Protein Biomarkers and Major Cardiovascular Events in Older People With Advanced CKD: The European Quality (EQUAL) Study.

Rationale & Objective: Cardiovascular disease is the leading cause of morbidity and mortality in chronic kidney disease (CKD). We investigated 184 inflammatory and cardiovascular proteins to determine their potential as biomarkers for major cardiovascular events (MACEs). Study Design: The European Quality (EQUAL) is an observational cohort study that enrolled people aged ≥65 years with an estimated glomerular filtration rate ≤20 mL/min/1.73 m2. Setting & Participants: Recruited participants were split into the discovery (n = 611) and replication cohorts (n = 292). Exposure: Levels of 184 blood proteins were measured at the baseline visit, and each protein was analyzed individually. Outcome: MACE. Analytical Approach: Cox proportional hazard models adjusted for age, sex, estimated glomerular filtration rate, previous MACE, and country were used to determine the risk of MACE. Proteins with false discovery rate adjusted P values of <0.05 in the discovery cohort were tested in the replication cohort. Sensitivity analyses were performed by adjusting for traditional risk factors, CKD-specific risk factors, and level of proteinuria and segregating atherosclerotic and nonatherosclerotic MACE. Results: During a median follow-up of 2.9 years, 349 people (39%) experienced a MACE. Forty-eight proteins were associated with MACE in the discovery cohort; 9 of these were reproduced in the replication cohort. Three of these proteins maintained a strong association with MACE after adjustment for traditional and CKD-specific risk factors and proteinuria. Tenascin (TNC), fibroblast growth factor-23 (FGF-23), and V-set and immunoglobulin domain-containing protein 2 (VSIG2) were associated with both atherosclerotic and nonatherosclerotic MACE. All replicated proteins except carbonic anhydrase 1 and carbonic anhydrase 3 were associated with nonatherosclerotic MACE. Limitations: Single protein concentration measurements and limited follow-up time. Conclusions: Our findings corroborate previously reported relationships between FGF-23, vascular cell adhesion protein-1, TNC, and placental growth factor with cardiovascular outcomes in CKD. We identify 5 proteins not previously linked with MACE in CKD that may be targets for future therapies. Plain-Language Summary: Kidney disease increases the risk of heart disease, stroke, and other vascular conditions. Blood tests that predict the likelihood of these problems may help to guide treatment, but studies are needed in people with kidney disease. We analyzed blood tests from older people with kidney disease, looking for proteins associated with higher risk of these conditions. Nine proteins were identified, of which 3 showed a strong effect after all other information was considered. This work supports previous research regarding 4 of these proteins and identifies 5 additional proteins that may be associated with higher risk. Further work is needed to confirm our findings and to determine whether these proteins can be used to guide treatment.

Association between CKD-MBD and mortality in older patients with advanced CKD-results from the EQUAL study.

BACKGROUND: Chronic kidney disease-mineral and bone disorder (CKD-MBD) is a common complication of CKD; it is associated with higher mortality in dialysis patients, while its impact in non-dialysis patients remains mostly unknown. We investigated the associations between parathyroid hormone (PTH), phosphate and calcium (and their interactions), and all-cause, cardiovascular (CV) and non-CV mortality in older non-dialysis patients with advanced CKD. METHODS: We used data from the European Quality study, which includes patients aged ≥65 years with estimated glomerular filtration rate ≤20 mL/min/1.73 m2 from six European countries. Sequentially adjusted Cox models were used to assess the association between baseline and time-dependent CKD-MBD biomarkers and all-cause, CV and non-CV mortality. Effect modification between biomarkers was also assessed. RESULTS: In 1294 patients, the prevalence of CKD-MBD at baseline was 94%. Both PTH [adjusted hazard ratio (aHR) 1.12, 95% confidence interval (CI) 1.03-1.23, P = .01] and phosphate (aHR 1.35, 95% CI 1.00-1.84, P = .05), but not calcium (aHR 1.11, 95% CI 0.57-2.17, P = .76), were associated with all-cause mortality. Calcium was not independently associated with mortality, but modified the effect of phosphate, with the highest mortality risk found in patients with both hypercalcemia and hyperphosphatemia. PTH level was associated with CV mortality, but not with non-CV mortality, whereas phosphate was associated with both CV and non-CV mortality in most models. CONCLUSIONS: CKD-MBD is very common in older non-dialysis patients with advanced CKD. PTH and phosphate are independently associated with all-cause mortality in this population. While PTH level is only associated with CV mortality, phosphate seems to be associated with both CV and non-CV mortality.

