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... Show moreRationale & 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 m(2).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. Show less
Rationale & Objective: Hypokalemia may accelerate kidney function decline. Both hypo- and hyperkalemia can cause sudden cardiac death. However, little is known about the relationship between... Show moreRationale & Objective: Hypokalemia may accelerate kidney function decline. Both hypo- and hyperkalemia can cause sudden cardiac death. However, little is known about the relationship between serum potassium and death or the occurrence of kidney failure requiring replacement therapy (KRT). We investigated this relationship in older people with chronic kidney disease (CKD) stage 4-5.Study Design: Prospective observational cohort study.Setting & Participants: We followed 1,714 patients (>= 65 years old) from the European Quality (EQUAL) study for 8 years from their first estimated glomerular filtration rate (eGFR) < 20 mL/min/1.73 m(2) measurement. Exposure: Serum potassium was measured every 3 to 6 months and categorized as <= 3.5, >3.5-<= 4.0, >4.0-<= 4.5, >4.5-<= 5.0 (reference), >5.0-<= 5.5, >5.5-<= 6.0, and >6.0 mmol/L.Outcome: The combined outcome death before KRT or start of KRT.Analytical Approach: The association between categorical and continuous time-varying potassium and death or KRT start was examined using Cox proportional hazards and restricted cubic spline analyses, adjusted for age, sex, diabetes, cardiovascular disease, renin-angiotensin-aldosterone system (RAAS) inhibition, eGFR, and subjective global assessment (SGA).Results: At baseline, 66% of participants were men, 42% had diabetes, 47% cardiovascular disease, and 54% used RAAS inhibitors. Their mean age was 76 +/- 7 (SD) years, mean eGFR was 17 +/- 5 (SD) mL/min/1.73 m(2), and mean SGA was 6.0 +/- 1.0 (SD). Over 8 years, 414 (24%) died before starting KRT, and 595 (35%) started KRT. Adjusted hazard ratios for death or KRT according to the potassium categories were 1.6 (95% CI, 1.1-2.3), 1.4 (95% CI, 1.1-1.7), 1.1 (95% CI, 1.0-1.4), 1 (reference), 1.1 (95% CI, 0.9-1.4), 1.8 (95% CI, 1.4-2.3), and 2.2 (95% CI, 1.5-3.3). Hazard ratios were lowest at a potassium of about 4.9 mmol/L.Limitations: Shorter intervals between potassium measurements would have allowed for more precise estimations.Conclusions: We observed a U-shaped relationship between serum potassium and death or KRT start among patients with incident CKD 4- 5, with a nadir risk at a potassium level of 4.9 mmol/L. These findings underscore the potential importance of preventing both high and low potassium in patients with CKD 4-5. Show less
Magagnoli, L.; Cozzolino, M.; Caskey, F.J.; Evans, M.; Torino, C.; Porto, G.; ... ; Jager, K.J. 2023
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... Show moreBackground 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 & GE;65 years with estimated glomerular filtration rate & LE;20 mL/min/1.73 m(2) 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. Show less
Chesnaye, N.C.; Caskey, F.J.; Dekker, F.W.; Rooi, E.N.M. de; Evans, M.; Heimburger, O.; ... ; Kuan, Y. 2023
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... Show moreBackground 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 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 similar to 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. Show less
Astley, M.; Caskey, F.J.; Evans, M.; Torino, C.; Szymczak, M.; Drechsler, C.; ... ; EQUAL Study Investigators 2023
Background. Patients with chronic kidney disease (CKD) are at a higher risk of major adverse cardiovascular events (MACE) compared with the general population, but gender differences in this risk,... Show moreBackground. Patients with chronic kidney disease (CKD) are at a higher risk of major adverse cardiovascular events (MACE) compared with the general population, but gender differences in this risk, especially in older adults, are not fully known. We aim to identify gender differences in the risk of MACE in older European CKD patients, and explore factors that may explain these differences.Methods. The European Quality study (EQUAL) is a prospective study on stage 4-5 CKD patients, >= 65 years old, not on dialysis, from Germany, Italy, the Netherlands, Poland, Sweden and the UK. Cox regression and cumulative incidence competing risk curves were used to identify gender differences in MACE risks. Mediation analysis was used to identify variables which may explain risk differences between men and women.Results. A total of 417 men out of 1134 (37%) and 185 women out of 602 women (31%) experienced at least one MACE, over a follow-up period of 5 years. Women had an 18% lower risk of first MACE compared with men (hazard ratio 0.82; 95% confidence interval 0.69-0.97; P =.02), which was attenuated after adjusting for pre-existing cardiometabolic comorbidities and cardiovascular risk factors. There were no significant gender differences in the risk of recurrent MACE or fatal MACE. The risk difference in MACE by gender was larger in patients aged 65-75 years, compared with patients over 75 years.Conclusions. In a cohort of older adults with advanced CKD, women had lower risks of MACE. These risk differences were partially explained by pre-existing cardiometabolic comorbidities and cardiovascular risk factors.[GRAPHICS]. Show less
