Age- and Race-Specific Changes in ESKD Incidence over Four Decades.

SIGNIFICANCE STATEMENT: ESKD incidence has changed substantially in the past four decades, but differences by age and race have been unexplored. Using data from the United States Renal Data System, we found that ESKD incidence rose for Black and White teenagers, adults, and older adults for two decades beginning in 1980. Growth in incidence slowed for most groups by 1993, and by 2006, the annual percent change (APC) in ESKD incidence had declined for all groups, except White adults, for whom rates continued to rise. By 2019, ESKD incidence among Black and White adolescents nearly returned to 1980 levels, but no other group achieved that degree of improvement. Nonetheless, the ESKD incidence rate among Black American patients exceeds that of White patients in every age group. Distinct patterns in ESKD incidence among patients of different age, sex, and racial groups are shown. These findings could reflect changes in dialysis acceptance rates, access to preventive health care, incidence of diabetes mellitus, implementation of evidence-based guidelines for treatment of CKD, or other unrecognized factors. There may be population-specific opportunities to change the growth of the US ESKD population and address current racial disparities. BACKGROUND: Substantial changes in ESKD incidence over four decades among Black and White Americans of different ages have been incompletely explored. METHODS: We analyzed United States Renal Data System data from 1980 to 2019 to determine ESKD incidence trends among Black and White adolescent (13-17 years), adult (18-64 years), and older adult (≥65) populations. We used the National Cancer Institute Joinpoint Regression Program to estimate annual percent change (APC) in ESKD incidence and to define points in time where a statistically significant change in APC slope occurred for each group. RESULTS: ESKD incidence rose after 1980 for all groups, although the trends differed ( P < 0.001). Growth in incidence slowed for most by 1993, and by 2006, the APC in ESKD incidence had declined for all groups, except White adults, for whom rates continued to rise ( P < 0.05). By 2019, ESKD incidence among Black and White adolescents nearly returned to 1980 levels, but no other group achieved that degree of improvement. Nonetheless, the ESKD incidence among Black American patients exceeds that of White patients in every age group. CONCLUSIONS: Distinct patterns in ESKD incidence among patients of different age, sex, and racial groups are shown. These findings could reflect changes in dialysis acceptance rates, access to preventive health care, incidence of diabetes mellitus, implementation of evidence-based guidelines for treatment of CKD, or other unrecognized factors. PODCAST: This article contains a podcast at https://dts.podtrac.com/redirect.mp3/www.asn-online.org/media/podcast/JASN/2024_03_13_ASN0000000000000310.mp3.

Epidemiology of Infantile Ureteropelvic Junction Obstruction in the US.

OBJECTIVE: To describe sex- and diagnosis-specific comorbidities, outcomes, and secular trends associated with ureteropelvic junction obstruction (UPJO) in a large, real-world population diagnosed with hydronephrosis in infancy. MATERIALS AND METHODS: We identified all infants ≤1 year old with ≥1 claim in the Optum Clinformatics 2007-2020 nationwide population database and used univariable and multivariable Cox regression analyses to estimate associations of demographic and clinical characteristics of infants with a UPJO diagnosis with surgical status. RESULTS: Of 22,349 infants with hydronephrosis (1.1% of infants; males-1.4%, females-0.7%), 1722 (7.7%; 7.9%-males, 7.2%-females) had UPJO. Follow-up was ≥1 year in 1198 (70%) and ≥3 years in 555 (32%) cases, and UPJO repair was performed in 542 children (31.5%; 32.3%-males, 29.5%-females); 77.7% within 1 year and 97.3% within 3 years. UPJO repair was associated with prior urinary tract infection (UTI) (hazard ratio (HR) 1.41, 95% confidence interval (CI) 1.12-1.76) and South (HR 1.42, 95% CI 1.14-1.78) or Midwest (HR 1.60, 95% CI 1.26-2.04) geographic region but did not change over time. CONCLUSION: This population-based study provides a real-world view of postnatally diagnosed hydronephrosis, focusing on UPJO, for which 522 cases (∼1/3) had ≥3 years continuous coverage. UPJO-associated comorbidities were more common in females, and the frequencies of UPJO-associated surgery and comorbidities were higher than in other studies. Other than UTI, no other associated kidney or urinary tract diagnoses were associated with UPJO repair. We identified unique sex- and diagnosis-specific differences in associated comorbidities and interventions in children diagnosed with UPJO in the first year of life.