Clinical and patient-reported trajectories at end-of-life in older patients with advanced CKD.

BACKGROUND: We explore longitudinal trajectories of clinical indicators, patient-reported outcomes, and hospitalizations, in the years preceding death in a population of older patients with advanced chronic kidney disease (CKD). METHODS: The EQUAL study is a European observational prospective cohort study with an incident eGFR <20 ml/min per 1.73 m2 and ≥65 years of age. The evolution of each clinical indicator was explored using generalized additive models during the 4 years preceding death. RESULTS: We included 661 decedents with a median time to death of 2.0 years (IQR 0.9-3.2). During the years preceding death, eGFR, Subjective Global Assessment score, and blood pressure declined, with accelerations seen at 6 months preceding death. Serum hemoglobin, hematocrit, cholesterol, calcium, albumin, and sodium values declined slowly during follow-up, with accelerations observed between 6 and 12 months preceding death. Physical and mental quality of life declined linearly throughout follow-up. The number of reported symptoms was stable up to 2 years prior to death, with an acceleration observed at 1 year prior to death. The rate of hospitalization was stable at around one hospitalization per person year, increasing exponentially at 6 months preceding death. CONCLUSIONS: We identified clinically relevant physiological accelerations in patient trajectories that began ∼6 to 12 months prior to death, which are likely multifactorial in nature, but correlate with a surge in hospitalizations. Further research should focus on how to effectively use this knowledge to inform patient and family expectations, to benefit the planning of (end-of-life) care, and to establish clinical alert systems.

The association between TMAO, CMPF, and clinical outcomes in advanced chronic kidney disease: results from the European QUALity (EQUAL) Study.

BACKGROUND: Trimethylamine N-oxide (TMAO), a metabolite from red meat and fish consumption, plays a role in promoting cardiovascular events. However, data regarding TMAO and its impact on clinical outcomes are inconclusive, possibly due to its undetermined dietary source. OBJECTIVES: We hypothesized that circulating TMAO derived from fish intake might cause less harm compared with red meat sources by examining the concomitant level of 3-carboxy-4-methyl-5-propyl-2-furanpropionate (CMPF), a known biomarker of fish intake, and investigated the association between TMAO, CMPF, and outcomes. METHODS: Patients were recruited from the European QUALity (EQUAL) Study on treatment in advanced chronic kidney disease among individuals aged ≥65 y whose estimated glomerular filtration rate (eGFR) had dropped for the first time to ≤20 mL/min per 1.73 m2 during the last 6 mo. The association between TMAO, CMPF, and outcomes including all-cause mortality and kidney replacement therapy (KRT) was assessed among 737 patients. Patients were further stratified by median cutoffs of TMAO and CMPF, suggesting high/low red meat and fish intake. RESULTS: During a median of 39 mo of follow-up, 232 patients died. Higher TMAO was independently associated with an increased risk of all-cause mortality (multivariable HR: 1.46; 95% CI: 1.17, 1.83). Higher CMPF was associated with a reduced risk of both all-cause mortality (HR: 0.79; 95% CI: 0.71, 0.89) and KRT (HR: 0.80; 95% CI: 0.71, 0.90), independently of TMAO and other clinically relevant confounders. In comparison to patients with low TMAO and CMPF, patients with low TMAO and high CMPF had reduced risk of all-cause mortality (adjusted HR: 0.49; 95% CI: 0.31, 0.73), whereas those with high TMAO and high CMPF showed no association across adjusted models. CONCLUSIONS: High CMPF conferred an independent role in health benefits and might even counteract the unfavorable association between TMAO and outcomes. Whether higher circulating CMPF concentrations are due to fish consumption, and/or if CMPF is a protective factor, remains to be verified.

