 h was associated with complications.

RESULTS

A total of 175 elderly patients were included: BI ≤24 h group, 78; and BI >24 h group, 97. There was no significant difference in the rate of complications between the two groups (all p > 0.05). Furthermore, BI ≤24 h was not an independent risk factor for complications (all p > 0.05).

CONCLUSIONS

Starting PD within 24 h after PD catheter insertion was feasible in elderly ESRD patients.

Prevalence and risk factors of chronic kidney disease among patients with type 2 diabetes mellitus at a tertiary care hospital in Nepal: a cross-sectional study

OBJECTIVE

To estimate the prevalence of chronic kidney disease (CKD) among patients with type 2 diabetes mellitus (T2DM) and determine the sociodemographic and clinical risk factors associated with CKD.

DESIGN AND SETTINGS

Cross-sectional study among diabetic outpatients of a tertiary hospital in Nepal.

PARTICIPANTS

201 patients with T2DM above 18 years of age.

INTERVENTION

Participants completed a questionnaire regarding their socioeconomic information and underwent pertinent physical and haematological examinations.

PRIMARY AND SECONDARY OUTCOMES MEASURE

The prevalence and risk factors of CKD among patients with T2DM.

RESULTS

The prevalence of CKD in T2DM was 86.6%. In univariable analysis, the variables like age (p=0.026), hypertension status (p=0.002), duration of diabetes (p=0.009) and haemoglobin levels (p=0.027) were significantly associated with CKD among the participants with T2DM. Kruskal-Wallis H test showed that age was significantly different between various CKD stages. Multivariate analysis demonstrated a significant relationship between CKD with age (Adjusted odds ratio (AOR) 3, 95% CI 1.1 to 8.8) and literacy status (AOR 5.8, 95% CI 1.4 to 24.6) CONCLUSION: Advancing age, concomitant hypertension, increasing duration of T2DM and presence of anaemia were found to be important risk factors of CKD. Age is the most important predictor of CKD showing increasing prevalence in the elderly population. Periodic screening tests are essential at an early age to identify kidney diseases at incipient stages, thereby preventing progression to end-stage renal disease.

Focusing on Phosphorus Loads: From Healthy People to Chronic Kidney Disease

Phosphorus is an essential micromineral with a key role in cellular metabolism and tissue structure. Serum phosphorus is maintained in a homeostatic range by the intestines, bones, and kidneys. This process is coordinated by the endocrine system through the highly integrated actions of several hormones, including FGF23, PTH, Klotho, and 1,25D. The excretion kinetics of the kidney after diet phosphorus load or the serum phosphorus kinetics during hemodialysis support that there is a "pool" for temporary phosphorus storage, leading to the maintenance of stable serum phosphorus levels. Phosphorus overload refers to a state where the phosphorus load is higher than is physiologically necessary. It can be caused by a persistently high-phosphorus diet, renal function decline, bone disease, insufficient dialysis, and inappropriate medications, and includes but is not limited to hyperphosphatemia. Serum phosphorus is still the most commonly used indicator of phosphorus overload. Trending phosphorus levels to see if they are chronically elevated is recommended instead of a single test when judging phosphorus overload. Future studies are needed to validate the prognostic role of a new marker or markers of phosphorus overload.

Distinct phenotypes of kidney transplant recipients aged 80 years or older in the USA by machine learning consensus clustering

Objectives

This study aimed to identify distinct clusters of very elderly kidney transplant recipients aged ≥80 and assess clinical outcomes among these unique clusters.

Design

Cohort study with machine learning (ML) consensus clustering approach.

Setting and participants

All very elderly (age ≥80 at time of transplant) kidney transplant recipients in the Organ Procurement and Transplantation Network/United Network for Organ Sharing database database from 2010 to 2019.

Main outcome measures

Distinct clusters of very elderly kidney transplant recipients and their post-transplant outcomes including death-censored graft failure, overall mortality and acute allograft rejection among the assigned clusters.

Results

Consensus cluster analysis was performed in 419 very elderly kidney transplant and identified three distinct clusters that best represented the clinical characteristics of very elderly kidney transplant recipients. Recipients in cluster 1 received standard Kidney Donor Profile Index (KDPI) non-extended criteria donor (ECD) kidneys from deceased donors. Recipients in cluster 2 received kidneys from older, hypertensive ECD deceased donors with a KDPI score ≥85%. Kidneys for cluster 2 patients had longer cold ischaemia time and the highest use of machine perfusion. Recipients in clusters 1 and 2 were more likely to be on dialysis at the time of transplant (88.3%, 89.4%). Recipients in cluster 3 were more likely to be preemptive (39%) or had a dialysis duration less than 1 year (24%). These recipients received living donor kidney transplants. Cluster 3 had the most favourable post-transplant outcomes. Compared with cluster 3, cluster 1 had comparable survival but higher death-censored graft failure, while cluster 2 had lower patient survival, higher death-censored graft failure and more acute rejection.

Conclusions

Our study used an unsupervised ML approach to cluster very elderly kidney transplant recipients into three clinically unique clusters with distinct post-transplant outcomes. These findings from an ML clustering approach provide additional understanding towards individualised medicine and opportunities to improve care for very elderly kidney transplant recipients.

Survival Rates in Elderly Patients on Continuous Ambulatory Peritoneal Dialysis

Purpose

The present study aimed at evaluating the survival rate, its associated factors, and the causes of death in elderly patients undergoing continuous ambulatory peritoneal dialysis (CAPD) in Vietnam.

Patients and Methods

This is a retrospective, observational study conducted among patients aged ≥65 years who underwent CAPD at Thong Nhat Hospital, Ho Chi Minh City, Vietnam, from April 2012 to December 2020. The Kaplan-Meier method was used to calculate the cumulative survival rate, and the Log rank test was used to analyze the factors associated with the survival rate of patients.

Results

This study enrolled a total of 68 patients with a mean age of 71.93 ± 7.44 years at the initiation of CAPD. The most common complication among kidney failure patients was diabetic nephropathy (39.71%). The rate of concomitant cardiovascular diseases was 58.82%. The average survival rate was 45.59 ± 4.01 months. Peritonitis was the most common factor causing death (31.25%), followed by cardiovascular diseases (28.12%) and malnutrition (25%). The factors that impacted the survival rate included concomitant cardiovascular diseases, low serum albumin (<35 g/dL), and an indication of CAPD due to exhausted vascular access for hemodialysis at baseline. The main factor associated with a shorter survival time was concomitant cardiovascular diseases.

