Greater Chronic Kidney Disease Research Articles

A quantitative assessment of renal function utilizing albuminuria in pediatric heart transplant recipients.

Kidney disease is common after pediatric heart transplantation. Serum creatinine-based glomerular filtration rate is the most frequently reported measure of kidney function. Albuminuria is an additional marker of kidney dysfunction and is not well described in this population. In this study, we evaluate the prevalence and degree of albuminuria and describe clinical factors associated with albuminuria in a cohort of pediatric heart transplant recipients. This was a cross-sectional study of pediatric heart transplant recipients. Albuminuria was assessed using spot urine albumin-to-creatinine ratio collected at the most recent annual screening cardiac catheterization through August 2019. In 115 patients at a median duration of 10.2 years post-transplant, 39% had albuminuria. Stage 3 or greater chronic kidney disease was present in 6%. The immunosuppressive regimen at the time of measurement contained a calcineurin inhibitor (CNI) in 88% and a proliferation signal inhibitor (PSI) in 62%. In multivariable modeling, lower eGFR, PSI use, and younger age at transplant were associated with higher levels of albuminuria, whereas CNI use was associated with lower levels of albuminuria. Albuminuria is a prevalent finding in medium-term follow up of pediatric heart transplant recipients, reflecting kidney injury, and is associated with other markers of kidney dysfunction, such as low eGFR. Younger age at transplant, lower eGFR, and PSI use were among the associations with albuminuria.

Pulmonary Artery Pressure-Guided Heart Failure Management Reduces Hospitalizations in Patients With Chronic Kidney Disease.

Hemodynamic-guided heart failure management is a superior strategy to prevent decompensation leading to hospitalization compared with traditional clinical methods. It remains unstudied if hemodynamic-guided care is effective across severities of comorbid renal insufficiency or if this strategy impacts renal function over time. In the CardioMEMS US PAS (Post-Approval Study), heart failure hospitalizations were compared from 1 year before and after pulmonary artery sensor implantation in 1200 patients with New York Heart Association class III symptoms and a previous hospitalization. Hospitalization rates were evaluated in all patients grouped into baseline estimated glomerular filtration rate (eGFR) quartiles. Chronic kidney disease progression was evaluated in patients with renal function follow-up data (n=911). Patients with stage 2 or greater chronic kidney disease at baseline exceeded 80%. Heart failure hospitalization risk was lower in all eGFR quartiles ranging from a hazard ratio of 0.35 (0.27-0.46; P<0.0001) in patients with eGFR >65 mL/min per 1.73 m2 to 0.53 (0.45-0.62; P<0.0001) in patients with eGFR ≤37 mL/min per 1.73 m2. Renal function was preserved or improved in most patients. Survival was different between quartiles and lower in quartiles with more advanced chronic kidney disease. Hemodynamic-guided heart failure management using remotely obtained pulmonary artery pressures is associated with lower hospitalization rates and general preservation of renal function in all eGFR quartiles or chronic kidney disease stages.

In the Limelight: December 2022

In the Limelight: December 2022

Abstract P186: Obstructive Sleep Apnea and Risk of Chronic Kidney Disease in the ARIC Sleep Heart Health Study

Background: Obstructive sleep apnea (OSA) is a prevalent sleep disorder and may be associated with the development of chronic kidney disease (CKD) through hypoxia, inflammation, and oxidative stress. However, the prospective relationship between OSA and incident CKD remains unknown. In this study, we leveraged in-home polysomnography (PSG) data from a large community-based cohort of adults to examine the association between OSA and risk of incident CKD in late-midlife. Methods: Participants in the Atherosclerosis Risk in Communities (ARIC) study (N=1,525; mean age=62.5 ± 5.4 years, 52.4% female) completed in-home PSG assessments as part of the Sleep Heart Health Study. OSA severity was defined according to apnea-hypopnea index (AHI) (events/hour): normal &lt;5.0, mild 5.0-14.9, moderate 15.0-29.9, and severe ≥30.0. Incident CKD was defined according to estimated glomerular filtration rate (eGFR) &lt;60 mL/min/1.73 m 2 and at least 25% decline in eGFR from baseline, CKD-related hospitalization or death, or end-stage renal disease. Cox proportional hazards regression was used to estimate OSA severity with risk of incident CKD. Models were adjusted for demographics, health behaviors, BMI, and other markers of cardiometabolic conditions. Results: Among 1,525 participants, a total of 461 CKD events occurred over an average of 19 years of follow-up. After adjustment for demographics and health behaviors, severe OSA (AHI ≥30.0) was associated with increased risk of CKD (Hazard Ratio (HR): 1.51; 95% Confidence Interval (CI): 1.08, 2.10). This association was attenuated after additional adjustment for BMI (HR; 1.07, CI: 0.75, 1.52). Conclusions: Overall, OSA was linked to greater CKD risk. The association was attenuated after adjusting for obesity, a risk factor for both conditions. Due the high prevalence of OSA and CKD in the US adult population, more investigation is needed. Figure 1. Estimated probability of years free of Chronic Kidney Disease (CKD) by obstructive sleep apnea (OSA) severity in the ARIC Sleep Heart Health Study:

Diabetes mellitus is the only independent predictor of both postoperative and long term renal functions in elective laparoscopic partial nephrectomy with limited or overextended warm ischemia.

