Surgical intervention and long-term renal outcomes of congenital ureteropelvic junction obstruction in a young adult cohort.

PURPOSE: To evaluate the impact of surgical intervention on long-term renal outcomes for adult patients with congenital ureteropelvic junction obstruction (UPJO). METHODS: We queried service members diagnosed with UPJO from the United States Military Health System electronic health records from 2005 to 2020. We assessed demographic, laboratory, radiology, surgical intervention, and outcome data. We evaluated the impact of surgical intervention on renal function based on the estimated glomerular filtration rate (eGFR), hypertension (HTN, defined as any prescription for blood pressure [BP] medication and/or average of two BP readings ≥ 130/80 mmHg more than 2 weeks apart), and changes in renal excretory function on radionuclide scans. RESULTS: We identified 108 individuals diagnosed with congenital UPJO; mean follow-up of 7 years. Mean age at diagnosis was 25 years; 95% male; 69% White, 15% Black. At diagnosis, median BP was 130/78 mmHg and mean eGFR 93 ml/min/1.73m2. Subsequently, 85% had pyeloplasty and 23% had stent placement. There were no significant differences in mean eGFR pre- and post-intervention (94 vs. 93 ml/min/1.73m2, respectively; p = 0.15) and prevalence of defined HTN (59% vs. 61%, respectively; p = 0.20). Surgical intervention for right-sided UPJO significantly reduced the proportion of patients with delayed cortical excretion (54% pre vs. 35% post, p = 0.01) and T½ emptying time (35 min vs. 19 min, p = 0.009). Similar trends occurred with left-sided UPJO but were not significant. CONCLUSION: Surgical intervention was not associated with significant differences in the long-term outcomes of kidney function and HTN prevalence in our young adult cohort. However, renal excretory function improved on radionuclide scans.

Protected Time for Program Administration among Nephrology Program Leadership in the United States.

BACKGROUND: In 2022, the Accreditation Council for Graduate Medical Education reduced minimum program director protected time for program administration from 10 to 8 h/wk, with no core faculty requirement. We surveyed program leaders regarding the effect of these changes. METHODS: This is an anonymous, online survey of all US adult nephrology program directors (March 2023), who forwarded core faculty/associate program director (APD) surveys. The questions included protected time in 2022-2023 and 2021-2022, whether it was sufficient, estimated time needed, and two validated single-item burnout measures (emotional exhaustion and depersonalization). The analysis was descriptive. RESULTS: Program directors: Their response was 62% (92/149), with geographic distribution/approved fellow positions similar to those nationally. Overall, protected time slightly increased from 2021 to 2022, largely in >6-fellow programs, but 42% (13/31) of these were still not meeting minimum requirements. Only 37% (30/81) agreed that they had sufficient protected time. Those with ≤6 fellows estimated needing 11±4 h/wk (15±4 h/wk with >6 fellows). Twenty-five percent (20/81) reported high levels of emotional exhaustion. Core faculty: 57 of 149 program directors (38%) forwarded the link to 454 faculty. Ninety-four percent of APDs (49/52) responded, reported 3±3 h/wk protected time (42% had none), and estimated needing 6±3 h/wk, regardless of program size. Sixty-seven of 402 core faculty (17%) responded, reported 2±3 h/wk (50% had none), and estimated needing 5±3 h/wk, regardless of program size. ≥85% of APDs and core faculty precepted clinical rotations, gave lectures, evaluated fellows, mentored scholarly work, and participated in recruitment. The majority assisted in fellow remediation. Thirty-four percent (15/44) of APDs and 21% (13/61) of core faculty reported high levels of emotional exhaustion. CONCLUSIONS: Program leaders estimated minimum necessary program administration times (on the basis of program size) that exceeded the Accreditation Council for Graduate Medical Education requirements. APDs/core faculty contributed substantially to nonclinical training. Thirty-four percent of APDs and 25% of program directors had a high likelihood of burnout.

Adapting an Objective Structured Clinical Examination (OSCE) on Conducting Difficult Conversations Between Nephrology Fellows and Patients to a Virtual Platform: A Research Letter.