Association of Obesity, Metabolic Syndrome, and Diabetes With Urinary Incontinence and Chronic Kidney Disease: Analysis of the National Health and Nutrition Examination Survey, 2003-2020.

PURPOSE: Diabetes and obesity, components of the metabolic syndrome (MetS), are risk factors for urinary incontinence (UI) and chronic kidney disease (CKD). We interrogated US population-based data to explore independent, sex-specific associations between nondiabetic MetS, with and without obesity, and UI and/or CKD. MATERIALS AND METHODS: We analyzed data from 8586 males and 8420 females ≥20 years from the National Health and Nutrition Examination Survey. Multivariable logistic regression models were used to examine associations of UI or CKD with diabetes and 4 nondiabetic obesity/metabolic phenotypes: non-MetS/nonobese, MetS/nonobese, non-MetS/obese, and MetS/obese. Multinominal logistic regression models were used to assess associations of co-occurring UI/CKD with obesity/metabolic phenotypes. RESULTS: Male MetS/obese participants had increased odds of any UI (1.25; 95% CI 1.00-1.57) and urgency UI (1.36; 1.03-1.80), compared with non-MetS/nonobese participants. Female MetS/obese participants had increased odds of any UI (2.16; 95% CI 1.76-2.66), stress UI (1.51; 1.21-1.87), and mixed UI (1.66; 1.31-2.11) compared with non-MetS/nonobese participants. The odds of co-occurring UI/CKD were increased relative to either condition alone in persons with diabetes, and in males with MetS/obese phenotypes and females with MetS phenotypes as compared to same sex participants with neither obesity nor MetS. CONCLUSIONS: We found novel associations between MetS/obese and urgency UI in males without diabetes, and between SUI and both MetS and obesity in females without diabetes. Odds estimates for UI/CKD were increased by existing obesity or MetS as compared to those for UI or CKD alone. Improved understanding of modifiable factors associated with UI will inform prevention and treatment opportunities.

Readmission and Mortality After Hospitalization With Acute Kidney Injury.

RATIONALE & OBJECTIVE: Acute kidney injury (AKI) carries high rates of morbidity and mortality. This study quantified various short- and long-term outcomes after hospitalization with AKI. STUDY DESIGN: Retrospective propensity score (PS)-matched cohort study. SETTING & PARTICIPANTS: Optum Clinformatics, a national claims database, was used to identify patients hospitalized with and without an AKI discharge diagnosis between January 2007 and September 2020. EXPOSURE: Among patients with prior continuous enrollment for at least 2years without AKI hospitalization, 471,176 patients hospitalized with AKI were identified and PS-matched to 471,176 patients hospitalized without AKI. OUTCOME(S): All-cause and selected-cause rehospitalizations and mortality 90 and 365 days after index hospitalization. ANALYTICAL APPROACH: After PS matching, rehospitalization and death incidences were estimated using the cumulative incidence function method and compared using Gray's test. The association of AKI hospitalization with each outcome was tested using Cox models for all-cause mortality and, with mortality as competing risk, cause-specific hazard modeling for all-cause and selected-cause rehospitalization. Overall and stratified analyses were performed to evaluate for interaction between an AKI hospitalization and preexisting chronic kidney disease (CKD). RESULTS: After PS matching, AKI was associated with higher rates of rehospitalization for any cause (hazard ratio [HR], 1.62; 95% CI, 1.60-1.65), end-stage renal disease (HR, 6.21; 95% CI, 1.04-36.92), heart failure (HR, 2.81; 95% CI, 2.66, 2.97), sepsis (HR, 2.62; 95% CI, 2.49-2.75), pneumonia (HR, 1.47; 95% CI, 1.37-1.57), myocardial infarction (HR, 1.48; 95% CI, 1.33-1.65), and volume depletion (HR, 1.64; 95% CI, 1.37-1.96) at 90 days after discharge compared with the group without AKI, with similar findings at 365 days. Mortality rate was higher in the group with AKI than in the group without AKI at 90 (HR, 2.66; 95% CI, 2.61-2.72) and 365 days (HR, 2.11; 95% CI, 2.08-2.14). The higher risk of outcomes persisted when participants were stratified by CKD status (P<0.01). LIMITATIONS: Causal associations between AKI and the reported outcomes cannot be inferred. CONCLUSIONS: AKI during hospitalization in patients with and without CKD is associated with increased risk of 90- and 365-day all-cause/selected-cause rehospitalization and death.