Rooij, E.N.M. de; Meuleman, Y.; Fijter, J.W. de; Jager, K.J.; Chesnaye, N.C.; Evans, M.; ... ; EQUAL Study Investigators 2022
Background and objectives For older patients with kidney failure, lowering symptom burden may be more important than prolonging life. Dialysis initiation may affect individual kidney failure... Show moreBackground and objectives For older patients with kidney failure, lowering symptom burden may be more important than prolonging life. Dialysis initiation may affect individual kidney failure-related symptoms differently, but the change in symptoms before and after start of dialysis has not been studied. Therefore, we investigated the course of total and individual symptom number and burden before and after starting dialysis in older patients.Design, setting, participants, & measurements The European Quality (EQUAL) study is an ongoing, prospective, multicenter study in patients >= 65 years with an incident eGFR <= 20 ml/min per 1.73 m(2) . Using the dialysis symptom index (DSI), 30 symptoms were assessed every 3-6 months between 2012 and 2021. Scores for symptom number range from zero to 30 and, for burden, from zero to 150, with higher scores indicating more severity. Using mixed effects models, we studied symptoms during the year preceding and the year after dialysis initiation.Results We included 456 incident patients on dialysis who filled out at least one DSI during the year before or after dialysis. At dialysis initiation, mean (SD) participant age was 76 (6) years, 75% were men, mean (SD) eGFR was 8 (3) ml/min per 1.73 m(2), 44% had diabetes, and 46% had cardiovascular disease. In the year before dialysis initiation, symptom number increased +3.6 (95% confidence interval [95% CI], +2.5 to +4.6) and symptom burden increased +13.3 (95% CI, +9.5 to +17.0). In the year after, symptom number changed -0.9 (95% CI, -3.4 to +1.5) and burden decreased -5.9 (95% CI, -14.9 to -3.0). At dialysis initiation, "fatigue," "decreased interest in sex," and "difficulty becoming sexually aroused" had the highest prevalence of 81%, 69%, and 68%, respectively, with a burden of 2.7, 2.4, and 2.3, respectively. "Fatigue" somewhat improved after dialysis initiation, whereas the prevalence and burden of sexual symptoms further increased.Conclusions Symptom burden worsened considerably before and stabilized after dialysis initiation. "Fatigue," "decreased interest in sex," and "difficulty becoming sexually aroused" were considered most burdensome, of which only "fatigue" somewhat improved after dialysis initiation. Show less
Ramspek, C.L.; Boekee, R.; Evans, M.; Heimburger, O.; Snead, C.M.; Caskey, F.J.; ... ; EQUAL Study Investigators 2022
Introduction: Predicting the timing and occurrence of kidney replacement therapy (KRT), cardiovascular events, and death among patients with advanced chronic kidney disease (CKD) is clinically... Show moreIntroduction: Predicting the timing and occurrence of kidney replacement therapy (KRT), cardiovascular events, and death among patients with advanced chronic kidney disease (CKD) is clinically useful and relevant. We aimed to externally validate a recently developed CKD G4thorn risk calculator for these outcomes and to assess its potential clinical impact in guiding vascular access placement.Methods: We included 1517 patients from the European Quality (EQUAL) study, a European multicentre prospective cohort study of nephrology-referred advanced CKD patients aged $65 years. Model performance was assessed based on discrimination and calibration. Potential clinical utility for timing of referral for vascular access placement was studied with diagnostic measures and decision curve analysis (DCA).Results: The model showed a good discrimination for KRT and "death after KRT," with 2-year concordance (C) statistics of 0.74 and 0.76, respectively. Discrimination for cardiovascular events (2-year C-statistic: 0.70) and overall death (2-year C-statistic: 0.61) was poorer. Calibration was fairly accurate. Decision curves illustrated that using the model to guide vascular access referral would generally lead to less unused arteriovenous fistulas (AVFs) than following estimated glomerular filtration rate (eGFR) thresholds.Conclusion: This study shows moderate to good predictive performance of the model in an older cohort of nephrology-referred patients with advanced CKD. Using the model to guide referral for vascular access placement has potential in combating unnecessary vascular surgeries. Show less