Background: We previously described a nephrology-specific "Breaking Bad News" Objective Structured Clinical Examination (OSCE) assessing nephrology fellow communication and counseling skills in 3 scenarios: kidney replacement therapy (KRT) in kidney failure, urgent KRT in acute kidney injury (AKI), and kidney biopsy (KBx). Objective: The main objectives of this study is to adapt the OSCE to a virtual platform, simulating nephrology patient telemedicine encounters involving difficult conversations, and to assess fellow and faculty satisfaction with the virtual format. Design: Description of a formative telemedicine simulation for nephrology fellows. Setting: Fully virtual simulation conducted by 2 academic medical simulation centers. Participants: Nephrology faculty and fellows at 3 urban/suburban training programs in the eastern United States. Measurements: Description of the virtual OSCE process. Fellow and faculty satisfaction overall and for each scenario. Faculty and fellow estimates of frequency of virtual patient encounters in the past year. Methods: The OSCE consisted of 3 scenarios: KRT in kidney failure, urgent KRT in AKI, and KBx. Objective Structured Clinical Examinations were administered in May 2021. Each scenario lasted 20 minutes. The AKI scenario was audio only. Fellows telephoned a simulated patient surrogate for urgent KRT consent. Kidney failure and KBx scenarios were video encounters. Faculty observed while muted/video off. Immediately after the OSCE, fellows and faculty were anonymously surveyed regarding their satisfaction with each scenario, the OSCE overall, and their estimate of outpatient encounters and inpatient KRT counseling done virtually in the preceding year. Results: Seventeen fellows completed the OSCE at 2 centers (3 programs). Sixteen (94%) completed the survey. Almost 94% rated the OSCE as a good/very good approximation of telemedicine encounters. Those satisfied/very satisfied with each scenario are as follow: 100% for AKI, 75% for kidney failure, and 75% for KBx. Two commented that they often did urgent KRT counseling by telephone. Fellows estimated a median 20% (interquartile range: 175, 50%) of counseling for acute inpatient KRT and a median 50% (IQR: 33.75, 70%) of outpatient encounters were virtual in the prior year. Two (regarding the kidney failure and KBx scenarios) indicated they would not have counseled similar outpatients virtually. Limitations: The 15-minute interactions may be too short to allow the encounter to be completed comfortably. A small number of programs and fellows participated, and programs were located in urban/suburban areas on the east coast of the United States. Conclusions: Overall, fellows felt that the OSCE was a good approximation of virtual encounters. The OSCE is an opportunity for fellows to practice telemedicine communication skills.

Contexte: Nous avions précédemment décrit un examen clinique objectif structuré (ECOS) de type « annonce d'une mauvaise nouvelle ¼ en néphrologie afin d'évaluer les compétences en communication et consultation des résidents en néphrologie. L'ECOS comportait trois scénarios: thérapie de remplacement rénal (TRR) pour l'insuffisance rénale, TRR urgente dans les cas d'insuffisance rénale aiguë (IRA), et biopsie du rein (BxR). Objectifs: Adapter l'ECOS à une plateforme virtuelle, simuler des rencontres de télémédecine impliquant des conversations difficiles avec des patients en néphrologie, et évaluer la satisfaction des résidents en néphrologie et du corps enseignant à l'égard du format virtuel. Conception: Description d'une simulation de télémédecine pour la formation des résidents en néphrologie. Cadre: Des simulations entièrement virtuelles réalisées dans deux centers universitaires de simulation médicale. Participants: Les professeurs et les résidents en néphrologie de trois programs de formation urbains/suburbains de l'est des États-Unis. Mesures: Description du processus de l'ECOS virtuel. Satisfaction générale des résidents en néphrologie et du corps enseignant pour chacun des scénarios. Estimation, par les professeurs et les résidents, de la fréquence des rencontres virtuelles avec des patients au cours de la dernière année. Méthodologie: L'ECOS était composé de trois scénarios: TRR en insuffisance rénale; TRR urgente en contexte d'IRA et biopsie rénale. Les ECOS ont été réalisés en mai 2021. Chaque scénario durait 20 minutes. Le scénario IRA était audio uniquement; les boursiers devaient téléphoner à un patient simulé afin d'obtenir un consentement pour une TRR urgente. Les scénarios pour l'insuffisance rénale terminale et la BxR étaient sous forme de rencontres vidéo. Les professeurs observaient les scénarios en sourdine/hors vidéo. Immédiatement après l'ECOS, les résidents en néphrologie et les professeurs ont été interrogés de façon anonyme sur leur satisfaction à l'égard de chaque scénario et de l'ECOS dans son ensemble. Ils ont également été invités à estimer le nombre de consultations externes et de conseils prodigués sur la TRR à des patients hospitalisés au cours de l'année précédente. Résultats: Dix-sept résidents en néphrologie ont complété l'ECOS dans les deux centers (trois programs) et seize (94 %) ont répondu au sondage. La très grande majorité (94 %) a évalué l'ECOS comme une bonne/très bonne simulation des rencontres de télémédecine. Le taux de personnes satisfaites/très satisfaites s'établissait à 100 % pour le scénario de l'IRA, à 75 % pour celui de l'insuffisance rénale terminale et à 75 % pour celui de la BxR. Deux personnes ont dit faire régulièrement des consultations par téléphone pour la TRR urgente. Les résidents en néphrologie ont estimé que 20 %, (proportion médiane) ÉIQ= 175; 50 %, des consultations avec des patients hospitalisés et 50 %, (proportion médiane) ÉIQ = 33,75; 70 %, des consultations externes avaient été faites virtuellement au cours de l'année précédente. Pour les scénarios d'insuffisance rénale terminale et de BxR, deux personnes ont indiqué qu'elles ne feraient pas de consultations virtuelles pour ces patients. Limites: Les interactions de 15 minutes sont probablement trop courtes pour compléter confortablement la rencontre. Un faible nombre de programs et de résidents en néphrologie ont participé. Les programs évalués se situaient en zones urbaines et suburbaines de la côte est des États-Unis. Conclusion: Dans l'ensemble, les résidents en néphrologie ont estimé que l'ECOS était une bonne représentation des rencontres virtuelles. L'ECOS est une occasion pour les résidents de mettre en pratique leurs compétences en communication dans un contexte de télémédecine.