To investigate the predictive factors of renal functional change at postoperative period and at last follow-up in patients undergoing elective and clamped laparoscopic partial nephrectomy (LPN) with limited (≤20 minutes) and overextended (≥40 minutes) warm ischemia time (WIT). From our prospectively collected LPN database, elective and warm ischemia-applied LPNs were retrospectively analyzed in two groups: limited (n=55, Group 1, WIT≤20 minutes) and overextended (n=28, Group 2, WIT≥40 minutes) WITs. Preoperatively, estimated glomerular filtration rate (eGFR) was ≥60 mL/min/1.73 m2 in all patients. Demographic, clinical, perioperative and renal functional parameters were compared between two groups. Age, diabetes mellitus (DM), pathological tumor size, preoperative eGFR and WIT were used in multivariable analyses to investigate the independent predictors of de novo Stage 3 or greater chronic kidney disease (CKD) (eGFR<60 mL/min/1.73m2) at postoperative period and at the last follow-up. Preoperative (p=0.009) and pathological (p=0.011) tumor size, PADUA (p=0.001) and R.E.N.A.L. Nephrometry (p=0.006) scores and operative time (p<0.001) were significantly higher in Group 2. Preoperative eGFR (86 vs. 88 mL/min/1.73 m2, p=0.328) was similar between two groups. In postoperative period, compared to Group 1, decreased eGFR (86 vs. 62.5 mL/min/1.73 m2, p<0.001) and percent preserved eGFR (97.2 vs. 77.2%, p<0.001) were found in Group 2. After median follow-up of 33 and 30 months (p=0.732) for Groups 1 and 2, respectively, eGFR at the last follow-up (84 vs. 80.0 mL/min/1.73 m2, p=0.347) and percentage preserved eGFR at last follow-up (97.7 vs. 92.5%, p=0.806) were similar between two groups. Overextended WIT (≥40 minutes), preoperative decreased eGFR (<77.5 mL/min/1.73m2) and DM were the independent predictors of de novo Stage 3 or greater CKD at postoperative period, while DM and age were the predictors of de novo Stage 3 or greater CKD at the last follow-up. Overextended WIT (≥40 minutes) caused significant postoperative renal functional loss in elective LPN but this functional loss recovers at long term follow-up. However, diabetes mellitus is the only predictor of renal functional loss both in the postoperative period and at the last follow-up.

Risk Factors for Kidney Disease in Hb SC and Hb Sβ+-Thalassemia Sickle Cell Disease