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... Show moreBackground 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 m(2) 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. Show less
Background and objectives In older people with kidney failure, improving health-related quality of life is often more important than solely prolonging life. However, little is known about the... Show moreBackground and objectives In older people with kidney failure, improving health-related quality of life is often more important than solely prolonging life. However, little is known about the effect of dialysis initiation on health-related quality of life in older patients. Therefore, we investigated the evolution of health-related quality of life before and after starting dialysis in older patients with kidney failure. Design, setting, participants, & measurements The European Quality study is an ongoing prospective, multicenter study in patients aged >_65 years with an incident eGFR <_20 ml/min per 1.73 m2. Between April 2012 and December 2021, health-related quality of life was assessed every 3-6 months using the 36-item Short-Form Health Survey (SF-36), providing a mental component summary (MCS) and a physical component summary (PCS). Scores range from zero to 100, with higher scores indicating better health-related quality of life. With linear mixed models, we explored the course of health-related quality of life during the year preceding and following dialysis initiation. Results In total, 457 patients starting dialysis were included who filled out at least one SF-36 during follow-up. At dialysis initiation, mean +/- SD age was 76 +/- 6 years, eGFR was 8 +/- 3 ml/min per 1.73 m2, 75% were men, 9% smoked, 45% had diabetes, and 46% had cardiovascular disease. Median (interquartile range) MCS was 53 (38-73), and median PCS was 39 (27-58). During the year preceding dialysis, estimated mean change in MCS was -13 (95% confidence interval, -17 to -9), and in PCS, it was -11 (95% confidence interval, -15 to -7). In the year following dialysis, estimated mean change in MCS was +2 (95% confidence interval, -7 to +11), and in PCS, it was -2 (95% confidence interval, -11 to +7). Health-related quality-of-life patterns were similar for most mental (mental health, role emotional, social functioning, vitality) and physical domains (physical functioning, bodily pain, role physical). Conclusions Patients experienced a clinically relevant decline of both mental and physical health-related quality of life before dialysis initiation, which stabilized thereafter. These results may help inform older patients with kidney failure who decided to start dialysis. Show less
Windahl, K.; Irving, G.F.; Almquist, T.; Liden, M.K.; Stenvinkel, P.; Chesnaye, N.C.; ... ; EQUAL study invest Tora 2022
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... Show moreObjective: 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.& nbsp;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 m(2) 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.& nbsp;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.& nbsp;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. (C)& nbsp;2021 The Authors. Published by Elsevier Inc. on behalf of the National Kidney Foundation, Inc. Show less
Background Prospective cohort studies are challenging to deliver, with one of the main difficulties lying in retention of participants. The need to socially distance during the COVID-19 pandemic... Show moreBackground Prospective cohort studies are challenging to deliver, with one of the main difficulties lying in retention of participants. The need to socially distance during the COVID-19 pandemic has added to this challenge. The pre-COVID-19 adaptation of the European Quality (EQUAL) study in the UK to a remote form of follow-up for efficiency provides lessons for those who are considering changing their study design. Methods The EQUAL study is an international prospective cohort study of patients >= 65 years of age with advanced chronic kidney disease. Initially, patients were invited to complete a questionnaire (SF-36, Dialysis Symptom Index and Renal Treatment Satisfaction Questionnaire) at research clinics every 3-6 months, known as "traditional follow-up" (TFU). In 2018, all living patients were invited to switch to "efficient follow-up" (EFU), which used an abbreviated questionnaire consisting of SF-12 and Dialysis Symptom Index. These were administered centrally by post. Response rates were calculated using returned questionnaires as a proportion of surviving invitees, and error rates presented as the average percentage of unanswered questions or unclear answers, of total questions in returned questionnaires. Response and error rates were calculated 6-monthly