Conclusion

It is necessary to improve the survival time beyond 5 years for elderly patients undergoing CAPD, especially for those with concomitant cardiovascular diseases. Besides the prevention of peritonitis, adequate measures to protect from cardiovascular diseases and malnutrition will reduce the mortality rate in patients on CAPD.

Association between physical activity and risk of renal function decline and mortality in community-dwelling older adults: a nationwide population-based cohort study

BACKGROUND

Physical activity (PA) is an important risk factor associated with health outcomes. However, the relationship between PA and kidney function decline in older adults remains unclear. We examined the influence of PA on kidney function decline and mortality in community-dwelling older adults.

METHODS

Adults aged ≥ 65 years with an estimated glomerular filtration rate (eGFR) > 60 mL/min/1.73 m² who had available health checkup data from 2009 to 2010 were included. The cohort was followed annually through December 2015 for anthropometric, sociodemographic, and medical information including outcomes and biennially for laboratory information from the health checkup. We divided these patients into three groups according to self-reported PA (Inactive group: no leisure-time PA, Active group: vigorous activity for at least 80 min/week or a sum of moderate-intensity activity and walking for at least 300 min/week, Low-active group: level of PA between the definitions of the other two groups). Associations between the intensity of PA and death, cardiovascular death, and ≥ 50% eGFR decline were investigated.

RESULTS

Among 102,353 subjects, 32,984 (32.23%), 54,267 (53.02%), and 15,102 (14.75%) were classified into the inactive, low-active, and active groups, respectively. The active group was younger, contained a higher proportion of men, and had higher frequencies of hypertension, diabetes mellitus, drinking, and smoking than the other groups. The active group had significantly lower incidence rates of mortality, cardiovascular mortality, and kidney function decline than the other groups (all p < 0.001). The active group also showed lower all-cause (hazard ratio [HR], 0.76; 95% confidence interval [CI], 0.70-0.82) and cardiovascular mortality (HR, 0.64; 95% CI, 0.53-0.78) and protection against ≥ 50% eGFR decline (HR, 0.81; 95% CI, 0.68-0.97) compared with the inactive group in the fully adjusted Cox proportional hazards regression model.

CONCLUSIONS

High PA was an independent modifiable lifestyle factor for reducing mortality and protecting against declines in kidney function in older adults.

How useful is kidney biopsy for the management of glomerulopathies in the elderly?

BACKGROUND

The use of kidney biopsy in elderly individuals is still matter of discussion. The purpose of this study is to assess the utility of kidney biopsy for the management of glomerulopathies in an Eastern European cohort, targeting patients older than 65 years.

METHODS

This retrospective study included 875 adults (147 older than 65 years), with biopsy-proven glomerulopathies, followed up for 71.1 (95% CI 68.2-73.9) months. The primary endpoint was chronic renal replacement therapy initiation. Statistical evaluation was performed with IBM SPSS software version 20, Analyse-it, and SAS Studio. The Kaplan-Meier method was used to estimate the time to death and the log-rank test was used for comparisons. The multivariate Cox proportional hazard analysis was used to evaluate the risk of death.

RESULTS

Secondary glomerulopathies were more frequent in patients aged > 65 years (52.4% vs. 41.9%, p = 0.004). Membranous nephropathy and amyloidosis were the most frequent primary and secondary glomerulopathies in this age group. Kidney biopsy complications were low (< 4%) in both age groups. In 42% of the elderly, the result of biopsy guided the immunosuppressive therapy. While the all-cause mortality rate was higher (OR 4.2; 95% CI 2.7-6.7; p < 0.0001) in elderly individuals, the rate of renal replacement therapy initiation was similar (31.3 vs 26%; p = 0.1) in both age groups. In the competitive risk analysis, kidney survival was similar irrespective of age [CIF 0.4 (95% CI 0.26-0.53) vs. 0.34 (95% CI 0.28-0.39), p = 0.08]. However, after adjusting for the confounding factors, younger age was associated with an increased risk of renal replacement therapy (HR = 1.57, p = 0.01), along with secondary glomerulopathies.

CONCLUSION

The diagnosis of an underlying glomerulopathy guided the therapy in almost one-half of the elderly patients who underwent a kidney biopsy, provided important prognostic information and had a low complications rate; kidney biopsy may therefore be considered a safe, reliable procedure in the management of glomerulopathies, even in patients over 65 years of age.

Interferon-gamma release assays for diagnosis of latent TB infection in chronic kidney diseases and dialysis patients

Introduction

Patients with chronic kidney disease (CKD), especially end-stage kidney disease (ESKD), are at risk of developing tuberculosis (TB). The prevalence and predictors of LTBI assessed by a high-sensitivity, high-specificity test such as an interferon-gamma release assay (IGRA) has not been thoroughly explored.

Methods

All patients with CKD were prospectively recruited from September 2020 to November 2021 and retrospectively reviewed from December 2020 to November 2021. The prevalence of LTBI was determined using IGRA by CKD stage and dialysis type. Predictors of LTBI were assessed by logistic regression analysis.

Results

In total, 199 patients with CKD were enrolled (102 prospectively, 97 retrospectively). Of these, 173 patients were evaluable (mean age, 53 ± 16 years; 44% male). Ninety-five (55%) patients had ESKD and were maintained on renal replacement therapy. Overall, 39 (22.5%) patients had LTBI with a prevalence of 25.0%, 12.5%, 25.0%, 25.0%, and 24.2% among patients with CKD stage 1, 2, 3a, 3b, and ESKD, respectively (p=0.89). Among patients with ESKD, the prevalence of LTBI was higher in those on hemodialysis than in those on peritoneal dialysis (28.9% vs. 5.3%, p=0.03). In the multivariable analysis of patients with ESKD, drinking alcohol was significantly associated with LTBI (odds ratio, 8.51; 95% confidence interval, 1.24–58.38; p=0.029), and hemodialysis was marginally associated with LTBI (odds ratio, 8.14; 95% confidence interval, 0.95–69.91; p=0.056).

Conclusion

In TB-endemic settings, 20% of patients with CKD and 25% of patients with ESKD may have LTBI. Alcohol consumption and hemodialysis can help to identify high-risk patients with ESKD and potentially screen for LBTI.