Sickle cells disease (SCD) is an inherited red blood disorder that leads to acute and chronic organ complications. The kidneys are among the most commonly affected organ systems and chronic kidney disease (CKD) predicts increased morbidity and early mortality in SCD (PMID 1892333). Risk factors for CKD have been primarily investigated in patients with homozygous inheritance of the hemoglobin (Hb) S mutation but are not as well understood in other SCD variants, such as in those with Hb SC or Hb SB+-thalassemia. We investigated clinical, laboratory, and genetic predictors (α-thalassemia and the APOL1 G1 and G2 kidney disease risk variants) for CKD in a combined analysis of non-Hb SS patients from the University of Illinois at Chicago and the multi-center Walk-PHaSST cohort. Clinical and laboratory variables were obtained at the time of enrolment. Estimated glomerular filtration (eGFR) rate was calculated using the CKD-EPI formula and CKD stage was defined according to the KDIGO guidelines. Univariate analysis for the association of variables with eGFR, albuminuria, and CKD stage were conducted using the linear trend test and Cochran's test for linear trend. Variables with a P &lt; 0.1 were entered into linear and ordinal logistic regression models adjusting for age and sex. Median and interquartile ranges (IQR) are provided. Two hundred and forty-seven patients were included in this analysis. The median age of this cohort was 39 years (IQR, 24 - 50 years), 62% were female, 16% were on hydroxyurea, and 72% were Hb SC genotype. Albuminuria data was available in 174 patients; microalbuminuria (albuminuria 30 - 300 mg/g creatinine) was present in 24% and macroalbuminuria (albuminuria &gt; 300 mg/g creatinine) in 5% of patients. Patients with higher urine albumin concentration were older, had higher systolic blood pressures and LDH concentrations, and lower hemoglobin concentrations (P ≤ 0.03). On multivariate analysis, the urine albumin concentration was independently associated with a higher systolic blood pressure (log transformed β +3.08 ± 1.09; P = 0.005) and a lower hemoglobin concentration (β -0.17 ± 0.09; P = 0.05). Patients with lower eGFR were older, had higher body mass indexes and systolic blood pressures, lower hemoglobin concentrations, and were more frequently female (P ≤ 0.04). No variables were independently associated with eGFR on multivariate analysis after adjusting for age and sex. When applying the KDIGO CKD staging criteria, 67% were classified as not having CKD (urine albumin &lt; 30mg/g creatinine and eGFR &gt; 60 mL/min/1.73m2), 23% had stage 1 or 2 CKD (urine albumin ≥ 30mg/g creatinine and eGFR &gt; 60 mL/min/1.73m2), and 10% had stage 3 or greater CKD (eGFR &lt; 60 mL/min/1.73m2). Patients with increasing CKD stage were older, had higher systolic blood pressures and LDH concentrations, and lower hemoglobin concentrations (Table 1) (P ≤ 0.005). On multivariate analysis, incremental CKD stage was independently associated with lower hemoglobin (OR 0.91, 95%CI: 0.88 - 0.94; P = 0.002) and higher LDH (natural log OR 1.43, 95% CI: 1.27 - 1.61; P = 0.004) concentrations. We did not observe an association between coinheritance of α-thalassemia or the APOL1 G1/G2 risk variants with urine albumin concentration, eGFR, or CKD stage. In conclusion, we demonstrate that CKD is a common comorbidity that is observed in approximately one third of SCD patients with the Hb SC or Hb Sβ+-thalassemia genotypes. A lower hemoglobin concentration and higher systolic blood pressure were independently associated with greater urine albumin concentration. This may reflect anemia causing reduced oxygen delivery to the renal cortex and hypertension-mediated vascular and glomerular damage. The association of worsening CKD stage with lower hemoglobin and higher LDH concentrations, consistent with increased hemolysis, is similar to what has been observed in the Hb SS genotypes. The potential effects of hemolysis on kidney function in the Hb SC and Sβ+-thalassemia genotypes will need to be explored further. Disclosures Gladwin: Bayer Pharmaceuticals: Other: Co-investigator; United Therapeutics: Patents &amp; Royalties: Co-inventor on an NIH government patent for the use of nitrite salts in cardiovascular diseases ; Globin Solutions, Inc: Patents &amp; Royalties: Provisional patents for the use of recombinant neuroglobin and heme-based molecules as antidotes for CO poisoning. Gordeuk:Novartis: Consultancy, Honoraria, Research Funding; Global Blood Therapeutics: Consultancy, Honoraria, Research Funding; Emmaus: Consultancy, Honoraria; Modus Therapeutics: Consultancy, Honoraria; Novartis: Consultancy, Honoraria, Research Funding; Pfizer: Research Funding; Modus Therapeutics: Consultancy, Honoraria; Pfizer: Research Funding; Inctye: Research Funding; Inctye: Research Funding; CSL Behring: Consultancy, Honoraria, Research Funding; CSL Behring: Consultancy, Honoraria, Research Funding; Ironwood: Research Funding; Ironwood: Research Funding; Imara: Research Funding; Imara: Research Funding. Saraf:Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees; Pfizer: Research Funding.

Chronic prolonged hyponatremia and risk of hip fracture in elderly patients with chronic kidney disease.

Chronic prolonged hyponatremia (CPH) is a risk factor for hip fracture in the general population. Whether CPH increases hip fracture risk in chronic kidney disease (CKD) patients is unknown. Case-control study in patients over 60 years of age with stage 3 or greater CKD. Patients who had a hip fracture were referred to as cases (n = 1236) and controls had no hip fracture (n = 4515). Patients were classified as having CPH if serum sodium was <135 mEq/L on at least two occasions separated by a minimum of 90 days prior to the diagnosis of hip fracture (cases) or at any time during the study period (controls). Conditional logistic regression models were used to test the association between CPH and hip fracture. Analyses were conducted for patients with and without osteoporosis and falls and for patients with age >70 years versus ≤70 years. CPH was present in 21% of cases and 10% of controls (p < 0.001; sodium level: 131-134 mEq/L). In univariate logistic regression analysis, CPH was associated with higher odds of hip fracture (odds ratio [OR] 2.44, (95% [CI] 2.07-2.89). In a multivariate model adjusted for comorbidities, medications and laboratory parameters CPH association with higher odds of Hip fracture was attenuated but remained significant (OR 1.36, 95% CI 1.04-1.78). The association between CPH and risk of hip fracture was consistent in patients with or without osteoporosis and falls and across the age strata. Chronic prolonged hyponatremia is a risk factor for hip fracture in CKD patients older than 60 years of age.