Transplantation Mediates Much of the Racial Disparity in Survival from Childhood-Onset Kidney Failure.

BACKGROUND: The role of kidney transplantation in differential survival in Black and White patients with childhood-onset kidney failure is unexplored. METHODS: We analyzed 30-year cohort data of children beginning RRT before 18 years of age between January 1980 and December 2017 (n=28,337) in the US Renal Data System. Cox regression identified transplant factors associated with survival by race. The survival mediational g-formula estimated the excess mortality among Black patients that could be eliminated if an intervention equalized their time with a transplant to that of White patients. RESULTS: Black children comprised 24% of the cohort and their crude 30-year survival was 39% compared with 57% for White children (log rank P<0.001). Black children had 45% higher risk of death (adjusted hazard ratio [aHR], 1.45; 95% confidence interval [95% CI], 1.36 to 1.54), 31% lower incidence of first transplant (aHR, 0.69; 95% CI, 0.67 to 0.72), and 39% lower incidence of second transplant (aHR, 0.61; 95% CI, 0.57 to 0.65). Children and young adults are likely to require multiple transplants, yet even after their first transplant, Black patients had 11% fewer total transplants (adjusted incidence rate ratio [aIRR], 0.89; 95% CI, 0.86 to 0.92). In Black patients, grafts failed earlier after first and second transplants. Overall, Black patients spent 24% less of their RRT time with a transplant than did White patients (aIRR, 0.76; 95% CI, 0.74 to 0.78). Transplantation compared with dialysis strongly protected against death (aHR, 0.28; 95% CI, 0.16 to 0.48) by time-varying analysis. Mediation analyses estimated that equalizing transplant duration could prevent 35% (P<0.001) of excess deaths in Black patients. CONCLUSIONS: Equalizing time with a functioning transplant for Black patients may equalize survival of childhood-onset ESKD with White patients.

Concomitant Use of Gabapentinoids with Opioids Is Associated with Increased Mortality and Morbidity among Dialysis Patients.