Older Age is Associated With Lower Utilization of Living Donor Kidney Transplant

Introduction

Older adults (65 years or older) constitute a substantial and increasing proportion of patients with kidney failure, potentially needing kidney replacement therapy. Living donor kidney transplant (LDKT) offers superior outcomes for suitable patients of all ages. However, exploring LDKT and finding a living donor could be challenging for older adults. Here, we assessed the association between age and utilization of LDKT and assessed effect modification of key variables such as ethnicity and language.

Methods

This is a retrospective cohort study of patients with kidney failure referred for kidney transplant (KT) assessment in Toronto between January 2006 and December 2013. The association between age and having a potential living donor identified was assessed using logistic regression and the association between age and the receipt of LDKT was assessed using Cox proportional hazards models.

Results

Of the 1617 participants, 50% were middle-aged (45-64 years old), and 17% were ≥65 years old. In our final multivariable adjusted models, compared to young adults, middle-aged and older adults had lower odds of having a potential living donor identified (odds ratio [OR], 0.47; confidence interval [CI], [0.35-0.63]; OR, 0.30; CI, [0.20-0.43]; P < 0.001, for middle-aged and older adults, respectively), and were less likely to receive LDKT (hazard ratio [HR], 0.79; CI, [0.63-0.99]; P = 0.04; HR, 0.47; CI, [0.30-0.72]; P = 0.001, for middle-aged and older adults, respectively.).

Conclusion

Age is an independent predictor of receiving LDKT. Considering that nearly 90% of patients with kidney failure in Canada are >45 years of age, these results point to important and potentially modifiable age-related barriers to LDKT.

Insights into Cognitive Brain Health in Chronic Kidney Disease

Cognitive impairment and Chronic Kidney Disease (CKD) are common in older adults. With advances in medicine, the average lifespan is expected to increase, further increasing the prevalence of both conditions. The mechanisms underlying cognitive impairment in CKD are unclear. While mild-moderately low estimated glomerular filtration rate (eGFR) may not be associated with cognitive impairment, severely decreased eGFR and albuminuria do. Patients on dialysis have a high prevalence of cognitive impairment. Cognitive function improves after kidney transplantation. However, some residual cognitive deficits persist after transplantation, indicating that restoring the kidney function alone may not be enough to restore cognitive function, and other etiological factors may play a role. Albuminuria, another marker of CKD is also associated with cognitive impairment. However, albuminuria is often undiagnosed. Improving early identification and management of patients with albuminuria may be a good population-based dementia prevention strategy. Other factors associated with cognitive impairment in CKD include anemia and other metabolic derangements commonly observed in CKD. In this article, we reviewed the prevalence of cognitive impairment in CKD, the potential mechanisms underlying cognitive impairment in CKD, andthecurrent evidence on the association between cognitive impairment and eGFR and albuminuria.

Mild to moderate decrease in eGFR and cognitive decline in older adults

BACKGROUND

Whether mild to moderately low estimated glomerular filtration rate (eGFR) is associated with cognitive decline in older adults is not clear. We evaluated changes in cognition in relation to baseline eGFR in older adults participating in the Alzheimer's Disease Neuroimaging Initiative (ADNI).

METHODS

This is a longitudinal secondary analysis of an established observational cohort. We used data from the ADNI, an National Institutes of Health-funded, multicenter longitudinal observational study that includes participants with and without cognitive impairment who were administered a comprehensive battery of neuropsychological tests every 6 months. We related the Chronic Kidney Disease Epidemiology Collaboration eGFR with previously validated cognition composite scores for memory (ADNI-Mem) and executive function (ADNI-EF) in multivariable linear regression analysis adjusted for age, sex, race and level of education.

RESULTS

A total of 1127 ADNI participants (mean age 74 ± 7 years, 57% men, 97% Caucasian, mean follow-up 6 ± 2.6 years) were included in the analysis. The mean baseline eGFR was 76 ± 19 mL/min/1.73 m2, with 6% with eGFR <45, 22% with eGFR 45-<60, 51% with eGFR 60-90 and 21% with eGFR >90 mL/min/1.73 m2 at baseline. Both ADNI-Mem and ADNI-EF scores declined over time. In the multivariable linear regression model, older age (β = -0.117, P = 0.01), female sex (β = 0.312, P < 0.001) and lower education (β = 0.079, P < 0.001) were associated with a decline in ADNI-Mem scores, whereas baseline eGFR (each 10 mL/min/1.73 m2 change) was not {β = -0.03 [confidence interval (CI) -0.06-0.001], P = 0.11}. Similarly, older age (β = -0.278, P < 0.001) and lower education (β = 0.099, P < 0.001) were associated with a decline in ADNI-EF scores, whereas baseline eGFR was not [β = 0.004 (95% CI -0.04-0.04), P = 0.84].

CONCLUSIONS

In this cohort from the ADNI study, there was no association between baseline eGFR and cognitive decline in older adults with mild to moderately low eGFR.

Differentiated kidney tubular cell-derived extracellular vesicles enhance maturation of tubuloids

The prevalence of end-stage kidney disease (ESKD) is rapidly increasing with the need for regenerative therapies. Adult stem cell derived kidney tubuloids have the potential to functionally mimic the adult kidney tubule, but still lack the expression of important transport proteins needed for waste removal. Here, we investigated the potential of extracellular vesicles (EVs) obtained from matured kidney tubular epithelial cells to modulate in vitro tubuloids functional maturation. We focused on organic anion transporter 1 (OAT1), one of the most important proteins involved in endogenous waste excretion. First, we show that EVs from engineered proximal tubule cells increased the expression of several transcription factors and epithelial transporters, resulting in improved OAT1 transport capacity. Next, a more in-depth proteomic data analysis showed that EVs can trigger various biological pathways, including mesenchymal-to-epithelial transition, which is crucial in the tubular epithelial maturation. Moreover, we demonstrated that the combination of EVs and tubuloid-derived cells can be used as part of a bioartificial kidney to generate a tight polarized epithelial monolayer with formation of dense cilia structures. In conclusion, EVs from kidney tubular epithelial cells can phenotypically improve in vitro tubuloid maturation, thereby enhancing their potential as functional units in regenerative or renal replacement therapies.