Use of Peripherally Inserted Central Catheters in Patients With Advanced Chronic Kidney Disease: A Prospective Cohort Study.

Existing guidelines, including Choosing Wisely recommendations, endorse avoiding placement of peripherally inserted central catheters (PICCs) in patients with chronic kidney disease (CKD). To describe the frequency of and characteristics associated with PICC use in hospitalized patients with stage 3b or greater CKD (glomerular filtration rate [GFR] <45 mL/min/1.73 m2). Prospective cohort study. 52 hospitals participating in the Michigan Hospital Medicine Safety Consortium. Hospitalized medical patients who received a PICC between November 2013 and September 2016. Percentage of patients receiving PICCs who had CKD, frequency of PICC-related complications, and variation in the proportion of PICCs placed in patients with CKD. Of 20545 patients who had PICCs placed, 4743 (23.1% [95% CI, 20.9% to 25.3%]) had an estimated GFR (eGFR) less than 45 mL/min/1.73 m2 and 699 (3.4%) were receiving hemodialysis. In the intensive care unit (ICU), 30.9% (CI, 29.7% to 32.2%) of patients receiving PICCs had an eGFR less than 45 mL/min/1.73 m2; the corresponding percentage in wards was 19.3% (CI, 18.8% to 19.9%). Among patients with an eGFR less than 45 mL/min/1.73 m2, multilumen PICCs were placed more frequently than single-lumen PICCs. In wards, PICC-related complications occurred in 15.3% of patients with an eGFR less than 45 mL/min/1.73 m2 and in 15.2% of those with an eGFR of 45 mL/min/1.73 m2 or higher. The corresponding percentages in ICU settings were 22.4% and 23.9%. In patients with an eGFR less than 45 mL/min/1.73 m2, PICC placement varied widely across hospitals (interquartile range, 23.7% to 37.8% in ICUs and 12.8% to 23.7% in wards). Nephrologist approval for placement could not be determined, and 2.7% of eGFR values were unknown and excluded. In this sample of hospitalized patients who received PICCs, placement in those with CKD was common and not concordant with clinical guidelines. Blue Cross Blue Shield of Michigan and Blue Care Network.

Development and Validation of a Deep-Learning Model to Screen for Hyperkalemia From the Electrocardiogram

For patients with chronic kidney disease (CKD), hyperkalemia is common, associated with fatal arrhythmias, and often asymptomatic, while guideline-directed monitoring of serum potassium is underused. A deep-learning model that enables noninvasive hyperkalemia screening from the electrocardiogram (ECG) may improve detection of this life-threatening condition. To evaluate the performance of a deep-learning model in detection of hyperkalemia from the ECG in patients with CKD. A deep convolutional neural network (DNN) was trained using 1 576 581 ECGs from 449 380 patients seen at Mayo Clinic, Rochester, Minnesota, from 1994 to 2017. The DNN was trained using 2 (leads I and II) or 4 (leads I, II, V3, and V5) ECG leads to detect serum potassium levels of 5.5 mEq/L or less (to convert to millimoles per liter, multiply by 1) and was validated using retrospective data from the Mayo Clinic in Minnesota, Florida, and Arizona. The validation included 61 965 patients with stage 3 or greater CKD. Each patient had a serum potassium count drawn within 4 hours after their ECG was recorded. Data were analyzed between April 12, 2018, and June 25, 2018. Use of a deep-learning model. Area under the receiver operating characteristic curve (AUC) and sensitivity and specificity, with serum potassium level as the reference standard. The model was evaluated at 2 operating points, 1 for equal specificity and sensitivity and another for high (90%) sensitivity. Of the total 1 638 546 ECGs, 908 000 (55%) were from men. The prevalence of hyperkalemia in the 3 validation data sets ranged from 2.6% (n = 1282 of 50 099; Minnesota) to 4.8% (n = 287 of 6011; Florida). Using ECG leads I and II, the AUC of the deep-learning model was 0.883 (95% CI, 0.873-0.893) for Minnesota, 0.860 (95% CI, 0.837-0.883) for Florida, and 0.853 (95% CI, 0.830-0.877) for Arizona. Using a 90% sensitivity operating point, the sensitivity was 90.2% (95% CI, 88.4%-91.7%) and specificity was 63.2% (95% CI, 62.7%-63.6%) for Minnesota; the sensitivity was 91.3% (95% CI, 87.4%-94.3%) and specificity was 54.7% (95% CI, 53.4%-56.0%) for Florida; and the sensitivity was 88.9% (95% CI, 84.5%-92.4%) and specificity was 55.0% (95% CI, 53.7%-56.3%) for Arizona. In this study, using only 2 ECG leads, a deep-learning model detected hyperkalemia in patients with renal disease with an AUC of 0.853 to 0.883. The application of artificial intelligence to the ECG may enable screening for hyperkalemia. Prospective studies are warranted.