in TFU to allow comparisons with EFU. Results Of the 504 patients initially recruited, 236 were still alive at the time of conversion to EFU; 111 of these (47%) consented to the change in follow-up. In those who consented, median TFU was 34 months, ranging from 0 to 42 months. Their response rates fell steadily from 88% (98/111) at month 0 of TFU, to 20% (3/15) at month 42. The response rate for the first EFU questionnaire was 60% (59/99) of those alive from TFU. With this improvement in response rates, the first EFU also lowered errors to baseline levels seen in early follow-up, after having almost trebled throughout traditional follow-up. Conclusions Overall, this study demonstrates that administration of shorter follow-up questionnaires by post rather than in person does not negatively impact patient response or error rates. These results may be reassuring for researchers who are trying to limit face-to-face contact with patients during the COVID-19 pandemic. Show less
Chesnaye, N.C.; Meuleman, Y.; Rooij, E.N.M. de; Hoogeveen, E.K.; Dekker, F.W.; Evans, M.; ... ; EQUAL Study Investigators 2022
Background and objectives The effect of sex on longitudinal health-related quality of life remains unknown in CKD. Here we assess differences in the sex-specific evolution of health-related quality... Show moreBackground and objectives The effect of sex on longitudinal health-related quality of life remains unknown in CKD. Here we assess differences in the sex-specific evolution of health-related quality of life in older men and women with advanced CKD.Design, setting, participants, & measurements The European Quality Study on Treatment in Advanced Chronic Kidney Disease is a European observational prospective cohort study in referred patients with CKD and an incident eGFR < 20 ml/min per 1.73 m(2) who are >= 65 years of age not on dialysis. Health-related quality of life was measured using the 36-Item Short Form Survey at 3- to 6-month intervals between April 2012 and September 2020, providing Physical Component Summary and Mental Component Summary scores. Trajectories were modeled by sex using linear mixed models, and sex differences in health-related quality-of-life slope were explored. Results We included 5345 health-related quality-of-life measurements in 1421 participants. At baseline, women had considerably lower mean Physical Component Summary (42) and Mental Component Summary (60) compared with men (Physical Component Summary: 55; Mental Component Summary: 69; P < 0.001). However, during follow-up, Physical Component Summary and Mental Component Summary scores declined approximately twice as fast in men (Physical Component Summary: 2.5 per year; 95% confidence interval, 1.8 to 3.1; Mental Component Summary: 2.7 per year; 95% confidence interval, 2.0 to 3.4) compared with in women (Physical Component Summary: 1.1 per year; 95% confidence interval, 0.1 to 2.0; Mental Component Summary: 1.6 per year; 95% confidence interval, 0.7 to 2.6). This difference was partly attenuated after adjusting for important covariates, notably eGFR decline. Higher serum phosphate, lower hemoglobin, and the presence of preexisting diabetes were associated with lower Physical Component Summary and Mental Component Summary scores in men but to a lesser extent in women. Conclusions Among older men and women with advanced CKD, women had lower health-related quality of life at baseline, but men experienced a more rapid decline in health-related quality of life over time. Show less
Chesnaye, N.C.; Dekker, F.W.; Evans, M.; Caskey, F.J.; Torino, C.; Postorino, M.; ... ; EQUAL Study Investigators 2021
Introduction. Understanding the mechanisms underlying the differences in renal decline between men and women may improve sex-specific clinical monitoring and management. To this end, we aimed to... Show moreIntroduction. Understanding the mechanisms underlying the differences in renal decline between men and women may improve sex-specific clinical monitoring and management. To this end, we aimed to compare the slope of renal function decline in older men and women in chronic kidney disease (CKD) Stages 4 and 5, taking into account informative censoring related to the sex-specific risks of mortality and dialysis initiation.Methods. The European QUALity Study on treatment in advanced CKD (EQUAL) study is an observational prospective cohort study in Stages 4 and 5 CKD patients >= 65years not on dialysis. Data on clinical and demographic patient characteristics were collected between April 2012 and December 2018. Estimated glomerular filtration rate (eGFR) was calculated using the CKD Epidemiology Collaboration equation. eGFR trajectory by sex was modelled using linear mixed models, and joint models were applied to deal with informative censoring.Results. We included 7801 eGFR measurements in 1682 patients over a total of 2911years of follow-up. Renal function declined by 14.0% [95% confidence interval (CI) 12.9-15.1%] on average each year. Renal function declined faster in men (16.2%/year, 95% CI 15.9-17.1%) compared with women (9.6%/year, 95% CI 6.3-12.1%), which remained largely unchanged after accounting for various mediators and for informative censoring due to mortality and dialysis initiation. Diabetes was identified as an important determinant of renal decline specifically in women.Conclusion. In conclusion, renal function declines faster in men compared with women, which remained similar after adjustment for mediators and despite a higher risk of informative censoring in men. We demonstrate a disproportional negative impact of diabetes specifically in women. Show less