BACKGROUND: The opioid epidemic is a public health emergency and appropriate medication prescription for pain remains challenging. Physicians have increasingly prescribed gabapentinoids for pain despite limited evidence supporting their use. We determined the prevalence of concomitant gabapentinoid and opioid prescriptions and evaluated their associations with outcomes among dialysis patients. METHODS: We used the United States Renal Data System to identify patients treated with dialysis with Part A, B, and D coverage for all of 2010. Patients were grouped into 4 categories of drugs exposure status in 2010: (1) no prescriptions of either an opioid or gabapentinoid, (2) ≥1 prescription of an opioid and no prescriptions of gabapentinoids, (3) no prescriptions of an opioid and ≥1 prescription of gabapenbtinoids, (4) ≥1 prescription of both an opioid and gabapentinoid. Outcomes included 2-year all-cause death, dialysis discontinuation, and hospitalizations assessed in 2011 and 2012. RESULTS: The study population included 153,758 dialysis patients. Concomitant prescription of an opioid and gabapentin (15%) was more common than concomitant prescription of an opioid and pregabalin (4%). In adjusted analyses, concomitant prescription of an opioid and gabapentin compared to no prescription of either was associated with increased risk of death (hazard ratio [HR] 1.16, 95% CI 1.12-1.19), dialysis discontinuation (HR 1.14, 95% CI 1.03-1.27), and hospitalization (HR 1.33, 95% CI 1.31-1.36). Concomitant prescription of an opioid and pregabalin compared to no prescription of either was associated with increased mortality (HR 1.22, 95% CI 1.16-1.28) and hospitalization (HR 1.37, 95% CI 1.33-1.41), but not dialysis discontinuation (HR 1.13, 95% CI 0.95-1.35). Prescription of opioids and gabepentinoids compared to only being prescribed opioids was associated with higher risk of hospitalizations, but not mortality, or dialysis discontinuation. CONCLUSIONS: Concomitant prescription of opioids and gabapentinoids among US dialysis patients is common, and both drugs have independent effects on outcomes. Future research should prospectively investigate the potential harms of such drugs and identify safer alternatives for treatment of pain in end-stage renal disease patients.

Racial/Ethnic Disparities in Atrial Fibrillation Treatment and Outcomes among Dialysis Patients in the United States.

BACKGROUND: Because stroke prevention is a major goal in the management of ESKD hemodialysis patients with atrial fibrillation, investigating racial/ethnic disparities in stroke among such patients is important to those who could benefit from strategies to maximize preventive measures. METHODS: We used the United States Renal Data System to identify ESKD patients who initiated hemodialysis from 2006 to 2013 and then identified those with a subsequent atrial fibrillation diagnosis and Medicare Part A/B/D. Patients were followed for 1 year for all-cause stroke, mortality, prescription medications, and cardiovascular disease procedures. The survival mediational g-formula quantified the percentage of excess strokes attributable to lower use of atrial fibrillation treatments by race/ethnicity. RESULTS: The study included 56,587 ESKD hemodialysis patients with atrial fibrillation. Black, white, Hispanic, and Asian patients accounted for 19%, 69%, 8%, and 3% of the population, respectively. Compared with white patients, black, Hispanic, or Asian patients were more likely to experience stroke (13%, 15%, and 16%, respectively) but less likely to fill a warfarin prescription (10%, 17%, and 28%, respectively). Warfarin prescription was associated with decreased stroke rates. Analyses suggested that equalizing the warfarin distribution to that in the white population would prevent 7%, 10%, and 12% of excess strokes among black, Hispanic, and Asian patients, respectively. We found no racial/ethnic disparities in all-cause mortality or use of cardiovascular disease procedures. CONCLUSIONS: Racial/ethnic disparities in all-cause stroke among hemodialysis patients with atrial fibrillation are partially mediated by lower use of anticoagulants among black, Hispanic, and Asian patients. The reasons for these disparities are unknown, but strategies to maximize stroke prevention in minority hemodialysis populations should be further investigated.

Psychiatric Illness and Mortality in Hospitalized ESKD Dialysis Patients.

BACKGROUND AND OBJECTIVES: Limited existing data on psychiatric illness in ESKD patients suggest these diseases are common and burdensome, but under-recognized in clinical practice. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: We examined hospitalizations with psychiatric diagnoses using inpatient claims from the first year of ESKD in adult and pediatric Medicare recipients who initiated treatment from 1996 to 2013. We assessed associations between hospitalizations with psychiatric diagnoses and all-cause death after discharge in adult dialysis patients using multivariable-adjusted Cox proportional hazards regression models. RESULTS: In the first ESKD year, 72% of elderly adults, 66% of adults and 64% of children had at least one hospitalization. Approximately 2% of adults and 1% of children were hospitalized with a primary psychiatric diagnosis. The most common primary psychiatric diagnoses were depression/affective disorder in adults and children, and organic disorders/dementias in elderly adults. Prevalence of hospitalizations with psychiatric diagnoses increased over time across groups, primarily from secondary diagnoses. 19% of elderly adults, 25% of adults and 15% of children were hospitalized with a secondary psychiatric diagnosis. Hazards ratios of all-cause death were higher in all dialysis adults hospitalized with either primary (1.29; 1.26 to 1.32) or secondary (1.11; 1.10 to 1.12) psychiatric diagnoses than in those hospitalized without psychiatric diagnoses. CONCLUSIONS: Hospitalizations with psychiatric diagnoses are common in pediatric and adult ESKD patients, and are associated with subsequent higher mortality, compared with hospitalizations without psychiatric diagnoses. The prevalence of hospitalizations with psychiatric diagnoses likely underestimates the burden of mental illness in the population.