Marijuana Use and Renal Function Among US Adults

BackgroundIn recent years, the number of states that have legalized medical marijuana or retail sales has increased, bringing potential changes of marijuana use pattern among the general population. However, health effects of acute and chronic marijuana use on many relevant health outcomes, including renal function, remain largely unexamined. In this study, we aimed to assess the association between recent and past marijuana use and renal function. MethodsWe conducted a cross-sectional study among 13,995 US adults aged 18 to 59 years in the National Health and Nutrition Examination Survey from 2007 to 2014. We examined associations between marijuana use and serum creatinine concentration, estimated glomerular filtration rate (eGFR), and odds of having stage 2 or greater chronic kidney disease using weighted multivariable linear regression. ResultsIn the study population, 6483 were never users, 5499 were past users, and 2013 were current users. Marijuana use did not have a significant association with serum creatinine, eGFR, or odds of having stage 2 or greater chronic kidney disease. Serum creatinine and eGFR had an increasing trend comparing past and current users with never users that did not reach statistical significance. All associations remained unchanged in the sensitivity analysis restricted to people without cardiovascular disease. ConclusionsWe did not observe any clinically significant association between current or past self-reported marijuana use and measures of kidney function.

Risk for cognitive impairment across 22 measures of cognitive ability in early-stage chronic kidney disease.

Chronic kidney disease (CKD) is a significant risk factor for cognitive impairment. Previous studies have examined differences in cognitive impairment between persons with and without CKD using multiple cognitive outcomes, but few have done this for an extensive battery of cognitive tests. We relate early-stage CKD to two indices of impairment for 22 measures of cognitive ability. The study was community-based and cross-sectional with 898 individuals free from dementia and end-stage renal disease. Estimated glomerular filtration rate (eGFR) was calculated using the chronic kidney disease epidemiology collaboration equation and classified as <60 or ≥60 mL/min/1.73 m2, based on consensus definitions of Stage 3 or greater CKD. The eGFR classifications were related to modest [≥1 standard deviation (SD) below the mean] and severe (≥1.5 SD below the mean) impairment on each measure using logistic regression analyses adjusting for potential risk factors. A total of 146 individuals (16.3%) had eGFR <60 mL/min/1.73 m2 (mean 51.6 ± 10.1 mL/min/1.73 m2). These participants had significantly greater risk for modestly impaired abilities in the scanning and tracking and visual-spatial organization/memory (VSOM) domains after accounting for comorbidity-related risk factors [odds ratios (ORs) between 1.68 and 2.16], as well as greater risk for severely impaired functioning in the language domain (OR = 2.65). Participants with eGFR <60 mL/min/1.73 m2 were at higher risk for cognitive impairment than those with eGFR ≥60 mL/min/1.73 m2 on the majority of cognitive abilities, specifically those within the VSOM, Language, and scanning and tracking domains. Targeted screening for cognitive deficits in kidney disease patients early in their disease course may be warranted.

Warm Ischemia-Related Postoperative Renal Dysfunction in Elective Laparoscopic Partial Nephrectomy Recovers During Intermediate-Term Follow-Up.

To analyze the impact of warm ischemia time (WIT) on early postoperative and ultimate renal function after elective laparoscopic partial nephrectomy (LPN). One hundred and twenty-seven patients who underwent elective, ischemia-applied LPN were investigated in this study. The study patients were without stage 3 or greater chronic kidney disease (CKD) (estimated glomerular filtration rate [eGFR] <60 mL/min/1.73 m(2)) before LPN. Initially, the patients were grouped using the criteria of postoperative de novo stage 3 or greater CKD: Group A (n=104, eGFR ≥60 mL/min/1.73 m(2)) and group B (n=23, eGFR <60 mL/min/1.73 m(2)). The patients were also divided into two groups using 27.75 minute cutoff value obtained by receiver operating curve (ROC) analysis for WIT: Group 1 (n=69, WIT <27.75 min) and group 2 (n=58, WIT ≥27.75 min). The groups were compared with regard to demographic, perioperative, histopathologic, and renal functional outcomes. The decreased preoperative eGFR (P<0.001) and increased WIT (P=0.007), operative time (P=0.015), diabetes mellitus (DM) rate (P=0.019) and pathologic tumor size (P=0.031) were significantly different in group B. Multivariate analysis determined that independent predictors of de novo stage 3 or greater CKD in the early postoperative period were preoperative eGFR (P<0.001), WIT (P=0.014), and DM (P=0.030); meanwhile, preoperative eGFR (P=0.006) was the only independent predictor at last follow-up. Decreased median postoperative eGFR (P=0.018) and percent preserved postoperative eGFR (P=0.001) were significantly different in the increased WIT group, as well as elevated median postoperative eGFR loss (P=0.001). After similar follow-up (26 vs 23.5 months, P=0.913), the increased and limited WIT groups were not significantly different with regard to final eGFR (P=0.936), final eGFR loss (P=0.749) and percent preserved final eGFR (P=0.690). In elective LPN, increased WIT plays an important role in renal functional loss in the early postoperative period. This functional loss, however, recovered after an intermediate term follow-up period, similar to that of patients undergoing limited WIT.

