Background A potassium replete diet is associated with lower cardiovascular risk but may increase the risk of hyperkalemia, particularly in people using renin-angiotensin-aldosterone system... Show moreBackground A potassium replete diet is associated with lower cardiovascular risk but may increase the risk of hyperkalemia, particularly in people using renin-angiotensin-aldosterone system inhibitors. We investigated whether intracellular uptake and potassium excretion after an acute oral potassium load depend on the accompanying anion and/or aldosterone and whether this results in altered plasma potassium change.Methods In this placebo-controlled interventional cross-over trial including 18 healthy individuals, we studied the acute effects of one oral load of potassium citrate (40 mmol), potassium chloride (40 mmol), and placebo in random order after overnight fasting. Supplements were administered after a 6-week period with and without lisinopril pretreatment. Linear mixed effect models were used to compare blood and urine values before and after supplementation and between the interventions. Univariable linear regression was used to determine the association between baseline variables and change in blood and urine values after supplementation.Results During the 4-hour follow-up, the rise in plasma potassium was similar for all interventions. After potassium citrate, both red blood cell potassium-as measure of the intracellular potassium-and transtubular potassium gradient (TTKG)-reflecting potassium secretory capacity-were higher than after potassium chloride or potassium citrate with lisinopril pretreatment. Baseline aldosterone was significantly associated with TTKG after potassium citrate, but not after potassium chloride or potassium citrate with lisinopril pretreatment. The observed TTKG change after potassium citrate was significantly associated with urine pH change during this intervention (R50.60, P, 0.001).Conclusions With similar plasma potassium increase, red blood cell potassium uptake and kaliuresis were higher after an acute load of potassium citrate as compared with potassium chloride alone or pretreatment with lisinopril. Show less
Background Limited information exists regarding the safety of sodium-glucose cotransporter-2 inhibitors (SGLT2i) in patients with CKD treated in routine care. We evaluated the safety of SGLT2i in... Show moreBackground Limited information exists regarding the safety of sodium-glucose cotransporter-2 inhibitors (SGLT2i) in patients with CKD treated in routine care. We evaluated the safety of SGLT2i in patients with CKD and type 2 diabetes treated in US routine practice.Methods Using claims data from Medicare and two large US commercial databases (April 2013-December 2021), we included 96,128 adults with CKD stages 3-4 and type 2 diabetes who newly filled prescriptions for SGLT2i versus glucagon-like peptide-1 receptor agonists (GLP-1RA). Safety outcomes included diabetic ketoacidosis (DKA), lower limb amputations, nonvertebral fractures, genital infections, hypovolemia, AKI, hypoglycemia, and severe urinary tract infections (UTIs). Hazard ratios (HRs) and incidence rate differences per 1000 person-years were estimated after 1:1 propensity score matching, adjusted for >120 baseline characteristics.Results Compared with GLP-1RA, SGLT2i initiators had a higher risk of nonvertebral fractures (HR, 1.30 [95% confidence interval (CI), 1.03 to 1.65]; incidence rate difference, 2.13 [95% CI, 0.28 to 3.97]), lower limb amputations (HR, 1.65 [95% CI, 1.22 to 2.23]; incidence rate difference, 2.46 [95% CI, 1.00 to 3.92]), and genital infections (HR, 3.08 [95% CI, 2.73 to 3.48]; incidence rate difference, 41.26 [95% CI, 37.06 to 45.46]). Similar risks of DKA (HR, 1.07 [95% CI, 0.74 to 1.54]; incidence rate difference, 0.29 [95% CI, -0.89 to 1.46]), hypovolemia (HR, 0.99 [95% CI, 0.86 to 1.14]; incidence rate difference, 0.20 [95% CI, -2.85 to 3.25]), hypoglycemia (HR, 1.08 [95% CI, 0.92 to 1.26]; incidence rate difference, 1.46 [95% CI, -1.31 to 4.23]), and severe UTI (HR, 1.02 [95% CI, 0.87 to 1.19]; incidence rate difference, 0.35 [95% CI, -2.51 to 3.21]) were observed. SGLT2i had lower risk for AKI (HR, 0.93 [95% CI, 0.87 to 0.99]; incidence rate difference, -6.75 [95% CI, -13.69 to 0.20]).Conclusions In US patients with CKD and type 2 diabetes receiving routine care, SGLT2i use was associated with higher risks of genital infections and potentially lower limb amputations and nonvertebral fractures. 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