Epilepsy and antiseizure medications increase all-cause mortality in dialysis patients in the United States.

Seizures have been associated with uremia, but there are few data regarding the prevalence, treatment, and outcomes of patients with end-stage renal disease (ESRD) with epilepsy compared to those with ESRD without epilepsy. Here we conducted a retrospective cohort study using the United States Renal Data System to assess mortality and antiseizure medication prescriptions among patients with ESRD with and without a diagnosis of epilepsy. A modified Poisson regression with a robust variance was used to estimate the association between epilepsy status and mortality, and evaluate effect modification by neurology consultation. Additionally antiseizure medications were assessed in relation to mortality among those with epilepsy. Of 148,294 patients with ESRD in the cohort, 13,094 (8.8%) met a claims-based definition for epilepsy. Among those with epilepsy, 80.9% filled an anticonvulsant or hydantoin prescription in 2013-2014, compared to 33.3% without epilepsy. After adjustment for confounders, the mortality risk among those with epilepsy was 1.11 (95% confidence interval: 1.07, 1.14) times higher than those without. An epilepsy diagnosis was associated with a 15% increase in mortality risk among patients who did not have a neurology consultation (relative risk: 1.15 [95% confidence interval: 1.10, 1.20]), but this risk was attenuated among patients with a neurology consultation (1.07 [1.03, 1.11]). Prescription of gabapentin to patients with an epilepsy diagnosis compared to other antiseizure medications was associated with increased mortality (1.08 [1.01, 1.15]). Thus, patients with ESRD treated with dialysis have a high prevalence of epilepsy, which was associated with increased mortality risk compared to those without epilepsy. Hence, appropriate multidisciplinary care, treatment, and medication selection may reduce mortality among dialysis patients with epilepsy.

p-Phosphonic acid calix[8]arene mediated synthesis of ultra-large, ultra-thin, single-crystal gold nanoplatelets.

Single-crystal Au nanoplatelets, as large as 28 µm in cross section and as thin as 6 nm, are generated by bubbling hydrogen gas into an aqueous solution of HAuCl4 in the presence of p-phosphonic acid calix[8]arene, which acts as both a catalyst and stabiliser. The use of the ultrathin Au nanoplatelets in oxygen gas sensing has also been established.

Opioid Prescription, Morbidity, and Mortality in US Transplant Recipients.

BACKGROUND: Centers for Disease Control and Prevention guidelines recommend caution in prescribing opioids for chronic pain. The characteristics of opioid prescription (OpRx) among kidney transplant (KTx) recipients have not been described in a national population. METHODS: We assessed OpRx prevalence among prevalent KTx recipients, and associated duration (long-term, defined as ≥90 days in a year) and dosing (in morphine milligram equivalents per day of <50, 50-89, and ≥90) with outcomes, death and graft loss, among incident KTx recipients using 2006-2010 US Renal Data System files, including Medicare Part D for medication ascertainment. Cox models controlled for recipient factors. RESULTS: Of 36,486 KTx recipients in the 2010 prevalent cohort, approximately 14.6% had long-term OpRx. The strongest association with long-term OpRx after KTx was long-term OpRx before KTx (64%; adjusted odds ratio, 95% confidence interval, 95.2, 74.2-122.1). Incident KTx recipients with long-term OpRx had increased risk of mortality and graft loss compared with those without OpRx or short-term OpRx after KTx. This risk was highest among recipients with long-term OpRx doses of ≥90 morphine milligram equivalents or higher per day (adjusted hazard ratio, 95% confidence interval, 1.61, 1.24-2.10 for death, and 1.33, 1.05-1.67 for graft loss, respectively). CONCLUSIONS: In contrast to either no or short-term OpRx, long-term, and especially long-term high-dose OpRx, is associated with increased risk of death and graft loss in US KTx recipients. Causal relationships cannot be inferred, and OpRx may be an illness marker. Nevertheless, efforts to treat pain effectively in KTx recipients with less toxic interventions and decrease OpRx deserve consideration.