Nephropathic cystinosis in Poland: a 40-year retrospective study.

INTRODUCTION: Nephropathic cystinosis (NC) is a rare, autosomal recessive disorder leading to lysosomal accumulation of cystine. It is caused by mutations in the CTNS gene encoding a cystine cotransporter cystinosin. The infantile (INC) and juvenile (JNC) forms are distinguished. The former, responsible for 95% of cases, is characterized by development of renal Fanconi syndrome, end-stage kidney disease (ESKD), and extrarenal complications. A therapy with cysteamine significantly improves outcomes. There are limited data on NC in the Central Eastern European countries. OBJECTIVES: We aimed to evaluate the prevalence, genetic background, and clinical course of NC in the Polish population. PATIENTS AND METHODS: We performed a retrospective analysis of data of all identified NC patients in Poland. RESULTS: Between 1982 and 2017, 15 patients with NC (13 ICN, 2 JCN) were identified. The most common mutations of the CTNS gene were c.18_c.21delGACT and c.681+1G>A, whereas only 2 patients carried the 57 kb deletion. The majority (11/13) of INC patients with limited access to the cysteamine therapy developed ESKD at a median age of 11 years and 9 of them received kidney transplants. Three INC patients died at a median age of 24 years. In contrast, 2 INC patients treated adequately present normal kidney function and growth at the age of 13 and 11 years. Two JNC patients presented a milder course. CONCLUSIONS: The prevalence of NC in Poland is much lower than in the Western countries and its molecular background appears to be different. The unfavorable course in the majority of INC patients was caused by a limited access to the cysteamine treatment.

Associations between depressive symptoms and disease progression in older patients with chronic kidney disease: results of the EQUAL study.

Background: Depressive symptoms are associated with adverse clinical outcomes in patients with end-stage kidney disease; however, few small studies have examined this association in patients with earlier phases of chronic kidney disease (CKD). We studied associations between baseline depressive symptoms and clinical outcomes in older patients with advanced CKD and examined whether these associations differed depending on sex. Methods: CKD patients (≥65 years; estimated glomerular filtration rate ≤20 mL/min/1.73 m2) were included from a European multicentre prospective cohort between 2012 and 2019. Depressive symptoms were measured by the five-item Mental Health Inventory (cut-off ≤70; 0-100 scale). Cox proportional hazard analysis was used to study associations between depressive symptoms and time to dialysis initiation, all-cause mortality and these outcomes combined. A joint model was used to study the association between depressive symptoms and kidney function over time. Analyses were adjusted for potential baseline confounders. Results: Overall kidney function decline in 1326 patients was -0.12 mL/min/1.73 m2/month. A total of 515 patients showed depressive symptoms. No significant association was found between depressive symptoms and kidney function over time (P = 0.08). Unlike women, men with depressive symptoms had an increased mortality rate compared with those without symptoms [adjusted hazard ratio 1.41 (95% confidence interval 1.03-1.93)]. Depressive symptoms were not significantly associated with a higher hazard of dialysis initiation, or with the combined outcome (i.e. dialysis initiation and all-cause mortality). Conclusions: There was no significant association between depressive symptoms at baseline and decline in kidney function over time in older patients with advanced CKD. Depressive symptoms at baseline were associated with a higher mortality rate in men.

Patient-Reported Measures and Lifestyle Are Associated With Deterioration in Nutritional Status in CKD Stage 4-5: The EQUAL Cohort Study.