Serum bicarbonate levels and gait abnormalities in older adults: a cross-sectional study

Metabolic acidosis is associated with impaired physical function in patients with chronic kidney disease (CKD) and older adults. However, whether acidosis is associated with gait abnormalities has received little attention. In a cohort of 323 community-dwelling adults ≥ 65 years old who underwent quantitative gait analysis, we examined associations of serum bicarbonate with eight individual gait variables. After multivariable adjustment, participants in the lowest bicarbonate tertile (< 25 mEq/L) had 8.6 cm/s slower speed (95% confidence interval [CI] 3.2–13.9), 7.9 cm shorter stride length (95% CI 3.5–12.2), and 0.03 s longer double support time (95% CI 0.002–0.1) compared with those in the middle tertile (25–27 mEq/L). Furthermore, lower bicarbonate levels were associated with more severe gait abnormalities in a graded manner. After further adjustment for possible mediating factors, associations were attenuated but remained significant. Among participants with CKD, associations were of similar or greater magnitude compared with those without CKD. Factor analysis was performed to synthesize the individual gait variables into unifying domains: among the pace, rhythm, and variability domains, lower serum bicarbonate was associated with worse performance in pace. In sum, lower serum bicarbonate was independently associated with worse performance on several quantitative measures of gait among older adults.

The Burden of Chronic Kidney Disease in Asia, 1990-2019: Examination of Estimates from Global Burden of Disease 2019 Study

BACKGROUND

Chronic Kidney Disease (CKD) is a global public health issue, with Asia accounting for one of the highest CKD prevalence worldwide. This study examines the burden of CKD in Asian continent in the last three decades.

DATA AND METHODS

The estimates of age, sex and year wise burden of CKD for forty-nine countries in Asia for 1990 to 2019 were procured from the Global Burden of Disease 2019 study.

FINDINGS

In 2019, there were 9.8 million [9.0 - 10.6 million] new cases and 763,024 [696,050 - 823,829] deaths due to CKD in Asia. Between 1990 and 2019, CKD prevalence doubled from 202.4 million [186.5-219.1 million] to 431.2 [400.3-462.0 million]. Although age-standardized incidence rate (ASIR) of CKD increased from 170.6 [156.7 - 186.2] in 1990 to 206.3 [190.4 - 223.4] per 100,000 person-years in 2019, the age-standardized mortality rate (ASMR) witnessed a modest reduction from 18.4/100,000 [17.0 - 20.1] to 17.3/100,000 [15.7 - 18.7]. In 2019, the ASIR spanned from 141.9 /100,000 [126.2 - 159.2] in Tajikistan to 561.4/100,000 [524.6 - 598.6] in Saudi Arabia, and ASMR varied from 8.9/100,000 [7.2-9.8] in Japan to Saudi Arabia (52.9[42.8-63.1]). Between 1990 and 2019, absolute count of CKD incident cases, deaths, prevalent cases and DALYs increased 100% or more in 48/49, 32/49, 43/49 and 23/49 countries, respectively.

INTERPRETATION

CKD is widespread in the Asian region, with an alarming burden in resource-constrained countries. Strategies such as promoting awareness, screening among high-risk individuals, provision of cost-effective therapies, and increased healthcare coverage could help deal with the CKD epidemic in Asia.

Urine-Derived Stem Cell-Secreted Klotho Plays a Crucial Role in the HK-2 Fibrosis Model by Inhibiting the TGF-β Signaling Pathway

Renal fibrosis is an irreversible and progressive process that causes severe dysfunction in chronic kidney disease (CKD). The progression of CKD stages is highly associated with a gradual reduction in serum Klotho levels. We focused on Klotho protein as a key therapeutic factor against CKD. Urine-derived stem cells (UDSCs) have been identified as a novel stem cell source for kidney regeneration and CKD treatment because of their kidney tissue-specific origin. However, the relationship between UDSCs and Klotho in the kidneys is not yet known. In this study, we discovered that UDSCs were stem cells that expressed Klotho protein more strongly than other mesenchymal stem cells (MSCs). UDSCs also suppressed fibrosis by inhibiting transforming growth factor (TGF)-β in HK-2 human renal proximal tubule cells in an in vitro model. Klotho siRNA silencing reduced the TGF-inhibiting ability of UDSCs. Here, we suggest an alternative cell source that can overcome the limitations of MSCs through the synergetic effect of the origin specificity of UDSCs and the anti-fibrotic effect of Klotho.

The IL-18/IL-18R1 signalling axis: Diagnostic and therapeutic potential in hypertension and chronic kidney disease

Chronic kidney disease (CKD) is inherently an inflammatory condition, which ultimately results in the development of end stage renal disease or cardiovascular events. Low-grade inflammatory diseases such as hypertension and diabetes are leading causes of CKD. Declines in renal function correlate with elevated circulating pro-inflammatory cytokines in patients with these conditions. The inflammasome is an important inflammatory signalling platform that has been associated with low-grade chronic inflammatory diseases. Notably, activation and assembly of the inflammasome causes the auto cleavage of pro-caspase-1 into its active form, which then processes the pro-inflammatory cytokines pro-interleukin (IL)-1β and pro-IL-18 into their active forms. Currently, the nod-like receptor protein 3 (NLRP3) inflammasome has been implicated in the development of CKD in pre-clinical and clinical settings, and the ablation or inhibition of inflammasome components have been shown to be reno-protective in models of CKD. While clinical trials have demonstrated that neutralisation of IL-1β signalling by the drug anakinra lowers inflammation markers in haemodialysis patients, ongoing preclinical studies are showing that this ability to attenuate disease is limited in progressive models of kidney disease. These results suggest a potential predominant role for IL-18 in the development of CKD. This review will discuss the role of the inflammasome and its pro-inflammatory product IL-18 in the development of renal fibrosis and inflammation that contribute to the pathophysiology of CKD. Furthermore, we will examine the potential of the IL-18 signalling axis as an anti-inflammatory target in CKD and its usefulness as diagnostic biomarker to predict acute kidney injury.

Accelerated epigenetic aging and inflammatory/immunological profile (ipAGE) in patients with chronic kidney disease

Chronic kidney disease (CKD) is defined by a reduced estimated glomerular filtration rate (eGFR). This failure can be related to a phenotype of accelerated aging. In this work, we considered 76 patients with end-stage renal disease (ESRD) and 83 healthy controls. We concomitantly evaluated for the first time two measures that can be informative of the rate of aging, i.e., whole blood DNA methylation using the Illumina Infinium EPIC array and plasma levels of a selection of inflammatory/immunological proteins using multiplex immunoassays. First of all, we demonstrated accelerated aging in terms of the most common epigenetic age estimators in CKD patients. Moreover, we developed a new clock/predictor of age based on the inflammatory/immunological profile (ipAGE) and identified the inflammatory/immunological biomarkers differentially expressed between cases and controls. IpAGE appeared to be more sensitive than epigenetic clocks in quantifying the accelerated aging phenotype of ESRD patients. Interestingly, we did not find any correlation between the age acceleration evaluated according to the epigenetic clocks and ipAGE in either the ESRD group or the control group. On the whole, our data show a consistent accelerated aging phenotype in ESRD patients, which is better appreciated by quantifying the underlying inflammatory processes (inflammaging) by ipAGE than by using epigenetic clocks.