Ramspek, C.L.; Evans, M.; Wanner, C.; Drechsler, C.; Chesnaye, N.C.; Szymczak, M.; ... ; EQUAL Study Investigators 2021
Background: Various prediction models have been developed to predict the risk of kidney failure in patients with CKD. However, guideline-recommended models have yet to be compared head to head,... Show moreBackground: Various prediction models have been developed to predict the risk of kidney failure in patients with CKD. However, guideline-recommended models have yet to be compared head to head, their validation in patients with advanced CKD is lacking, and most do not account for competing risks.Methods: To externally validate 11 existing models of kidney failure, taking the competing risk of death into account, we included patients with advanced CKD from two large cohorts: the European Quality Study (EQUAL), an ongoing European prospective, multicenter cohort study of older patients with advanced CKD, and the Swedish Renal Registry (SRR), an ongoing registry of nephrology-referred patients with CKD in Sweden. The outcome of the models was kidney failure (defined as RRT-treated ESKD). We assessed model performance with discrimination and calibration.Results: The study included 1580 patients from EQUAL and 13,489 patients from SRR. The average c statistic over the 11 validated models was 0.74 in EQUAL and 0.80 in SRR, compared with 0.89 in previous validations. Most models with longer prediction horizons overestimated the risk of kidney failure considerably. The 5-year Kidney Failure Risk Equation (KFRE) overpredicted risk by 10%-18%. The four- and eight-variable 2-year KFRE and the 4-year Grams model showed excellent calibration and good discrimination in both cohorts.Conclusions: Some existing models can accurately predict kidney failure in patients with advanced CKD. KFRE performed well for a shorter time frame (2 years), despite not accounting for competing events. Models predicting over a longer time frame (5 years) overestimated risk because of the competing risk of death. The Grams model, which accounts for the latter, is suitable for longer-term predictions (4 years). Show less
Background. Initiation of renal replacement therapy often results from a combination of kidney function deterioration and symptoms related to chronic kidney disease (CKD) progression. We... Show moreBackground. Initiation of renal replacement therapy often results from a combination of kidney function deterioration and symptoms related to chronic kidney disease (CKD) progression. We investigated the association between kidney function decline and symptom development in patients with advanced CKD.Methods. In the European Quality study on treatment in advanced CKD (EQUAL study), a European prospective cohort study, patients with advanced CKD aged >= 65 years and a kidney function that dropped <20 mL/min/1.73 m(2) were followed for 1 year. Linear mixed-effects models were used to assess the association between kidney function decline and symptom development. The sum score for symptom number ranged from 0 to 33 and for overall symptom severity from 0 to 165, using the Dialysis Symptom Index.Results. At least one kidney function estimate with symptom number or overall symptom severity was available for 1109 and 1019 patients, respectively. The mean (95% confidence interval) annual kidney function decline was 1.70 (1.32; 2.08) mL/min/1.73 m(2). The mean overall increase in symptom number and severity was 0.73 (0.28; 1.19) and 2.93 (1.34; 4.52) per year, respectively. A cross-sectional association between the level of kidney function and symptoms was lacking. Furthermore, kidney function at cohort entry was not associated with symptom development. However, each mL/min/1.73 m(2) of annual kidney function decline was associated with an extra annual increase of 0.23 (0.07; 0.39) in the number of symptoms and 0.87 (0.35; 1.40) in overall symptom severity.Conclusions. A faster kidney function decline was associated with a steeper increase in both symptom number and severity. Considering the modest association, our results seem to suggest that repeated thorough assessment of symptom development during outpatient clinic visits, in addition to the monitoring of kidney function decline, is important for clinical decision-making. Show less