VURD Syndrome—Does it Really Preserve Long-Term Renal Function?

VURD (posterior urethral valves, unilateral vesicoureteral reflux and renal dysplasia) syndrome is the combination of persistent unilateral vesicoureteral reflux associated with an ipsilateral dysplastic, poorly functioning kidney in patients with posterior urethral valves. It was postulated that this syndrome may result in preservation of long-term renal function due to a pressure release pop-off mechanism. We determined the effects of VURD long-term renal outcomes. We retrospectively reviewed the records of boys diagnosed with posterior urethral valves between 1983 and 2009 at a single pediatric tertiary hospital. Patients were divided into those with and those without VURD syndrome. The outcome of interest was renal impairment, defined as stage 3 or greater chronic kidney disease (glomerular filtration rate less than 60 ml/min/1.73 m(2)). We identified 89 patients, of whom 23 (26%) had VURD. Median followup was 77 and 57 months in the VURD and nonVURD groups, respectively. Seven patients (30%) with and 26 (39%) without VURD had significant renal impairment. Survival analysis using a Cox proportional hazard model showed no association between VURD and renal impairment (HR 1.05, 95% CI 0.65-1.70). The main predictors of renal function were the creatinine nadir and patient age at diagnosis. VURD syndrome does not seem to have a long-term protective effect on renal function.

Relationship of Left Ventricular Hypertrophy and Diastolic Function With Cardiovascular and Renal Outcomes in African Americans With Hypertensive Chronic Kidney Disease

African Americans with hypertension are at high risk for adverse outcomes from cardiovascular and renal disease. Patients with stage 3 or greater chronic kidney disease have a high prevalence of left ventricular (LV) hypertrophy and diastolic dysfunction. Our goal was to study prospectively the relationships of LV mass and diastolic function with subsequent cardiovascular and renal outcomes in the African American Study of Kidney Disease and Hypertension cohort study. Of 691 patients enrolled in the cohort, 578 had interpretable echocardiograms and complete relevant clinical data. Exposures were LV hypertrophy and diastolic parameters. Outcomes were cardiovascular events requiring hospitalization or causing death; a renal composite outcome of doubling of serum creatinine or end-stage renal disease (censoring death); and heart failure. We found strong independent relationships between LV hypertrophy and subsequent cardiovascular (hazard ratio, 1.16; 95% confidence interval, 1.05-1.27) events, but not renal outcomes. After adjustment for LV mass and clinical variables, lower systolic tissue Doppler velocities and diastolic parameters reflecting a less compliant LV (shorter deceleration time and abnormal E/A ratio) were significantly (P<0.05) associated with future heart failure events. This is the first study to show a strong relationship among LV hypertrophy, diastolic parameters, and adverse cardiac outcomes in African Americans with hypertension and chronic kidney disease. These echocardiographic risk factors may help identify high-risk patients with chronic kidney disease for aggressive therapeutic intervention.

Progression of carotid atherosclerosis in patients with systemic lupus erythematosus

The progression of carotid atherosclerosis in lupus patients is frequently encountered, and it is determined by both traditional and nontraditional risk factors. Of the 181 patients initially included in the study, 157 patients were reevaluated after 39(37-42) months. The progression of atherosclerosis was defined as the increase in the intima-media thickness (IMT) >0.15mm and/or an increase of the plaque score. The predictive factors of progression were identified using the Poisson regression model. The median of the cohort age at baseline was 38years (range 29-46years; 96.2% female, 75.8% nonwhite). Carotid atherosclerosis progression was observed in 43 patients (27.4%), an increased plaque score was observed in nine patients (5.7%), an increase of IMT >0.15mm was observed in 31 (19.7%), and both issues were present in three patients (1.9%). The univariate determinants of atherosclerosis progression were age, systemic lupus erythematosus (SLE) duration, and higher serum level of triglycerides (p < 0.05). The presence of nephrotic proteinuria (p = 0.063), stage 3 or greater chronic kidney disease (p = 0.091), and longer duration of prednisone use (p = 0.056) showed a tendency towards association with progression of atherosclerosis. The independent risk factors for progression were the SLE duration (p = 0.008, RR = 1.06, 95% CI = 1.03-1.10) and the presence of nephrotic proteinuria (p = 0.022, RR = 4.22, 95% CI = 2.18-8.15). The progression of atherosclerosis occurred in a substantial number of young SLE patients during a short-term follow-up. The independent factors associated with this progression emphasize the importance of SLE in determining atherosclerosis in these individuals.