Background and objectives In the BLISS-LN study, belimumab improved kidney outcomes in adult patients with active lupus nephritis. This 28-week open-label extension of BLISS-LN assessed belimumab's... Show moreBackground and objectives In the BLISS-LN study, belimumab improved kidney outcomes in adult patients with active lupus nephritis. This 28-week open-label extension of BLISS-LN assessed belimumab's safety and efficacy. Design, setting, participants, & measurements Eligible patients completing BLISS-LN received monthly intravenous belimumab 10 mg/kg plus standard therapy. End points included safety, open-label week 28 primary efficacy renal response (urine protein-creatinine ratio [UPCR] <_0.7, eGFR no more than 20% below open-label baseline value or >_60 ml/min per 1.73 m2, no prohibited medications) and complete renal response (UPCR < 0.5, eGFR no more than 10% below open-label baseline value or >_90 ml/min per 1.73 m2, no prohibited medications), and UPCR and eGFR by visit. Responses were also analyzed post hoc using the double-blind phase criteria. Results Of 257 enrolled patients, 255 were treated (safety population: n=123 switched from placebo-tobelimumab; n=132 remained on belimumab); 245 (97%) patients completed the study. Adverse events and serious adverse events were experienced by 62% and 4% of placebo-to-belimumab patients, respectively, and by 70% and 8% of belimumab-to-belimumab patients, respectively. One death occurred in the placebo-to-belimumab group. From open-label baseline to week 28, increases occurred in the proportions of patients achieving primary efficacy renal response (placebo-to-belimumab: from 60% to 67%; belimumab-to-belimumab: from 70% to 75%) and complete renal response (placebo-to-belimumab: from 36% to 48%; belimumab-to-belimumab: from 48% to 62%). Based on double-blind phase criteria, changes also occurred in the proportions achieving primary efficacy renal response (placebo-to-belimumab: from 54% to 53%; belimumab-to-belimumab: from 66% to 52%) and complete renal response (placebo-to-belimumab: from 34% to 35%; belimumab-to-belimumab: from 46% to 41%). The seeming decrease in response rates in the belimumab-to-belimumab groups was attributed to discontinuations/administration of glucocorticoids for non-SLE reasons as opposed to nephritis. Median UPCR and eGFR values were similar at open-label baseline and week 28. Conclusions No new safety signals were identified, and efficacy was generally maintained throughout the open label phase. contributing the affiliations listed at the article. Correspondence: Dr. Richard Division of Rheumatology, Northwell Donald and Zucker School Medicine, Northwell Suite 302, NY 11021. RFurie@northwell.edu 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
Background and objectives: C3 glomerulopathy and idiopathic Ig-associated membranoproliferative GN are kidney diseases characterized by abnormal glomerular complement C3 deposition. These... Show moreBackground and objectives: C3 glomerulopathy and idiopathic Ig-associated membranoproliferative GN are kidney diseases characterized by abnormal glomerular complement C3 deposition. These conditions are heterogeneous in outcome, but approximately 50% of patients develop kidney failure within 10 years. Design, setting, participants, & measurements: To improve identification of patients with poor prognosis, we performed a detailed analysis of percutaneous kidney biopsies in a large cohort of patients. Using a validated histologic scoring system, we analyzed 156 native diagnostic kidney biopsies from a retrospective cohort of 123patients with C3 glomerulopathy and 33 patients with Ig-associated membranoproliferative GN. We used linear regression, survival analysis, and Cox proportional hazards models to assess the relationship between histologic and clinical parameters with outcome. Results: Frequent biopsy features were mesangial expansion and hypercellularity, glomerular basement membrane double contours, and endocapillary hypercellularity. Multivariable analysis showed negative associations between eGFR and crescents, interstitial inflammation, and interstitialfibrosis/tubular atrophy. Proteinuria positively associated with endocapillary hypercellularity and glomerular basement membrane double contours. Analysis of second native biopsies did not demonstrate associations between immunosuppression treatment and improvement in histology. Using a composite outcome, risk of progression to kidney failure associated with eGFR and proteinuria at the time of biopsy, cellular/fibrocellular crescents, segmental sclerosis, and interstitial fibrosis/tubular atrophy scores. Conclusions: Our detailed assessment of kidney biopsy data indicated that cellular/fibrocellular crescents and interstitial fibrosis/tubular atrophy scores were significant determinants of deterioration in kidney function. Show less
Kramers, B.J.; Koorevaar, I.W.; Gastel, M.D.A. van; Goor, H. van; Hallows, K.R.; Heerspink, H.L.; ... ; Meijer, E. 2022