Background Cohort studies are among the most robust of observational studies but have issues with external validity. This study assesses threats to external validity (generalizability) in the... Show moreBackground Cohort studies are among the most robust of observational studies but have issues with external validity. This study assesses threats to external validity (generalizability) in the European QUALity (EQUAL) study, a cohort study of people >65 years of age with Stage 4/5 chronic kidney disease. Methods Patients meeting the EQUAL inclusion criteria were identified in The Health Improvement Network database and stratified into those attending renal units, a secondary care cohort (SCC) and a not primary care cohort (PCC). Survival, progression to renal replacement therapy (RRT) and hospitalization were compared. Results The analysis included 250, 633 and 2464 patients in EQUAL, PCC and SCC. EQUAL had a higher proportion of men compared with PCC and SCC (60.0% versus 34.8% versus 51.4%). Increasing age >= 85 years {odds ratio [OR] 0.25 [95% confidence interval (CI) 0.15-0.40]} and comorbidity [Charlson Comorbidity Index >= 4, OR 0.69 (95% CI 0.52-0.91)] were associated with non-participation in EQUAL. EQUAL had a higher proportion of patients starting RRT at 1 year compared with SCC (8.1% versus 2.1%; P < 0.001). Patients in the PCC and SCC had increased risk of hospitalization [incidence rate ratio 1.76 (95% CI 1.27-2.47) and 2.13 (95% CI 1.59-2.86)] and mortality at 1 year [hazard ratio 3.48 (95% CI 2.1-5.7) and 1.7 (95% CI 1.1-2.7)] compared with EQUAL. Conclusions This study provides evidence of how participants in a cohort study can differ from the broader population of patients, which is essential when considering external validity and application to local practice. Show less
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... Show moreBackground. 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. Show less
Background-People with reduced glomerular filtration rate (GFR) often have elevated cardiac troponin T (cTnT) levels. It remains unclear how cTnT levels develop over time in those with chronic... Show moreBackground-People with reduced glomerular filtration rate (GFR) often have elevated cardiac troponin T (cTnT) levels. It remains unclear how cTnT levels develop over time in those with chronic kidney disease (CKD). The aim of this study was to prospectively study the association between cTnT and GFR over time in older advanced-stage CKD patients not on dialysis.Methods and Results-The EQUAL (European Quality Study) study is an observational prospective cohort study in stage 4 to 5 CKD patients aged >= 65 years not on dialysis (incident estimated GFR, <20 mL/min/1.73 m(2)). The EQUAL cohort used for the purpose of this study includes 171 patients followed in Sweden between April 2012 and December 2018. We used linear mixed models, adjusted for important groups of confounders, to investigate the effect of both measured GFR and estimated GFR on high-sensitivity cTnT (hs-cTnT) trajectory over 4 years. Almost all patients had at least 1 hs-cTnT measurement elevated above the 99th percentile of the general reference population (<= 14 ng/L). On average, hs-cTnT increased by 16%/year (95% CI, 13-19; P<0.0001). Each 15 mL/min/1.73 m(2) lower mean estimated GFR was associated with a 23% (95% CI, 14-31; P<0.0001) higher baseline hs-cTnT and 9% (95% CI, 5-13%; P<0.0001) steeper increase in hs-cTnT. The effect of estimated GFR on hs-cTnT trajectory was somewhat lower than a previous myocardial infarction (15%), but higher than presence of diabetes mellitus (4%) and male sex (5%).Conclusions-In CKD patients, hs-cTnT increases over time as renal function decreases. Lower CKD stage (each 15 mL/min/1.73 m2 lower) is independently associated with a steeper hs-cTnT increase over time in the same range as other established cardiovascular risk factors. Show less
Luijtgaarden, M.W.M. van de; Caskey, F.J.; Wanner, C.; Chesnaye, N.C.; Postorino, M.; Janmaat, C.J.; ... ; EQUAL Study Investigators 2019
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 >= 65years of age with... Show moreBackground 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 >= 65years 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 >= 65years of age years whose estimated glomerular filtration rate (eGFR) dropped to <= 20mL/min/1.73m(2) 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 75.7years) 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 <= 20mL/min/1.73m(2) reported a higher symptom burden, while their clinical state was considered similar or even more favourable as compared with men. Show less
Windahl, K.; Irving, G.F.; Almquist, T.; Liden, M.K.; Luijtgaarden, M. van de; Chesnaye, N.C.; ... ; Evans, M. 2018