Nephrology Program Director Protected Time for Program Administration in the United States.

BACKGROUND AND OBJECTIVES: The Accreditation Council for Graduate Medical Education (ACGME) required that program directors receive 10-20 h/wk of protected time for program administration (including didactic teaching). In July 2022, this was reduced for all internal medicine subspecialties on the basis of program size, with 8 h/wk required for programs with fewer than seven fellows, the majority of nephrology programs. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: We surveyed all 151 US adult nephrology program directors (ACGME Public List of Programs 2021-2022) to determine how much protected time they receive, how much they think is necessary, and the division of their professional time. The anonymous 20-question online survey was administered from March 31 to April 30, 2022. The analysis was descriptive. RESULTS: Response rate was 66% (99 of 151). Geographic distribution and approved fellow positions were similar to programs nationally; 59% had fewer than seven approved positions. Median protected time was 10 h/wk (interquartile range, 5-10), with 8 h/wk (interquartile range, 5-10) for those with fewer than seven positions. Program directors estimated needing 12 h/wk (interquartile range, 10-16) to effectively administer programs, including those with fewer than seven positions, a median 5 h/wk (interquartile range, 0-7) more than received. Of program directors reporting <10 h/wk for program administration, 62% provided >20 hours of direct patient care. Thirty-nine percent had no protected time for core faculty. Fellow recruitment (68%) was the most time-consuming task, and didactic teaching (80%) was the most professionally rewarding. CONCLUSIONS: Approximately half of the nephrology programs surveyed were not in compliance with the ACGME-stipulated 10-h/wk minimum protected time for the 2021-2022 training year. Program directors estimated a median of 12 h/wk are needed to effectively manage programs.

Assessing Nephrology Fellows' Skills in Communicating About Kidney Replacement Therapy and Kidney Biopsy: A Multicenter Clinical Simulation Study on Breaking Bad News.