OBJECTIVE: The aim of this study was to explore the changes in nutritional status before dialysis initiation and to identify modifiable risk factors of nutritional status decline in older adults with advanced renal disease. DESIGN AND METHODS: The European Quality Study on treatment in advanced chronic kidney disease (EQUAL) is a prospective, observational cohort study involving six European countries. We included 1,103 adults >65 years with incident estimated glomerular filtration rate <20 mL/min/1.73 m2 not on dialysis, attending nephrology care. Nutritional status was assessed with the 7-point Subjective Global Assessment tool (7-p SGA), patient-reported outcomes with RAND-36 and the Dialysis Symptom Index. Logistic regression was used to estimate the associations between potential risk factors and SGA decline. RESULTS: The majority of the patients had a normal nutritional status at baseline, 28% were moderately malnourished (SGA ≤5). Overall, mean SGA decreased by -0.18 points/year, (95% confidence interval -0.21; -0.14). More than one-third of the study participants (34.9%) deteriorated in nutritional status (1 point decline in SGA) and 10.9% had a severe decline in SGA (≥2 points). The proportion of patients with low SGA (≤5) increased every 6 months. Those who dropped in SGA also declined in estimated glomerular filtration rate and mental health score. Every 10 points decrease in physical function score increased the odds of decline in SGA by 23%. Lower physical function score at baseline, gastrointestinal symptoms, and smoking were risk factors for impaired nutritional status. There was an interaction between diabetes and physical function on SGA decline. CONCLUSIONS: Nutritional status deteriorated in more than one-third of the study participants during the first year of follow-up. Lower patient-reported physical function, more gastrointestinal symptoms, and current smoking were associated with decline in nutritional status.

International prescribing patterns and polypharmacy in older people with advanced chronic kidney disease: results from the European Quality study.

BACKGROUND: People with chronic kidney disease (CKD) are at high risk of polypharmacy. However, no previous study has investigated international prescribing patterns in this group. This article aims to examine prescribing and polypharmacy patterns among older people with advanced CKD across the countries involved in the European Quality (EQUAL) study. METHODS: The EQUAL study is an international prospective cohort study of patients ≥65 years of age with advanced CKD. Baseline demographic, clinical and medication data were analysed and reported descriptively. Polypharmacy was defined as ≥5 medications and hyperpolypharmacy as ≥10. Univariable and multivariable linear regressions were used to determine associations between country and the number of prescribed medications. Univariable and multivariable logistic regression were used to determine associations between country and hyperpolypharmacy. RESULTS: Of the 1317 participants from five European countries, 91% were experiencing polypharmacy and 43% were experiencing hyperpolypharmacy. Cardiovascular medications were the most prescribed medications (mean 3.5 per person). There were international differences in prescribing, with significantly greater hyperpolypharmacy in Germany {odds ratio (OR) 2.75 [95% confidence interval (CI) 1.73-4.37]; P < 0.001, reference group UK}, the Netherlands [OR 1.91 (95% CI 1.32-2.76); P = 0.001] and Italy [OR 1.57 (95% CI 1.15-2.15); P = 0.004]. People in Poland experienced the least hyperpolypharmacy [OR 0.39 (95% CI 0.17-0.87); P = 0.021]. CONCLUSIONS: Hyperpolypharmacy is common among older people with advanced CKD, with significant international differences in the number of medications prescribed. Practice variation may represent a lack of consensus regarding appropriate prescribing for this high-risk group for whom pharmacological treatment has great potential for harm as well as benefit.

Uraemic symptom burden and clinical condition in women and men of ≥65 years of age with advanced chronic kidney disease: results from the EQUAL study.

BACKGROUND: The epidemiology and prognosis of chronic kidney disease (CKD) differ by sex. We aimed to compare symptom prevalence and the clinical state in women and men of ≥65 years of age with advanced CKD receiving routine nephrology care. METHODS: The European QUALity study on treatment in advanced chronic kidney disease (EQUAL) study follows patients from six European countries of ≥65 years of age years whose estimated glomerular filtration rate (eGFR) dropped to ≤20 mL/min/1.73 m2 for the first time during the last 6 months. The Dialysis Symptom Index was used to assess the prevalence and severity of 33 uraemic symptoms. Data on the clinical state at baseline were collected from medical records. Prevalence was standardized using the age distribution of women as the reference. RESULTS: The results in women (n = 512) and men (n = 967) did not differ with age (77.0 versus 75.7 years) or eGFR (19.0 versus 18.5). The median number of symptoms was 14 [interquartile range (IQR) 9-19] in women, and 11 (IQR 7-16) in men. Women most frequently reported fatigue {39% [95% confidence interval (CI) 34-45]} and bone/joint pain [37% (95% CI 32-42)] as severe symptoms, whereas more men reported difficulty in becoming sexually aroused [32% (95% CI 28-35)] and a decreased interest in sex [31% (95% CI 28-35)]. Anaemia [73% (95% CI 69-77) versus 85% (95% CI 82-87)] was less common in women than in men, as were smoking history and cardiovascular comorbidity. However, a diagnosis of liver disease other than cirrhosis, psychiatric disease and mild malnutrition were more common among women. CONCLUSIONS: Women in secondary care with an incident eGFR ≤20 mL/min/1.73 m2 reported a higher symptom burden, while their clinical state was considered similar or even more favourable as compared with men.