Cost of End-of-Life Inpatient Encounters in Patients with Chronic Kidney Disease in the United States: A Report from the DISCOVER CKD Retrospective Cohort

Introduction

Real-world data reporting healthcare resource utilisation and costs associated with end-of-life care for patients with chronic kidney disease (CKD) are limited. We examined length of hospitalisation and costs associated with end-of-life inpatient encounters using retrospective data from DISCOVER CKD.

Methods

Data on inpatient encounters for patients with CKD aged ≥ 18 years between January 2016 and March 2020 were extracted from the US Premier Hospital Database. Encounters ending in death were identified and grouped by reason for the encounter, using the International Classification of Diseases, Tenth Revision, and by their insurance coverage. Encounters were evaluated overall and stratified according to cardiovascular (CV), kidney failure and infection-related reasons, and by their coverage by commercial, Medicaid, Medicare or other insurers. Length of hospitalisation and total costs were calculated for encounters.

Results

Among 237,734 encounters ending in death, the mean [standard deviation (SD)] age was 74.2 (12.4) years, and 45.3% of patients were female. In total, 25,118, 4210 and 76,307 encounters were classified as relating to CV reasons, kidney failure and infection, respectively. Among all encounters, the mean (SD) length of hospitalisation ranged from 9.1 (11.2) (Medicare) to 12.8 (18.4) (Medicaid) days. Across insurers, encounters related to kidney failure were associated with the longest hospitalisations compared with CV and infection [mean range (days): 10.7–15.9 vs. 7.5–10.5 and 8.7–12.7, respectively]. The median [interquartile range (IQR)] total cost of any inpatient encounter was $17,057 ($8040–35,873). Kidney failure-related encounters had higher costs compared with CV and infection [median (IQR), $18,469 ($8673–38,315) vs. $17,503 ($7766–39,693) and $16,403 ($7762–34,910), respectively]. Medicaid-covered encounters had the highest costs of all insurers [median (IQR), $16,189 ($7725–33,443)].

Conclusions

Among patients with CKD, end-of-life encounters were most frequently related to infection. Encounters relating to kidney failure incurred the highest costs.

Trial registration

ClinicalTrials.gov identifier: NCT04034992.

Graphical Abstract

Supplementary Information

The online version contains supplementary material available at 10.1007/s12325-021-02010-3.

Survival of Older Patients With Advanced CKD Managed Without Dialysis: A Narrative Review

Shared decision making is important when deciding the appropriateness of dialysis for any individual, particularly for older patients with advanced chronic kidney disease who have high mortality. Emerging evidence suggests that patients with advanced age, high comorbidity burden, and poor functional status may not have any survival advantage on dialysis compared with those on a conservative kidney management pathway. The purpose of this narrative review is to summarize the existing studies on the survival of older patients with stage 4 or 5 chronic kidney disease managed with or without dialysis and to evaluate the factors that may influence mortality in an effort to assist clinicians with shared decision making. Median survival estimates of conservative kidney management patients are widely varied, ranging from 1-45 months with 1-year survival rates of 29%-82%, making it challenging to provide consistent advice to patients. In existing cohort studies, the selected group of patients on dialysis generally survives longer than the conservative kidney management cohort. However, in patients with advanced age (aged ≥80 years), high comorbidity burden, and poor functional status, the survival benefit conferred by dialysis is no longer present. There is an overall paucity of data, and the variability in outcomes reflect the heterogeneity of the existing studies; further prospective studies are urgently needed.

Using a Simple Prescription Gap to Determine Warfarin Discontinuation Can Lead to Substantial Misclassification

BACKGROUND

Warfarin remains widely used and a key comparator in studies of other direct oral anticoagulants. As longer-than-needed warfarin prescriptions are often provided to allow for dosing adjustments according to international normalized ratios (INRs), the common practice of using a short allowable gap between dispensings to define warfarin discontinuation may lead to substantial misclassification of warfarin exposure. We aimed to quantify such misclassification and determine the optimal algorithm to define warfarin discontinuation.

METHODS

We linked Medicare claims data from 2007 to 2014 with a multicenter electronic health records system. The study cohort comprised patients ≥65 years with atrial fibrillation and venous thromboembolism initiating warfarin. We compared results when defining warfarin discontinuation by (1) different gaps (3, 7, 14, 30, and 60 days) between dispensings and (2) having a gap ≤60 days or bridging larger gaps if there was INR ordering at least every 42 days (60_INR). Discontinuation was considered misclassified if there was an INR ≥2 within 7 days after the discontinuation date.

RESULTS

Among 3,229 patients, a shorter gap resulted in a shorter mean follow-up time (82, 95, 117, 159, 196, and 259 days for gaps of 3, 7, 14, 30, 60, and 60_INR, respectively; p < 0.001). Incorporating INR (60_INR) can reduce misclassification of warfarin discontinuation from 68 to 4% (p < 0.001). The on-treatment risk estimation of clinical endpoints varied significantly by discontinuation definitions.

CONCLUSION

Using a short gap between warfarin dispensings to define discontinuation may lead to substantial misclassification, which can be improved by incorporating intervening INR codes.

The Prevalence of Potential Drug-Drug Interactions in CKD-A Retrospective Observational Study of Cerrahpasa Nephrology Unit

Background and Objectives: Chronic kidney disease (CKD) is usually linked with polypharmacy and patients are invariably at risk of complex medication regimens. The present study was designed to estimate the potential drug-drug interactions (pDDIs) through the prescription patterns provided to patients of the Nephrology Transplant Unit of Cerrahpasa Medical Faculty patients. Materials and Methods: 96 patients were included in the study. pDDIs among every combination of the prescribed drug were analyzed using the Thomson Reuters Micromedex. Results: We found 149 pDDIs making 2.16 interactions per prescription with incidence rates of 69.7%. Approximately 4.1% of interactions were of significant severity, 75.1% moderate severity, and 20.8% were classified as minor pDDIs. The most frequent interactions were found between iron and aluminum, calcium or magnesium-containing products (21.37%), calcium channel blockers and beta-blockers (8.96%); and aspirin and aluminum, calcium, or magnesium-containing products (7.58%). We identified 42 drug pairs with probability of clinical significance. The most commonly reported clinical outcomes of the pDDIs were hypo- or hypertension (39.24%), decreased drug efficacy (24.05%), and arrhythmia (9.49%). Aluminum, calcium, or magnesium-containing drug products (33.10%) constituted the primary class of drugs involved in interactions. Conclusions: This study showed pharmacodynamics (49%), pharmacokinetics (42.94%) interactions, polypharmacy and gender as determinant of pDDIs. A comprehensive multicenter research is required to decrease the morbidity and ease the state burden.