Opioid Prescription, Morbidity, and Mortality in United States Dialysis Patients.

Aggressive pain treatment was advocated for ESRD patients, but new Centers for Disease Control and Prevention guidelines recommend cautious opioid prescription. Little is known regarding outcomes associated with ESRD opioid prescription. We assessed opioid prescriptions and associations between opioid prescription and dose and patient outcomes using 2006-2010 US Renal Data System information in patients on maintenance dialysis with Medicare Part A, B, and D coverage in each study year (n=671,281, of whom 271,285 were unique patients). Opioid prescription was confirmed from Part D prescription claims. In the 2010 prevalent cohort (n=153,758), we examined associations of opioid prescription with subsequent all-cause death, dialysis discontinuation, and hospitalization controlled for demographics, comorbidity, modality, and residence. Overall, >60% of dialysis patients had at least one opioid prescription every year. Approximately 20% of patients had a chronic (≥90-day supply) opioid prescription each year, in 2010 usually for hydrocodone, oxycodone, or tramadol. In the 2010 cohort, compared with patients without an opioid prescription, patients with short-term (1-89 days) and chronic opioid prescriptions had increased mortality, dialysis discontinuation, and hospitalization. All opioid drugs associated with mortality; most associated with worsened morbidity. Higher opioid doses correlated with death in a monotonically increasing fashion. We conclude that opioid drug prescription is associated with increased risk of death, dialysis discontinuation, and hospitalization in dialysis patients. Causal relationships cannot be inferred, and opioid prescription may be an illness marker. Efforts to treat pain effectively in patients on dialysis yet decrease opioid prescriptions and dose deserve consideration.

Multifunctional nanoparticles for co-delivery of paclitaxel and carboplatin against ovarian cancer by inactivating the JMJD3-HER2 axis.

Ovarian cancer (OC) is the most lethal gynecologic cancer. Survival statistics have show no significant developments over the last three decades, highlighting the fact that current therapeutic strategies require substantial improvements. In this study, we designed a novel folic acid-PEG-conjugated p-phosphonated calix[4]arene nanoparticle (Fp-PCN) for the simultaneous delivery of paclitaxel (PAC) and carboplatin (CAR) at an optimal ratio (5 : 1, mol : mol) to utilize their potential synergistic effect against OC cells. The Fp-PCNs loaded with PAC and CAR (Fp-PCNPAC+CAR) resulted in a remarkable efficacy in the suppression of OC, both in vitro and in vivo. Compared to free drugs, Fp-PCNPAC+CAR showed stronger apoptosis induction as well as invasion and self-renewal capacity suppression in SKOV-3 cells. The molecular mechanism to address the synergism is that Fp-PCNPAC+CAR downregulated JMJD3 expression to modulate the H3K27me3 epigenetic mark of the promoters of HER2 and MYCN. Furthermore, the expressions of JMJD3 and HER2 were significantly associated with poor outcomes for ovarian patients. Our study demonstrates that co-delivery of PAC and CAR can be achieved with the Fp-PCNs, and reveals a previously unrecognized and unexpected role of the JMJD3-HER2 signaling axis in PAC and CAR treatment of OC.

Patients receiving frequent hemodialysis have better health-related quality of life compared to patients receiving conventional hemodialysis.