RATIONALE & OBJECTIVE: Interpersonal communication skills and professionalism competencies are difficult to assess among nephrology trainees. We developed a formative "Breaking Bad News" simulation and implemented a study in which nephrology fellows were assessed with regard to their skills in providing counseling to simulated patients confronting the need for kidney replacement therapy (KRT) or kidney biopsy. STUDY DESIGN: Observational study of communication competency in the setting of preparing for KRT for kidney failure, for KRT for acute kidney injury (AKI), or for kidney biopsy. SETTING & PARTICIPANTS: 58 first- and second-year nephrology fellows assessed during 71 clinical evaluation sessions at 8 training programs who participated in an objective structured clinical examination of simulated patients in 2017 and 2018. PREDICTORS: Fellowship training year and clinical scenario. OUTCOME: Primary outcome was the composite score for the "overall rating" item on the Essential Elements of Communication-Global Rating Scale 2005 (EEC-GRS), as assessed by simulated patients. Secondary outcomes were the score for EEC-GRS "overall rating" item for each scenario, score < 3 for any EEC-GRS item, Mini-Clinical Examination Exercise (Mini-CEX) score < 3 on at least 1 item (as assessed by faculty), and faculty and fellow satisfaction with simulation exercise (via a survey they completed). ANALYTICAL APPROACH: Nonparametric tests of hypothesis comparing performance by fellowship year (primary goal) and scenario. RESULTS: Composite scores for EEC-GRS overall rating item were not significantly different between fellowship years (P = 0.2). Only 4 of 71 fellow evaluations had an unsatisfactory score for the EEC-GRS overall rating item on any scenario. On Mini-CEX, 17% scored < 3 on at least 1 item in the kidney failure scenario; 37% and 53% scored < 3 on at least 1 item in the AKI and kidney biopsy scenarios, respectively. In the survey, 96% of fellows and 100% of faculty reported the learning objectives were met and rated the experience good or better in 3 survey rating questions. LIMITATIONS: Relatively brief time for interactions; limited familiarity with and training of simulated patients in use of EEC-GRS. CONCLUSIONS: The fellows scored highly on the EEC-GRS regardless of their training year, suggesting interpersonal communication competency is achieved early in training. The fellows did better with the kidney failure scenario than with the AKI and kidney biopsy scenarios. Structured simulated clinical examinations may be useful to inform curricular choices and may be a valuable assessment tool for communication and professionalism.

Liver Function Enzymes are Potential Predictive Markers for Kidney Allograft Dysfunction.

INTRODUCTION: Biopsy of the allograft is the gold standard for assessing kidney allograft dysfunction. The aim of our pilot study was to identify serum biomarkers that could obviate the need for biopsy. MATERIALS AND METHODS: We conducted a study to identify the biomarkers in the serum from different groups of chronic kidney disease (CKD) patients and kidney transplanted patients vs. healthy individuals. The four groups (n=25 in each group) were as follows: 1) Patients with unstable kidney allograft transplants requiring biopsy for cause, 2) Patients with stable kidney allograft transplants, 3) Patients with CKD not on immunosuppressive therapy and, 4) healthy subjects. We measured the activity and level of serum alkaline phosphatase (ALP) and other liver enzymes (alanine transaminase (ALT) and aspartate transaminase (AST)) as potential serum biomarkers in acute allograft dysfunction. RESULTS: We found that ALP correlated with allograft biopsy findings, liver function, and clinical outcomes and possibly graft survival. Additionally, AST and ALT were higher in patients with graft rejection compared to non-rejected and stable kidney transplants. Moreover, the low Pearson correlations (r- values) between ALP level with age (r=0.179), gender, body mass index (r=0.236), creatinine (r=0.044) or estimated glomerular filtration rate (r=0.048) suggest that ALP may be an independent biomarker which is relatively unaffected by other individual-level variables. CONCLUSION: ALP may be a putative biomarker to predict kidney allograft function and rejection. Data also indicated that liver function plays an important role for the overall success of kidney transplantation.

The Electronic Medical Record and Nephrology Fellowship Education in the United States: An Opinion Survey.

BACKGROUND AND OBJECTIVES: An unintended consequence of electronic medical record use in the United States is the potential effect on graduate physician training. We assessed educational burdens and benefits of electronic medical record use on United States nephrology fellows by means of a survey. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: We used an anonymous online opinion survey of all United States nephrology program directors (n=148), their faculty, and fellows. Program directors forwarded survey links to fellows and clinical faculty, indicating to how many they forwarded the link. The three surveys had parallel questions to permit comparisons. RESULTS: Twenty-two percent of program directors (n=33) forwarded surveys to faculty (n=387) and fellows (n=216; 26% of United States nephrology fellows). Faculty and fellow response rates were 25% and 33%, respectively; 51% of fellows agreed/strongly agreed that the electronic medical record contributed positively to their education. Perceived positive effects included access flexibility and ease of obtaining laboratory/radiology results. Negative effects included copy-forward errors and excessive, irrelevant documentation. Electronic medical record function was reported to be slow, disrupted, or completely lost monthly or more by >40%, and these were significantly less likely to agree that the electronic medical record contributed positively to their education. Electronic medical record completion time demands contributed to fellow reluctance to do procedures (52%), participate in conferences (57%), prolong patient interactions (74%), and do patient-directed reading (55%). Sixty-five percent of fellows reported often/sometimes exceeding work-hours limits due to documentation time demands; 85% of faculty reported often/sometimes observing copy-forward errors. Limitations include potential nonresponse and social desirability bias. CONCLUSIONS: Respondents reported that the electronic medical record enhances fellow education with efficient and geographically flexible patient data access, but the time demands of data and order entry reduce engagement in educational activities, contribute to work-hours violations, and diminish direct patient interactions.