Applying A Biopsychosocial Framework to Achieve Durable Behavior Change in Kidney Disease

Chronic disease self-management is the establishment and maintenance of behaviors needed to be an active participant in one's health care and experience the best health outcomes. Kidney disease self-management behaviors to slow disease progression include engaging in exercise or physical activity; adhering to a diet low in sodium, potassium, and phosphorus; monitoring laboratory parameters; managing complex medication regimens; coping with disease-related emotional distress; and communicating effectively with providers. Durable behavior change has been difficult to achieve in kidney disease, in part because of an incomplete understanding of the multilevel factors determining chronic disease self-management in this patient group. The biopsychosocial model of chronic illness care posits that an individual's health outcomes result from biological, psychological, social, and environmental factors as part of a multilevel systems hierarchy. Although this theoretical model has been used to comprehensively identify factors driving self-management in other chronic conditions, it has been applied infrequently to behavioral interventions in kidney disease. In this scoping review, we apply the biopsychosocial model of health to identify individual, interpersonal, and systems-level drivers of kidney disease self-management behaviors. We further highlight factors that may serve as novel, impactful targets of theory-based behavioral interventions to understand and sustain behavior change in kidney disease.

Low Dose Lithium Treatment of Behavioral Complications in Alzheimer's Disease: Lit-AD Randomized Clinical Trial

BACKGROUND

A case series suggested efficacy for lithium to treat agitation in dementia, but no placebo-controlled trials have been conducted.

OBJECTIVES

To evaluate low-dose lithium treatment of agitation in Alzheimer's disease (AD).

METHOD

In a four-site trial, patients with AD and agitation/aggression score ≥4 on the Neuropsychiatric Inventory (NPI) were randomized, double-blind, to lithium carbonate 150-600 mg daily or placebo for 12 weeks. Primary efficacy outcome was change in NPI agitation/aggression; secondary efficacy outcome was treatment response (30% reduction in NPI score for agitation/aggression plus psychosis and a Clinical Global Impression (CGI) score of much or very much improved). Safety profile of lithium was assessed.

RESULTS

Fifty-eight of 77 patients (75.3%) completed the trial. In linear mixed effects model analyses, lithium was not significantly superior to placebo for agitation/aggression. Proportion of responders was 31.6% on lithium and 17.9% on placebo (χ²=1.26, p = 0.26). Moderate or marked improvement (CGI) was greater on lithium (10/38=36.8%) than placebo (0/39=0%, Fisher's exact test p <0.001). In exploratory analyses, improvement on lithium was greater than placebo on NPI delusions and irritability/lability (p's<0.05). Lithium showed greater reduction than placebo in patients with high Young Mania Rating Scale scores (β=5.06; 95%CI,1.18 to 8.94, p = 0.01). Oral dose and serum levels demonstrated similar associations with efficacy outcomes. Lithium did not differ significantly from placebo on safety outcomes.

CONCLUSIONS

Low-dose lithium was not efficacious in treating agitation but was associated with global clinical improvement and excellent safety. A larger trial may be warranted of likely lithium-responsive behavioral symptoms that overlap with mania.

Sex Differences in Fecal Microbiota Correlation With Physiological and Biochemical Indices Associated With End-Stage Renal Disease Caused by Immunoglobulin a Nephropathy or Diabetes

This study investigated the sex-specific differences in the correlation between intestinal microbiota and end-stage renal disease. Here, we compared the differences in the gut microbiota of male and female healthy controls (HC) and patients with end-stage renal disease (ESRD) caused by immunoglobulin A (IgA) nephropathy (ESRD-IgAN) or type-2 diabetes mellitus (ESRD-T2DM) using high-throughput sequencing of the 16S rRNA gene. We also analyzed the correlation between gut microbiota and clinical immune indicators. We assigned 8, 10, 5, 7, 11, and 20 volunteers to female HC, ESRD-IgAN, and ESRD-T2DM, and male HC, ESRD-IgAN, and ESRD-T2DM, respectively. The results showed sex-specific differences in both physiological and biochemical indices and intestinal microbiota composition, as well as the correlation between them. The correlations between physiological and biochemical indices in men were significantly lower than those in women, especially for indices related to immunity, blood glucose, and cardiac color sonography. Urine output, lymphocyte ratio, serum albumin, blood calcium, dialysis status, serum urea nitrogen, urine protein, and diabetes significantly correlated with male fecal microbiota composition, whereas only creatinine and 2-h post-prandial blood glucose significantly correlated with female fecal microbiota composition. The top 50 dominant operational taxonomic units showed a stronger correlation with physiological and biochemical indices in samples obtained from females than from males. These differences highlight sex-specific differences in the effectiveness of ESRD prevention and treatments via regulating intestinal microbiota.

Correlates of objective sleep quality in older peritoneal dialysis patients

BACKGROUND

Sleep disturbance is a prominent concern in dialysis patients and detrimentally impacts clinical and self-reported health outcomes. This study aimed to collect sleep data from in-home actigraphy and to explore possible predictors of sleep quality in older peritoneal dialysis patients.

METHODS

This was a cross-sectional study. Peritoneal dialysis patients aged ≥60 years participated in this study. For each participant, sleep quality was assessed by analyzing the data produced by an actigraphic device worn on the wrist 24 h a day for seven consecutive days. Physical function was assessed using handgrip strength and the Timed Up and Go test. Depression was assessed using the self-reported Geriatric Depression Scale. Multiple linear regression analyses were performed to examine the factors influencing sleep efficiency and sleep time.