The use of different dialysis membranes in therapy of patients with multiple myeloma.

Free light chains accumulation is the reason of kidney injury in patients with multiple myeloma. The removal of free light chains can improve patients prognosis and survival, and in some cases allows for dialysotherapy discontinuation. Unfortunately, conventional dialysis is not effective enough in terms of free light chains removal. New high cut-off (HCO) techniques remove free light chains more effectively than conventional dialysis. In some cases, this technique may turn out better than hemodiafiltration. However, there are some differences between specific techniques in the removal of kappa and lambda light chains. Lambda light chains are better removed by polymethyl methacrylate membranes with a change of filter during dialysis. Kappa light chains are thoroughly removed by polymethyl methacrylate membranes and HCO (35,000 Da) polysulfone membranes. Unfortunately, it is very difficult to differentiate between the effect of HCO dialysis therapy and concomitant chemotherapy because some of the data is not fully conclusive. Using the proper technique for an individual patient may give optimally effective treatment results.

Dialysis-Related Parameters Influence Remodeling in the Venous Part of the Native Arteriovenous Fistula.

BACKGROUND: The aim of this study was to evaluate the association of hemodynamic parameters related to hemodialysis and antropometric parameters of patients with changes in the venous part of the arteriovenous fistula (AVF) at points of needling. METHODS: Two hundred forty-two hemodialysis (HD) patients (60.3% men), with median age 65 (interquartile range [IQR] 56-75) years, on HD treatment for a median of 49 (IQR 20-88) months with functioning fistula were recruited for the study. The history of vascular access, comorbidity, antropometric (body mass index, body surface area, and body composition), and dialysis-related parameters were analyzed. The cross-sectional area of upper extremity vessels were measured using ultrasound and included 2 points: A (arterial point for blood aspiration) and V (venous point for returning the blood after purification). The difference between A and V (A-V) was calculated. RESULTS: The median cross-sectional area of A was larger than V (1.04 [IQR 0.58-1.7] vs. 0.74 cm2 [IQR: 0.41-1.39], P <0.0001). The median difference between A and V (A-V) was 0.17 cm2 and positively correlated with mean blood flow (Qb), effective Kt/V, and time of AVF use. Other analyzed factors had no influence on A-V. In the multivariate analysis, the independent factor increasing the difference (A-V) was mean blood flow measured during HD sessions. CONCLUSIONS: The needling and utilization of AVF for hemodialysis may affect vein anatomy, namely causing dilatation at the arterial point and narrowing at venous point of AVF. We suggest that blood pump velocity of the dialysis machine may have an impact on these changes, but practical importance of these findings has to be elucidated. The significance of (A-V) factor in the prognosis of fistula complications should be further studied and confirmed in the prospective trials.

[Physical exercise in the rehabilitation of dialysis patients]. / Cwiczenia fizyczne w rehabilitacji chorych dializowanych.

A sedentary lifestyle is one of the main causes of low physical capacity and an independent risk factor for death in patients with end-stage renal disease (ESRD) undergoing hemodialysis (HD). The physical capacity of ESRD patients is 60% of an age-matched population with normal kidney function. Although muscular dysfunction is of crucial significance in low physical capacity, its etiology is more complex. The influence of uremic toxins, vitamin D3 deficiency, hyperparathyroidism, anemia, insulin resistance, androgen deficiency, mitochondrial dysfunction, malnutrition, inflammation, and cachexia are all taken into consideration. Physical rehabilitation improves physical proficiency, the performance of daily activities, and quality of life. In this review possible methods of rehabilitation and their advantages, disadvantages, and possible complications are presented.