Association of Race and Poverty With Mortality Among Nursing Home Residents on Maintenance Dialysis.

OBJECTIVES: The association of race, ethnicity, and socioeconomic factors with survival rates of nursing home (NH) residents with treated end-stage renal disease (ESRD) is unclear. We examined whether race/ethnicity, ZIP code-level, and individual-level indicators of poverty relate to mortality of NH residents on dialysis. DESIGN: Retrospective cohort study. PARTICIPANTS/SETTING: Using the United States Renal Data System database, we identified 56,194 nursing home residents initiated on maintenance dialysis from January 1, 2007 through December 31, 2013, followed until May 31, 2014. MEASUREMENTS: We evaluated baseline characteristics of the NH cohort on dialysis, including race and ethnicity. We assessed the Medicare-Medicaid dual eligibility status as an indicator of individual-level poverty and ZIP code-level median household income (MHI) data. We conducted Cox regression analyses with all-cause mortality as the outcome variable, adjusted for clinical and sociodemographic factors including end-of-life preferences. RESULTS: Adjusted Cox analysis showed a significantly lower risk of death among black vs nonblack NH residents [adjusted hazard ratio (AHR) 0.91, 95% confidence interval (CI) 0.89, 0.94]. Dual-eligibility status was significantly associated with lower risk of death compared to those with Medicare alone (AHR 0.80, 95% CI 0.78, 0.82). Compared to those in higher MHI quintile levels, NH ESRD patients in the lowest quintile were significantly associated with higher risk of death (AHR 1.09, 95% CI 1.06, 1.13). CONCLUSIONS/IMPLICATIONS: Black and Hispanic NH residents on dialysis had an apparent survival advantage. This "survival paradox" occurs despite well-documented racial/ethnic disparities in ESRD and NH care and warrants further exploration that could generate new insights into means of improving survival of all NH residents on dialysis. Area-level indicator of poverty was independently associated with mortality, whereas dual-eligibility status for Medicare and Medicaid was associated with lower risk of death, which could be partly explained by improved access to care.

The dialysis orders objective structured clinical examination (OSCE): a formative assessment for nephrology fellows.

BACKGROUND: Few quantitative nephrology-specific simulations assess fellow competency. We describe the development and initial validation of a formative objective structured clinical examination (OSCE) assessing fellow competence in ordering acute dialysis. METHODS: The three test scenarios were acute continuous renal replacement therapy, chronic dialysis initiation in moderate uremia and acute dialysis in end-stage renal disease-associated hyperkalemia. The test committee included five academic nephrologists and four clinically practicing nephrologists outside of academia. There were 49 test items (58 points). A passing score was 46/58 points. No item had median relevance less than 'important'. The content validity index was 0.91. Ninety-five percent of positive-point items were easy-medium difficulty. Preliminary validation was by 10 board-certified volunteers, not test committee members, a median of 3.5 years from graduation. The mean score was 49 [95% confidence interval (CI) 46-51], κ = 0.68 (95% CI 0.59-0.77), Cronbach's α = 0.84. RESULTS: We subsequently administered the test to 25 fellows. The mean score was 44 (95% CI 43-45); 36% passed the test. Fellows scored significantly less than validators (P < 0.001). Of evidence-based questions, 72% were answered correctly by validators and 54% by fellows (P = 0.018). Fellows and validators scored least well on the acute hyperkalemia question. In self-assessing proficiency, 71% of fellows surveyed agreed or strongly agreed that the OSCE was useful. CONCLUSIONS: The OSCE may be used to formatively assess fellow proficiency in three common areas of acute dialysis practice. Further validation studies are in progress.

Survival Disparity of African American Versus Non-African American Patients With ESRD Due to SLE.