Most patients with end-stage kidney disease value their health-related quality of life (HRQoL) and want to know how it will be affected by their dialysis modality. We extended the findings of two prior clinical trial reports to estimate the effects of frequent compared to conventional hemodialysis on additional measures of HRQoL. The Daily Trial randomly assigned 245 patients to receive frequent (six times per week) or conventional (three times per week) in-center hemodialysis. The Nocturnal Trial randomly assigned 87 patients to receive frequent nocturnal (six times per week) or conventional (three times per week) home hemodialysis. All patients were on conventional hemodialysis prior to randomization, with an average feeling thermometer score of 70 to 75 (a visual analog scale from 0 to 100 where 100 is perfect health), an average general health scale score of 40 to 47 (a score from 0 to 100 where 100 is perfect health), and an average dialysis session recovery time of 2 to 3 hours. Outcomes are reported as the between-treatment group differences in one-year change in HRQoL measures and analyzed using linear mixed effects models. After one year in the Daily Trial, patients assigned to frequent in-center hemodialysis reported a higher feeling thermometer score, better general health, and a shorter recovery time after a dialysis session compared to standard thrice-weekly dialysis. After one year in the Nocturnal Trial, patients assigned to frequent home hemodialysis also reported a shorter recovery time after a dialysis session, but no statistical difference in their feeling thermometer or general health scores compared to standard home dialysis schedules. Thus, patients receiving day or nocturnal hemodialysis on average recovered approximately one hour earlier from a frequent compared to conventional hemodialysis session. Patients treated in an in-center dialysis facility reported better HRQoL with frequent compared to conventional hemodialysis.

p-Phosphonated Calix[n]arene Stabilizes Superparamagnetic Nanoparticles for Nitrate and Phosphate Uptake.

Highly faceted superparamagnetic magnetite nanoparticles roughly 11 nm in diameter are readily accessible in the presence of p-phosphonated calix[n]arenes of different ring sizes (n=4, 5 and 6), through the use of a simple co-precipitation technique. In contrast, the larger calix[8]arene affords spherical particles of comparable size. The maximum magnetization is 70-60 emu g-1 , which decreases with increasing size of the calixarene macrocycle, and the evidence indicates that the calixarenes bind to the surface of the nanoparticles via the phosphonate head groups rather than the phenolic oxygen centers. The stabilized nanoparticles show dual functionality: they remove up to 62 % of nitrate nitrogen and 48 % of phosphate from an aqueous effluent after 24 hours at concentrations of only 1 g L-1 of calixarene-coated nanoparticles.

Comparison of trends in colorectal cancer screening in the US end-stage renal disease population and the US Medicare population.

BACKGROUND: Although patients treated with maintenance hemodialysis are at an increased risk of colorectal cancer compared with the general population, national practices for colorectal cancer screening have not been reported in this population. We assessed the performance of colorectal cancer screening in the US end-stage renal disease program in comparison with the US Medicare population. METHODS: We studied the United States Renal Data System for US prevalent hemodialysis patients between 2002 and 2011 who had Medicare as their primary insurer. We assessed procedure codes for performance of common colorectal cancer screening tests, including fecal occult blood testing, sigmoidoscopy and colonoscopy. We assessed screening sigmoidoscopy and screening colonoscopy only and excluded patients who had preexisting colon cancer or gastrointestinal hemorrhage. Because colorectal cancer screening recommendations are established for hemodialysis patients who have been listed for kidney transplantation, but no general recommendations exist for patients who are not wait-listed, we assessed colorectal cancer screening separately for the two groups. RESULTS: We found that 1-year performance of colonoscopy in wait-listed hemodialysis patients was similar to or higher than that in general Medicare patients of the same age, while performance of colonoscopy in non-wait-listed patients was significantly lower than among general Medicare patients of the same age. CONCLUSIONS: Given improved survival among hemodialysis patients in the last decade, the utility of colorectal cancer screening even among non-wait-listed hemodialysis patients should be reassessed.