Five to 10-Year Followup of Open Partial Nephrectomy in a Solitary Kidney

Followup is limited in patients with a solitary kidney who undergo partial nephrectomy. We evaluated overall, cancer specific and recurrence-free survival, and renal function in patients 5 years or greater after open partial nephrectomy. We retrospectively reviewed the Cleveland Clinic kidney cancer database, including only patients with a solitary kidney treated with open partial nephrectomy 5 or more years ago (from 1980 to June 2006) who had 6 months or more of followup. Survival and recurrence analyses were calculated using a Cox proportional hazards model. Results are shown as Kaplan-Meier survival curves. Linear regression analysis was done to assess postoperative renal function. A total of 282 patients fit our study inclusion criteria (mean followup 175 months), of whom 233 underwent open partial nephrectomy 10 or more years ago. Actual overall survival was 78.5% and 59.5% at 5 and 10 years, respectively. The average estimated glomerular filtration rate at 5 years or greater and 10 years or greater since open partial nephrectomy was 35.1 and 34.5 ml/minute/1.73 m(2) in 89.7% and 89.6%, respectively, of patients with stage 3 or greater chronic kidney disease. Eight survivors were on intermittent hemodialysis 5 years or more postoperatively, including 5 at 10 years or more. There were 76 recurrences for a calculated 5 and 10-year recurrence-free survival rate of 72% (95% CI 66-879) and 63% (95% CI 57-71), respectively. Open partial nephrectomy in the solitary kidney provides reliable long-term oncological control at 5 and 10 years. Predicted and actual outcomes correspond well. Although most patients have chronic kidney disease postoperatively, it appears stable with minimal progression to dialysis.

Linking clinic and home: a randomized, controlled clinical effectiveness trial of real-time, wireless blood pressure monitoring for older patients with kidney disease and hypertension.

Older adults with chronic kidney disease have a high rate of uncontrolled hypertension. Home monitoring of blood pressure (BP) is an integral part of management, but requires that patients bring records to clinic visits. Telemonitoring interventions, however, have not targeted older, less technologically-skilled populations. Veterans with stage 3 or greater chronic kidney disease and uncontrolled hypertension were randomized to a novel telemonitoring device pairing a Bluetooth-enabled BP cuff with an Internet-enabled hub, which wirelessly transmitted readings (n=28), or usual care (n=15). Home recordings were reviewed weekly and telemonitoring participants were contacted if BP was above goal. The prespecified primary endpoints were improved data exchange and device acceptability. Secondary endpoint was BP change. Forty-three participants (average age 68 years, 75% white) completed the 6-month study. Average start-of-study BP was 147/78 mmHg. Those in the intervention arm had a median of 29 (IQR 22, 53) transmitted BP readings per month, with 78% continuing to use the device regularly, whereas only 20% of those in the usual care group brought readings to in-person visits. The median number of telephone contacts triggered by the wireless monitoring was 2 (IQR 1, 4) per patient. Both groups had a significant improvement in systolic BP (P<0.05, for both changes); systolic BP fell a median of 13 mmHg in monitored participants compared with 8.5 mmHg in usual care participants (P for comparison 0.31). This low-cost wireless monitoring strategy led to greater sharing of data between patients and clinic and produced a trend toward improvements in BP control over usual care at 6 months.