BACKGROUND: A recent study showed an increased risk of death in African Americans compared with whites with end-stage renal disease (ESRD) due to lupus nephritis (LN). We assessed the impact of age stratification, socioeconomic factors, and kidney transplantation on the disparity in patient survival among African American versus non-African American patients with LN-caused ESRD, compared with other causes. STUDY DESIGN: Retrospective cohort study. SETTING & PARTICIPANTS: Using the US Renal Data System database, we identified 12,352 patients with LN-caused ESRD among 1,132,202 patients who initiated maintenance dialysis therapy from January 1, 1995, through December 31, 2006, and were followed up until December 31, 2010. PREDICTORS: Baseline demographics and comorbid conditions, Hispanic ethnicity, socioeconomic factors (employment status, Medicare/Medicaid insurance, and area-level median household income based on zip code as obtained from the 2000 US census), and kidney transplantation as a time-dependent variable. OUTCOME: All-cause mortality. MEASUREMENTS: Multivariable Cox and competing-risk regressions. RESULTS: Mean duration of follow-up in the LN-caused ESRD and other-cause ESRD cohorts were 6.24±4.20 (SD) and 4.06±3.61 years, respectively. 6,106 patients with LN-caused ESRD (49.43%) and 853,762 patients with other-cause ESRD (76.24%) died during the study period (P<0.001). Patients with LN-caused ESRD were significantly younger (mean age, 39.92 years) and more likely women (81.65%) and African American (48.13%) than those with other-cause ESRD. In the fully adjusted multivariable Cox regression model, African American (vs non-African American) patients with LN-caused ESRD had significantly increased risk of death at age 18 to 30 years (adjusted HR, 1.43; 95% CI, 1.24-1.65) and at age 31 to 40 years (adjusted HR, 1.17; 95% CI, 1.02-1.34). Among patients with other-cause ESRD, African Americans were at significantly increased risk at age 18 to 30 years (adjusted HR, 1.17; 95% CI, 1.11-1.22). LIMITATIONS: We used zip code-based median household income as a surrogate for patient income. Residual socioeconomic confounders may exist. CONCLUSIONS: African Americans are at significantly increased risk of death compared with non-African Americans with LN-caused ESRD at age 18 to 40 years, a racial disparity risk that is 10 years longer than that in the general ESRD population. Accounting for area-level median household income and transplantation significantly attenuated the disparity in mortality of African American versus non-African American patients with LN-caused ESRD.

Cost-utility analysis of sodium polystyrene sulfonate vs. potential alternatives for chronic hyperkalemia.

PURPOSE: Hyperkalemia during renin-angiotensin-aldosterone system inhibition (RAAS-I) may prevent optimum dosing. Treatment options include sodium polystyrene sulfonate potassium binding resins, but safety and efficacy concerns exist, including associated colonic necrosis (CN). Alternative agents have been studied, but cost-utility has not been estimated. METHODS: We performed a cost-utility analysis of outpatients ≥ 18 years of age receiving chronic RAAS-I, with a history of hyperkalemia or chronic kidney disease, prescribed either sodium polystyrene sulfonate or a theoretical "drug X" binding resin for chronic hyperkalemia. Data were obtained from existing literature. We used a decision analytic model with Monte Carlo probabilistic sensitivity analyses, from a health care payer perspective and a 12-month time horizon. Costs were measured in US dollars. Effectiveness was measured in quality-adjusted life-years (QALYs), and incremental cost-effectiveness ratios (ICERs). RESULTS: Drug X could cost no more than $ 10.77 per daily dose to be cost-effective, at a willingness-to- pay (WTP) threshold of $ 50,000/QALY. At $ 40.00 per daily dose, drug X achieved an incremental cost effectiveness ratio of $26,088,369.00 per QALY gained. One-way sensitivity analysis showed sodium polystyrene sulfonate to be the cost-effective option for CN incidences ≤ 19.9%. Limitations include incomplete information on outpatient outcomes and lack of data directly comparing sodium polystyrene sulfonate to potential alternatives. CONCLUSIONS: Alternatives may not be cost-effective unless priced similarly to sodium polystyrene sulfonate. This analysis may guide decisions regarding adoption of alternative agents for chronic hyperkalemia control, and suggests that sodium polystyrene sulfonate be employed as an active control in clinical trials of these agents.

Association of prescription of oral sodium polystyrene sulfonate with sorbitol in an inpatient setting with colonic necrosis: a retrospective cohort study.