Background and objectives: The vasopressin V2 receptor antagonist tolvaptan is the only drug that has been proven to be nephroprotective in autosomal dominant polycystic kidney disease (ADPKD).... Show moreBackground and objectives: The vasopressin V2 receptor antagonist tolvaptan is the only drug that has been proven to be nephroprotective in autosomal dominant polycystic kidney disease (ADPKD). Tolvaptan also causes polyuria, limiting tolerability. We hypothesized that cotreatment with hydrochlorothiazide or metformin may ameliorate this side effect. Design, setting, participants, & measurements: We performed a clinical study and an animal study. In a randomized, controlled, double-blind, crossover trial, we included 13 tolvaptan-treated patients with ADPKD. Patients were treated for three 2-week periods with hydrochlorothiazide, metformin, or placebo in random order. Primary outcome was change in 24-hour urine volume. We also measured GFR and a range of metabolic and kidney injury markers. Results: Patients (age 45 +/- 8 years, 54% women, measured GFR of 55 +/- 11 ml/min per 1.73 m(2)) had a baseline urine volume on tolvaptan of 6.9 +/- 1.4 L/24 h. Urine volume decreased to 5.1 L/24 h (P<0.001) with hydrochlorothiazide and to 5.4 L/24 h (P<0.001) on metformin. During hydrochlorothiazide treatment, plasma copeptin (surrogate for vasopressin) decreased, quality of life improved, and several markers of kidney damage and glucose metabolism improved. Metformin did not induce changes in these markers or in quality of life. Given these results, the effect of adding hydrochlorothiazide to tolvaptan was investigated on long-term kidney outcome in an animal experiment. Water intake in tolvaptan-hydrochlorothiazide cotreated mice was 35% lower than in mice treated with tolvaptan only. Combination treatment was superior to "no treatment" on markers of disease progression (kidney weight, P =0.003 and cystic index, P =0.04) and superior or equal to tolvaptan alone. Conclusions: Both metformin and hydrochlorothiazide reduced tolvaptan-caused polyuria in a short-term study. Hydrochlorothiazide also reduced polyuria in a long-term animal model without negatively affecting nephroprotection. Show less
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
Background and objectives Predictingdiseaseprogression in patientswith autosomaldominantpolycystic kidney disease (ADPKD) poses a challenge, especially in early- stage disease when kidney function... Show moreBackground and objectives Predictingdiseaseprogression in patientswith autosomaldominantpolycystic kidney disease (ADPKD) poses a challenge, especially in early- stage disease when kidney function is not yet affected. Ongoing growth of cysts causes maximal urine-concentrating capacity to decrease from early on. We therefore hypothesized that the urine-to-plasmaurea ratio, as a reflection of the urine-concentrating capacity, can be used as a marker to predict ADPKD progression. Design The urine- to-plasma urea ratio was calculated by dividing concentrations of early morning fasting spot urine urea by plasma urea. First, this ratio was validated as surrogate marker in 30 patients with ADPKD who underwent a prolongedwater deprivation test. Thereafter, associationwith kidney outcomewas evaluated in 583 patients with ADPKDwith a broad range of kidney function. Multivariable mixed-model regressionwas used to assess association with eGFR slope, and logarithmic regression to identify patients with rapidly progressive disease, using a cutoff of 23.0 ml/min per 1.73 m2 per year. The urine-to-plasma urea ratio was compared with established predictors, namely, sex, age, baseline eGFR, Mayo Clinic height-adjusted total kidney volume class, and PKD gene mutation. Results The maximal urine-concentrating capacity and urine-to-plasma urea ratio correlated strongly (R50.90; P,0.001). Next, the urine-to-plasma urea ratio was significantly associated with rate of eGFR decline during a median follow-up of 4.0 (interquartile range, 2.6-5.0) years, both crude and after correction for established predictors (b50.58; P50.02). The odds ratio of rapidly progressive diseasewas 1.35 (95% confidence interval, 1.19 to 1.52; P,0.001) for every 10 units decrease in urine-to-plasma urea ratio, with adjustment for predictors. A combined risk score of the urine-to-plasma urea ratio, MayoClinic height-adjusted total kidney volume class, and PKD mutation predicted rapidly progressive disease better than each of the predictors separately. Conclusions The urine-to-plasma urea ratio, which is calculated fromroutine laboratory measurements, predicts disease progression in ADPKD in addition to other risk markers. Show less