Cardiorenal Anemia Syndrome as a Prognosticator for Death in Heart Failure

Anemia and chronic kidney disease are common in patients with heart failure (HF) and are associated with adverse outcomes. We analyzed the effect of cardiorenal anemia (CRA) syndrome, defined as anemia (hemoglobin <130 g/L for men, <120 g/L for women) and stage 3 or greater chronic kidney disease (estimated glomerular filtration rate <60 ml/min/1.73 m(2)), in outpatients with HF. Consecutive patients with HF were prospectively enrolled from 2000 to 2005 (n = 748). The baseline clinical characteristics, pathology test results, and medication use were compared between those with and without CRA syndrome. The primary end point was all-cause mortality. The mean follow-up was 2.5 ± 1.6 years, with a left ventricular ejection fraction <45% present in 70% of patients. Angiotensin-converting enzyme inhibitors, β blockers, and spironolactone were used in 87%, 67%, and 37%, respectively. CRA syndrome was present in 224 patients (30%). These patients had greater all-cause mortality (51% vs 26%, p <0.001), older age (mean 77 ± 8 vs 67 ± 14 years, p <0.001), and greater rates of diabetes mellitus (35% vs 23%, p <0.001) and ischemic heart disease (50% vs 35%, p <0.001). The independent predictors of mortality were CRA syndrome (hazard ratio 2.0, 95% confidence interval 1.4 to 2.8, p <0.001), left ventricular systolic dysfunction per grade (hazard ratio 1.5, 95% confidence interval 1.3 to 1.8, p <0.001), the absence of a β blocker (hazard ratio 1.6, 95% confidence interval 1.1 to 2.2, p = 0.005), New York Heart Association class per class (hazard ratio 1.5, 95% confidence interval 1.2 to 1.9, p <0.01), and age per decade (hazard ratio 1.6, 95% confidence interval 1.4 to 2.0, p <0.001). In conclusion, CRA syndrome was common in patients with HF and was an independent predictor of all-cause mortality. Consideration should be given to identifying CRA syndrome and modifying reversible factors.

Functional Recovery After Partial Nephrectomy: Effects of Volume Loss and Ischemic Injury

We used what is to our knowledge a new method to estimate volume loss after partial nephrectomy to assess the relative contributions of ischemic injury and volume loss on functional outcomes. We analyzed the records of 301 consecutive patients who underwent conventional partial nephrectomy between 2007 and 2010 with available data to meet inclusion criteria. Percent functional volume preservation was measured at a median of 1.4 years after surgery. Modification of diet in renal disease-2 estimated glomerular filtration rate was measured preoperatively and perioperatively, and a median of 1.2 years postoperatively. Statistical analysis was done to study associations. Hypothermia or warm ischemia 25 minutes or less was applied in 75% of cases. Median percent functional volume preservation was 91% (range 38%-107%). Percent glomerular filtration rate preservation at nadir and late time points was 77% and 90% of preoperative glomerular filtration rate, respectively. On multivariate analysis percent functional volume preservation and warm ischemia time were associated with nadir glomerular filtration rate while only percent functional volume preservation was associated with late glomerular filtration rate (each p <0.001). Late percent glomerular filtration rate preservation and percent functional volume preservation were directly associated (p <0.001). Recovery of function to 90% or greater of percent functional volume preservation predicted levels was observed in 86% of patients. In patients with de novo postoperative stage 3 or greater chronic kidney disease, percent functional volume preservation and Charlson score were associated with late percent glomerular filtration rate preservation. Warm ischemia time was not associated with late functional glomerular filtration rate decreases in patients considered high risk for ischemic injury. In this cohort volume loss and not ischemia time was the primary determinant of ultimate renal function after partial nephrectomy. Technical modifications aimed at minimizing volume loss during partial nephrectomy while still achieving negative margins may result in improved functional outcomes.

Surgical Management of Bilateral Synchronous Kidney Tumors: Functional and Oncological Outcomes

We evaluated renal functional and oncological outcomes after sequential partial nephrectomy and radical nephrectomy in patients with bilateral synchronous kidney tumors. A total of 220 patients treated from June 1994 to July 2008 were included in the study. Estimated glomerular filtration rate, and overall, cancer specific and recurrence-free survival were assessed. Patients underwent sequential partial nephrectomy (134), partial nephrectomy followed by radical nephrectomy (60) or radical nephrectomy followed by partial nephrectomy (26). Final estimated glomerular filtration rate after bilateral surgery was 59, 36 and 35 ml/minute/1.73 m(2) in these 3 groups, respectively (p <0.001). The order in which partial nephrectomy and radical nephrectomy were conducted did not affect functional outcomes. Overall survival of patients with bilateral cancer was 86% at 5 years and 71% at 10 years, cancer specific survival was 96% at 5 and 10 years, and recurrence-free survival was 73% at 5 years and 44% at 10 years. Overall survival was decreased in patients with tumors larger than 7 cm (p = 0.003). Patients with postoperative stage III or greater chronic kidney disease had decreased overall survival due to noncancer causes (p = 0.007). Patients treated with sequential surgery for bilateral synchronous kidney tumors have 5 and 10-year oncological outcomes comparable to those of patients with unilateral kidney cancer. Decreased overall survival was significantly associated with tumor size larger than 7 cm and postoperative stage III or greater chronic kidney disease. Nephron sparing surgery should be conducted for all amenable bilateral kidney masses given the negative impact of renal functional decline on overall survival.