Cataract Surgery in the Medicare Merit-Based Incentive Payment System: Episode-Based Cost Measure Development and Evaluation.

Objective: To characterize the development and performance of a cataract surgery episode-based cost measure for the Medicare Quality Payment Program. Design: Claims-based analysis. Participants: Medicare clinicians with cataract surgery claims between June 1, 2016, and May 31, 2017. Methods: We limited the analysis to claims with procedure code 66984 (routine cataract surgery), excluding cases with relevant ocular comorbidities. We divided episodes into subgroups by surgery location (Ambulatory Surgery Center [ASC] or Hospital Outpatient Department [HOPD]) and laterality (bilateral when surgeries were within 30 days apart). For the episode-based cost measure, we calculated costs occurring between 60 days before surgery and 90 days after surgery, limited to services identified by an expert committee as related to cataract surgery and under the influence of the cataract surgeon. We attributed costs to the clinician submitting the cataract surgery claim, categorized costs into clinical themes, and calculated episode cost distribution, reliability in detecting clinician-dependent cost variation, and costs with versus without complications. We compared episode-based cost scores with hypothetical "nonselective" cost scores (total Medicare beneficiary costs between 60 days before surgery and 90 days after surgery). Main Outcome Measures: Episode costs with and without complications, clinician-dependent variation (proportion of total cost variance), and proportion of costs from cataract surgery-related clinical themes. Results: We identified 583 356 cataract surgery episodes attributed to 10 790 clinicians and 8189 with ≥ 10 episodes during the measurement period. Most surgeries were performed in an ASC (71%) and unilateral (66%). The mean episode cost was $2876. The HOPD surgeries had higher costs; geography and episodes per clinician did not substantially affect costs. The proportion of cost variation from clinician-dependent factors was higher in episode-based compared with nonselective cost measures (94% vs. 39%), and cataract surgery-related clinical themes represented a higher proportion of total costs for episode-based measures. Episodes with complications had higher costs than episodes without complications ($3738 vs. $2276). Conclusions: The cataract surgery episode-based cost measure performs better than a comparable nonselective measure based on cost distribution, clinician-dependent variance, association with cataract surgery-related clinical themes, and quality alignment (higher costs in episodes with complications). Cost measure maintenance and refinement will be important to maintain clinical validity and reliability. Financial Disclosures: Proprietary or commercial disclosure may be found after the references.

Assessment of cellular responses in three-dimensional cell cultures through chemical exchange saturation transfer and 1 H MRS.

The article from this special issue was previously published in NMR In Biomedicine , Volume 35, Issue 9, 2022. For completeness we are including the title page of the article below. The full text of the article can be read in Issue 35:9 on Wiley Online Library: https://doi.org/10.1002/nbm.4757.

Association Between Preoperative Hemodialysis Timing and Postoperative Mortality in Patients With End-stage Kidney Disease.

Importance: For patients with end-stage kidney disease treated with hemodialysis, the optimal timing of hemodialysis prior to elective surgical procedures is unknown. Objective: To assess whether a longer interval between hemodialysis and subsequent surgery is associated with higher postoperative mortality in patients with end-stage kidney disease treated with hemodialysis. Design, Setting, and Participants: Retrospective cohort study of 1 147 846 procedures among 346 828 Medicare beneficiaries with end-stage kidney disease treated with hemodialysis who underwent surgical procedures between January 1, 2011, and September 30, 2018. Follow-up ended on December 31, 2018. Exposures: One-, two-, or three-day intervals between the most recent hemodialysis treatment and the surgical procedure. Hemodialysis on the day of the surgical procedure vs no hemodialysis on the day of the surgical procedure. Main Outcomes and Measures: The primary outcome was 90-day postoperative mortality. The relationship between the dialysis-to-procedure interval and the primary outcome was modeled using a Cox proportional hazards model. Results: Of the 1 147 846 surgical procedures among 346 828 patients (median age, 65 years [IQR, 56-73 years]; 495 126 procedures [43.1%] in female patients), 750 163 (65.4%) were performed when the last hemodialysis session occurred 1 day prior to surgery, 285 939 (24.9%) when the last hemodialysis session occurred 2 days prior to surgery, and 111 744 (9.7%) when the last hemodialysis session occurred 3 days prior to surgery. Hemodialysis was also performed on the day of surgery for 193 277 procedures (16.8%). Ninety-day postoperative mortality occurred after 34 944 procedures (3.0%). Longer intervals between the last hemodialysis session and surgery were significantly associated with higher risk of 90-day mortality in a dose-dependent manner (2 days vs 1 day: absolute risk, 4.7% vs 4.2%, absolute risk difference, 0.6% [95% CI, 0.4% to 0.8%], adjusted hazard ratio [HR], 1.14 [95% CI, 1.10 to 1.18]; 3 days vs 1 day: absolute risk, 5.2% vs 4.2%, absolute risk difference, 1.0% [95% CI, 0.8% to 1.2%], adjusted HR, 1.25 [95% CI, 1.19 to 1.31]; and 3 days vs 2 days: absolute risk, 5.2% vs 4.7%, absolute risk difference, 0.4% [95% CI, 0.2% to 0.6%], adjusted HR, 1.09 [95% CI, 1.04 to 1.13]). Undergoing hemodialysis on the same day as surgery was associated with a significantly lower hazard of mortality vs no same-day hemodialysis (absolute risk, 4.0% for same-day hemodialysis vs 4.5% for no same-day hemodialysis; absolute risk difference, -0.5% [95% CI, -0.7% to -0.3%]; adjusted HR, 0.88 [95% CI, 0.84-0.91]). In the analyses that evaluated the interaction between the hemodialysis-to-procedure interval and same-day hemodialysis, undergoing hemodialysis on the day of the procedure significantly attenuated the risk associated with a longer hemodialysis-to-procedure interval (P<.001 for interaction). Conclusions and Relevance: Among Medicare beneficiaries with end-stage kidney disease, longer intervals between hemodialysis and surgery were significantly associated with higher risk of postoperative mortality, mainly among those who did not receive hemodialysis on the day of surgery. However, the magnitude of the absolute risk differences was small, and the findings are susceptible to residual confounding.