Background and objectives The histopathologic classification for ANCA-associated GN distinguishes four classes on the basis of patterns of injury. In the original validation study, these classes... Show moreBackground and objectives The histopathologic classification for ANCA-associated GN distinguishes four classes on the basis of patterns of injury. In the original validation study, these classes were ordered by severity of kidney function loss as follows: focal, crescentic, mixed, and sclerotic. Subsequent validation studies disagreed on outcomes in the crescentic and mixed classes. This study, driven by the original investigators, provides several analyses in order to determine the current position of the histopathologic classification of ANCA-associated GN.Design, setting, participants, & measurements Avalidation study was performed with newly collected data from 145 patients from ten centers worldwide, including an analysis of interobserver agreement on the histopathologic evaluation of the kidney biopsies. This study also included a meta-analysis on previous validation studies and a validation of the recently proposed ANCA kidney risk score.Results The validation study showed that kidney failure at 10-year follow-up was significantly different between the histopathologic classes (P < 0.001). Kidney failure at 10-year follow-up was 14% in the crescentic class versus 20% in the mixed class (P=0.98). In themeta-analysis, no significant difference in kidney failure was also observed when crescentic class was compared with mixed class (relative risk, 1.15; 95% confidence interval, 0.94 to 1.41). When we applied the ANCA kidney risk score to our cohort, kidney survival at 3 years was 100%, 96%, and 77% in the low-, medium-, andhigh-risk groups, respectively (P<0.001). These survival percentages are higher compared with the percentages in the original study.Conclusions The crescentic and mixed classes seem to have a similar prognosis, also after adjusting for differences in patient populations, treatment, and interobserver agreement. However, at this stage, we are not inclined to merge the crescentic and mixed classes because the reported confidence intervals do not exclude important differences in prognosis and because an important histopathologic distinction would be lost. Show less
Fu, E.L.; Trevisan, M.; Clase, C.M.; Evans, M.; Lindholm, B.; Rotmans, J.I.; ... ; Carrero, J.J. 2019
Background and objectives Data from observational and interventional studies provide discordant results regarding the relationship between creatinine increase after renin-angiotensin system... Show moreBackground and objectives Data from observational and interventional studies provide discordant results regarding the relationship between creatinine increase after renin-angiotensin system inhibition (RASi) and adverse outcomes. We compared health outcomes among patients with different categories of increase in creatinine upon initiation of RASi in a large population-based cohort.Design, setting, participants, & measurements We performed a retrospective analysis of the Stockholm CREAtinine Measurements database, which contains complete information on diagnoses, medication dispensation claims, and laboratory test results for all Stockholm citizens accessing health care. Included were 31,951 adults initiating RASi during 2007-2011 with available pre- and postinitiation creatinine monitoring. Multivariable Cox regression was used to compare mortality, cardiovascular and ESKD events among individuals with different ranges of creatinine increases within 2 months after starting treatment.Results In a median follow-up of 3.5 years, acute increases in creatinine were associated with mortality (3202 events) in a graded manner: compared with creatinine increases <10%, a 10%-19% increase showed an adjusted hazard ratio (HR) of 1.15 (95% confidence interval [95% CI], 1.05 to 1.27); HR 1.22 (95% CI, 1.07 to 1.40) for 20%-29%; HR 1.55 (95% CI, 1.36 to 1.77) for >= 30%. Similar graded associations were present for heart failure (2275 events, P<0.001) and ESKD (52 events; P<0.001), and, less consistently, myocardial infarction (842 events, P=0.25). Results were robust across subgroups, among continuing users, when patients with decreases in creatinine were excluded from the reference group, and after accounting for death as a competing risk.Conclusions Among real-world monitored adults, increases in creatinine (>10%) after initiation of RASi are associated with worse health outcomes. These results do not address the issue of discontinuation of RASi when plasma creatinine increases but do suggest that patients with increases in creatinine have higher subsequent risk of cardiovascular and kidney outcomes. Show less