BACKGROUND: Colonic necrosis has been reported after sodium polystyrene sulfonate (SPS)/sorbitol use, but the incidence and relative risk (RR) are not established. STUDY DESIGN: Retrospective cohort study. SETTING & PARTICIPANTS: 123,391 adult inpatients at a tertiary medical center. PREDICTOR: Receipt of SPS prescriptions (exposed) or a prescription other than SPS (unexposed internal comparison group) between September 1, 2001, and October 31, 2010. OUTCOMES: The main outcome measure was tissue-confirmed diagnosis of colonic necrosis, considered SPS-associated if SPS was prescribed 30 or fewer days before tissue accession date. MEASUREMENTS: Demographics, serum chemistry test results, hospital location, and International Classification of Diseases, Ninth Revision diagnostic codes. RESULTS: SPS was prescribed to 2,194 inpatients. 82 inpatient colonic necrosis cases were identified. 3 received oral SPS (1 gram per 4 milliliters of 33% sorbitol) 30 or fewer days before the colonic necrosis accession date (3.7% of inpatient colonic necrosis cases). The data were linked with 123,391 individuals who received inpatient prescriptions between the same dates. Colonic necrosis incidence was 0.14% (95% CI, 0.03%-0.40%) in those prescribed SPS versus 0.07% (95% CI, 0.05-0.08%) in those not prescribed SPS (RR, 2.10; 95% CI, 0.68-6.48; P = 0.2). The number needed to harm was 1,395 (95% CI, 298-5,100). Subgroup analysis (age >65 years; estimated glomerular filtration rate, <30 mL/min/1.73 m(2), intensive care unit admission, or surgical ward status) did not show significant associations. Sample-size analysis indicated that 4,974 SPS-treated individuals older than 65 years and a comparison group 10 times larger would be required for rigorous multivariate analysis of SPS-associated colonic necrosis risk. LIMITATIONS: Individuals with colonic necrosis admitted to non-Department of Defense hospitals would not have been ascertained. Only individuals who had colonic biopsy or surgical tissue submitted for pathologic review could be ascertained as having colonic necrosis. CONCLUSIONS: SPS-associated colonic necrosis is rare, and inpatient SPS/sorbitol prescription was not associated significantly with an increased RR of colonic necrosis in this retrospective cohort analysis. Multivariate analysis would require retrospective clinical cohorts from larger or more than one hospital system(s).

Clinical and lung-function variables associated with vocal cord dysfunction.

BACKGROUND: Vocal cord dysfunction (VCD) is difficult to diagnose. Laryngoscopy while the patient is symptomatic is the accepted standard method to establish a diagnosis of VCD, but patient characteristics and spirometry values are thought to be useful for predicting VCD. We sought to identify clinical and spirometric variables that suggest VCD. METHODS: We performed 2 parallel studies. First, 3 staff pulmonologists (who were blinded to the laryngoscopy results), scored 3 flow-volume loops from each PFT session on the likelihood that the inspiratory curve indicated VCD. We also performed a cross-sectional study of clinical characteristics and spirometric data from all patients who underwent laryngoscopy for any indication, including suspected VCD, over a 3-year period. We compared the laryngoscopy findings to the clinical characteristics, spirometry results, and the pulmonologists' assessments of the flow-volume loops. We used multivariate logistic regression to identify independent predictors of VCD. RESULTS: The pulmonologists agreed about which flow-volume loops predicted VCD (quadratic kappa range 0.55-0.76), but those ratings were not predictive of laryngoscopic diagnosis of VCD. During the study period, 226 patients underwent laryngoscopy. One hundred (44%) were diagnosed with VCD. Independent predictors of VCD included female sex (odds ratio 2.72, 95% confidence interval 1.55-4.75) and obesity (body mass index > 30 kg/m(2)) (odds ratio 2.06, 95% confidence interval 1.12-3.80). With spirometric data from the effort that had the best forced-vital-capacity, multivariate analysis found the ratio of the forced inspiratory flow at 25% of the inspired volume to forced inspiratory flow at 75% of the inspired volume (FIF(25%/75%)) predictive of VCD (odds ratio 1.97, 95% confidence interval 1.12-3.44). The diagnostic performance of these characteristics was poor; the area under the receiver-operating-characteristic curve was 0.68. With the spirometric data from the effort that had the subjectively determined best inspiratory curve, and after controlling for the reproducibility of the inspiratory curves, multivariate analysis found none of the spirometric variables predictive of VCD. CONCLUSIONS: VCD remains difficult to predict with spirometry or flow-volume loops. If VCD is suspected, normal flow-volume loop patterns should not influence the decision to perform laryngoscopy.