RESULTS

Based on data collected from 50 participants (N = 50, mean age 70.4 years, 70% male), including 333 nights of actigraphy-monitored sleep, the mean sleep efficiency was 75.5%±14.2% and the mean total sleep time 391.0 ± 99.3 min per night. Higher hemoglobin (β = 0.38, p = 0.007) and lower serum phosphorus (β = -0.30, p = 0.042) levels were significant predictors of better sleep efficiency. The only significant predictor of the total sleep time was age (β = 0.32, p = 0.021).

CONCLUSION

Older peritoneal dialysis patients had poor sleep, characterized by low sleep efficiency. Low hemoglobin and high serum phosphorus levels were predictors of poor sleep efficiency and, as such, modifiable factors for clinicians to consider when treating patients with sleep complaints.

Outcomes of Kidney Transplantation in the Elderly Recipients

Introduction:

In a developing country with a predominantly young population, the valid assumption is directed toward medical care toward the young. However, as medical technology has advanced, quality care has ensured better survival for the elderly population also. The aim of this study was to determine the clinical outcomes in elderly patients undergoing kidney transplantation.

Materials and Methods:

A retrospective analysis of 1150 patients who had undergone live related renal transplantation was done from January 2006 to December 2014. These patients were divided into two groups; Group 1: age >60 years (N = 150), Group 2: age 18–60 years (N = 1000). The clinical outcomes were compared.

Results:

The mean age in Group 1 was 69 ± 7.5 years (SD ± 7.5), and group 2 was 41 ± 8 years. In groups 1 and 2, males were 80% and 82%; death censored graft survival at 5 years was 82% and 87%; patient survival at 5 years was 86% and 94%, respectively. The incidence of biopsy-proven acute rejection was similar in both groups (11.3 vs. 10.2%, P = 0.12). Urinary tract infection was the most common infectious complication. Sepsis was the primary cause of death in both groups.

Conclusion:

In the elderly patients who underwent kidney transplantation, satisfactory graft function, and patient survival were maintained over a period of 60 months. Urinary tract infections were common, and sepsis was the most common cause of death with a surviving allograft. The acute rejection and mortality rates were comparable to the literature published from India so far.

Chronic Kidney Disease: Strategies to Retard Progression

Chronic kidney disease (CKD), defined as the presence of irreversible structural or functional kidney damages, increases the risk of poor outcomes due to its association with multiple complications, including altered mineral metabolism, anemia, metabolic acidosis, and increased cardiovascular events. The mainstay of treatments for CKD lies in the prevention of the development and progression of CKD as well as its complications. Due to the heterogeneous origins and the uncertainty in the pathogenesis of CKD, efficacious therapies for CKD remain challenging. In this review, we focus on the following four themes: first, a summary of the known factors that contribute to CKD development and progression, with an emphasis on avoiding acute kidney injury (AKI); second, an etiology-based treatment strategy for retarding CKD, including the approaches for the common and under-recognized ones; and third, the recommended approaches for ameliorating CKD complications, and the final section discusses the novel agents for counteracting CKD progression.

Brahma-related gene-1 promotes tubular senescence and renal fibrosis through Wnt/β-catenin/autophagy axis

Although accelerated cellular senescence is closely related to the progression of chronic kidney disease (CKD) and renal fibrosis, the underlying mechanisms remain largely unknown. Here, we reported that tubular aberrant expression of Brahma-related gene 1 (BRG1), an enzymatic subunit of the SWItch/Sucrose Non-Fermentable complex, is critically involved in tubular senescence and renal fibrosis. BRG1 was significantly up-regulated in the kidneys, predominantly in tubular epithelial cells, of both CKD patients and unilateral ureteral obstruction (UUO) mice. In vivo, shRNA-mediated knockdown of BRG1 significantly ameliorated renal fibrosis, improved tubular senescence, and inhibited UUO-induced activation of Wnt/β-catenin pathway. In mouse renal tubular epithelial cells (mTECs) and primary renal tubular cells, inhibition of BRG1 diminished transforming growth factor-β1 (TGF-β1)-induced cellular senescence and fibrotic responses. Correspondingly, ectopic expression of BRG1 in mTECs or normal kidneys increased p16INK4a, p19ARF, and p21 expression and senescence-associated β-galactosidase (SA-β-gal) activity, indicating accelerated tubular senescence. Additionally, BRG1-mediated pro-fibrotic responses were largely abolished by small interfering RNA (siRNA)-mediated p16INK4a silencing in vitro or continuous senolytic treatment with ABT-263 in vivo. Moreover, BRG1 activated the Wnt/β-catenin pathway, which further inhibited autophagy. Pharmacologic inhibition of the Wnt/β-catenin pathway (ICG-001) or rapamycin (RAPA)-mediated activation of autophagy effectively blocked BRG1-induced tubular senescence and fibrotic responses, while bafilomycin A1 (Baf A1)-mediated inhibition of autophagy abolished the effects of ICG-001. Further, BRG1 altered the secretome of senescent tubular cells, which promoted proliferation and activation of fibroblasts. Taken together, our results indicate that BRG1 induces tubular senescence by inhibiting autophagy via the Wnt/β-catenin pathway, which ultimately contributes to the development of renal fibrosis.

Immunosuppression Regimen Use and Outcomes in Older and Younger Adult Kidney Transplant Recipients: A National Registry Analysis

BACKGROUND

Although the population of older transplant recipients has increased dramatically, there are limited data describing the impact of immunosuppression regimen choice on outcomes in this recipient group.

METHODS

National data for US Medicare-insured adult kidney recipients (N = 67 362; 2005-2016) were examined to determine early immunosuppression regimen and associations with acute rejection, death-censored graft failure, and mortality using multivariable regression analysis in younger (18-64 y) and older (>65 y) adults.

RESULTS

The use of antithymocyte globulin (TMG) or alemtuzumab (ALEM) induction with triple maintenance immunosuppression (reference) was less common in older compared with younger (36.9% versus 47.0%) recipients, as was TMG/ALEM + steroid avoidance (19.2% versus 20.1%) and mammalian target of rapamycin inhibitor (mTORi)-based (6.7% versus 7.7%) treatments. Conversely, older patients were more likely to receive interleukin (IL)-2-receptor antibody (IL2rAb) + triple maintenance (21.1% versus 14.7%), IL2rAb + steroid avoidance (4.1% versus 1.8%), and cyclosporine-based (8.3% versus 6.6%) immunosuppression. Compared with older recipients treated with TMG/ALEM + triple maintenance (reference regimen), those managed with TMG/ALEM + steroid avoidance (adjusted odds ratio [aOR], 0.440.520.61) and IL2rAb + steroid avoidance (aOR, 0.390.550.79) had lower risk of acute rejection. Older patients experienced more death-censored graft failure when managed with Tac + antimetabolite avoidance (adjusted hazard [aHR], 1.411.782.25), mTORi-based (aHR, 1.702.142.71), and cyclosporine-based (aHR, 1.411.782.25) regimens, versus the reference regimen. mTORi-based and cyclosporine-based regimens were associated with increased mortality in both older and younger patients.

CONCLUSIONS

Lower-intensity immunosuppression regimens (eg, steroid-sparing) appear beneficial for older kidney transplant recipients, while mTORi and cyclosporine-based maintenance immunosuppression are associated with higher risk of adverse outcomes.

Hip Fracture Risk in Elderly With Non-End-Stage Chronic Kidney Disease: A Fall Related Analysis

BACKGROUND

The aim of this study was to evaluate the risk of fracture as a consequence of trauma and its association with kidney function status in a cohort of elderly patients.

METHODS

This is an observational, cross-sectional study. We evaluated all fall-related trauma of patients ≥ 65 years in the emergency department (ED) between 2016 and 2018. According to CDK-EPI formula, we stratified the study population in different stages of chronic kidney disease (CKD) for glomerular filtrate rate (GFR) ≥ 15 and < 60, not on hemodialysis. The hip fracture rate was adjusted at multivariate analysis for age, sex, comorbid conditions, and CKD status.

RESULTS

We enrolled 5620 patients: 3482 patients had GFR ≥60, 1045 had GFR ≥45 and <60, 722 had GFR ≥30 and <45, and 371 had GFR ≥15 and <30. We recorded 636 (11.3%) hip fractures. After adjusting for significant covariates (age, sex, known osteoporosis, osteoporosis therapy, anemia, and dementia), patients with GFR ≥ 45 and <60 and GFR ≥30 and <45 exhibited an increased risk of femur fracture (odds ratio 2.01 [1.36-2.97] and 1.64 [1.08-2.48], respectively). Patients with GFR ≥15 and <30 had a higher risk of fracture, although not reaching statistical significance.

CONCLUSIONS

Our study confirms that patients with non-end stage CKD have an increased risk of femur fracture after a fall. Our data supports the hypothesis that this risk could be associated with increased bone fragility in CKD patients. Active osteoporosis therapy was found to be an effective preventive factor in our cohort.

Routine use of natriuretic peptides: Lessons from a big data analysis

BACKGROUND

Natriuretic peptides have broad indications during heart failure and the detection of left ventricular dysfunction in high-risk patients. They can also be used for the diagnosis/management of other cardiac diseases. However, very little is known regarding their use in routine practice.

METHODS

We examined all biological tests performed from February 2010 to August 2015 in two districts from the French Brittany, covering 13,653 km² and including 22,265 physicians. We report the settings and conditions of N-terminal pro-B-type natriuretic peptide (NT-proBNP) measurements (the only locally natriuretic peptide available).

RESULTS

From a total of 3,606,432 tests requested in 557,650 adult (older than 20 years) patients, only 56,653 (1.6%) included at least one NT-proBNP measurement. NT-proBNP measurements gradually increased, from 9188 in 2011 to 12,938 in 2014 (P < 0.001). Most NT-proBNP tests were measured in urban laboratories (72.7%) and in private (62.9%) non-hospital/clinics laboratories; they were mostly ordered by general practitioners (66% compared with 11% by cardiologists). The number of NT-proBNP measurements increased with age up to 80-90 years, and 70.3% of tests were measured in ≥75 years patients. Creatinine and electrolytes were not associated with NT-proBNP in 15.8% and 19.7% of tests, respectively.

CONCLUSION

Among a very large cohort, we observed that natriuretic peptides remain largely undermeasured. NT-proBNP is mostly measured in elderly patients, and its interpretation may be hazardous in up to 16% of all individuals because no measurement of creatinine was associated to NT-proBNP.

The Role of Plasma Neurofilament Light Protein for Assessing Cognitive Impairment in Patients With End-Stage Renal Disease

Introduction: End-stage renal disease (ESRD) is defined as the irreversible loss of renal function, necessitating renal replacement therapy. Patients with ESRD tend to have more risk factors for cognitive impairment than the general population, including hypertension, accumulative uremic toxin, anemia, and old age. The association between these risk factors and the pathologic protein was lacking. Blood-based assays for detecting pathologic protein, such as amyloid beta (Aβ), total tau protein, and neurofilament light chain (NfL), have the advantages of being less invasive and more cost-effective for diagnosing patients with cognitive impairment. The aim of the study is to validate if the common neurologic biomarkers were different in ESRD patients and to differentiate if the specific biomarkers could correlate with specific correctable risk factors. Methods: In total, 67 participants aged >45 years were enrolled. The definition of ESRD was receiving maintenance hemodialysis for >3 months. Cognitive impairment was defined as a Mini-Mental State Examination score of <24. The participants were divided into groups for ESRD with and without cognitive impairment. The blood-based biomarkers (tau protein, Aβ1/40, Aβ1/42, and NfL) were analyzed through immunomagnetic reduction assay. Other biochemical and hematologic data were obtained simultaneously. Summary of results: The study enrolled 43 patients with ESRD who did not have cognitive impairment and 24 patients with ESRD who had cognitive impairment [Mini-Mental State Examination (MMSE): 27.60 ± 1.80 vs. 16.84 ± 6.40, p < 0.05]. Among the blood-based biomarkers, NfL was marginally higher in the ESRD with cognitive impairment group than in the ESRD without cognitive impairment group (10.41 ± 3.26 vs. 8.74 ± 2.81 pg/mL, p = 0.037). The concentrations of tau protein, amyloid β 1/42, and amyloid β 1/40 (p = 0.504, 0.393, and 0.952, respectively) were similar between the two groups. The area under the curve of NfL to distinguish cognitively impaired and unimpaired ESRD patients was 0.687 (95% confidence interval: 0.548-0.825, p = 0.034). There was no correlation between the concentration of NfL and MMSE among total population (r = -0.153, p = 0.277), patients with (r = 0.137, p = 0.583) or without cognitive impairment (r = 0.155, p = 0.333). Conclusion: Patients with ESRD who had cognitive impairment had marginally higher plasma NfL concentrations. NfL concentration was not correlated with the biochemical parameters, total MMSE among total population or individual groups with or without cognitive impairment. The concentrations of Aβ1/40, Aβ1/42, and tau were similar between the groups.