Association Between Nephrologist Ownership of Dialysis Facilities and Clinical Outcomes.

Importance: Ownership of US dialysis facilities presents a financial conflict of interest for nephrologists, who may change their clinical practice to improve facility profitability. Objective: To investigate the association between nephrologist ownership of freestanding dialysis facilities and clinical outcomes. Design, Setting, and Participants: This cross-sectional study was conducted using US Renal Data System data linked to a data set of freestanding nonpediatric dialysis facility owners. Participants were a sample of all adults with fee-for-service Medicare receiving dialysis for end-stage kidney disease from January 2017 to November 2017 at included facilities. Data were analyzed from April 2020 through August 2022. Exposures: Outcomes associated with nephrologist ownership were assessed using a difference-in-differences analysis comparing the difference in outcomes between patients treated by nephrologist owners and patients treated by nonowners within facilities owned by nephrologists after accounting for differences in patient outcomes between nephrologist owners and nonowners in other facilities. Main Outcomes and Measures: Outcomes plausibly associated with nephrologist ownership were evaluated: (1) treatment volumes (missed treatments and transplant waitlist status); (2) erythropoietin-stimulating agent (ESA) use and related outcomes (anemia, defined as hemoglobin level <10 g/dL, and blood transfusions), (3) quality metrics (mortality, hospitalizations, 30-day readmissions, hemodialysis adequacy, arteriovenous fistula use, and hemodialysis catheter use for ≥3 months), and (4) home dialysis use. Results: A cohort of 251 651 patients (median [IQR] age, 66 [46-85] years; 112 054 [44.5%] women; 9765 Asian [3.9%], 86 837 Black [34.5%], and 148 617 White [59.1%]; 38 938 Hispanic [15.5%]) receiving dialysis for end-stage kidney disease were included. Patient treatment by nephrologist owners at their owned facilities was associated with a 2.4 percentage point (95% CI, 1.1-3.8 percentage points) higher probability of home dialysis, a 2.2 percentage point (95% CI, 3.6-0.7 percentage points) lower probability of receiving an ESA, and no significant difference in anemia or blood transfusions. Patient treatment by nephrologist owners at their owned facilities was not associated with differences in missed treatments, transplant waitlisting, mortality, hospitalizations, 30-day readmissions, hemodialysis adequacy, or fistula or long-term dialysis catheter use. Conclusions and Relevance: This cross-sectional cohort study found that nephrologist ownership was associated with increased home dialysis use, decreased ESA use, and no change in anemia or blood transfusions.

Medicare Advantage Plans Pay Large Markups To Consolidated Dialysis Organizations.

The 21st Century Cures Act of 2016 lifted regulations prohibiting Medicare Advantage (MA) enrollment after patients initiate dialysis, starting in 2021, and early reports indicate increased MA enrollment among such patients. Large shifts into Medicare Advantage could disrupt the market because the consolidated dialysis industry can negotiate payment from MA plans that is higher than that for fee-for-service Medicare. For three large insurers representing 48 percent of the 2016-17 MA market, we found that MA plans paid 27 percent more than fee-for-service Medicare. Larger dialysis center chains commanded higher markups. Virtually all facilities of the two largest chains were in network, suggesting that they leverage their market power into all-or-nothing negotiations with plans. Policy makers should consider regulations that limit market consolidation among dialysis providers, as well as their ability to exercise that power in the MA market.

Assessment of cellular responses in three-dimensional cell cultures through chemical exchange saturation transfer and 1 H MRS.

Metabolic responses to physiological changes have been detected using chemical exchange saturation transfer (CEST) imaging in clinical settings. Similarly to other MRI techniques, the CEST technique was based originally on phantoms from buffer solutions and was then further developed through animal experiments. However, CEST imaging can capture certain dynamics of metabolism that solution phantoms cannot model. Cell culture phantoms can fill the gap between buffer phantoms and animal models. In this study, we used 1 H NMR and CEST in a B0 field of 9.4 T to investigate HEK293T cells from two-dimensional (2D) cultures, three-dimensional (3D) cultures, and 3D cultures seeded with cell spheroids. Two CEST dips were observed: the magnitude of the amine dip at 2.8 ppm increased during the incubation period, whereas the hydroxyl dip at 1.2 ppm remained approximately the same or modestly increased. We also observed a CEST dip at 2.8 ppm from the 2D culture responding dramatically to doxorubicin treatment. By cross-validating with pH values and the concentrations of amine and hydroxyl protons extracted through 1 H NMR, we observed that they did not correspond to an increase in the amine pool. We believe that the denaturation or degradation of proteins from the fetal bovine serum increased the size of the amine pool. Although 3D culture conditions can be further improved, our study suggests that 3D cultures have the potential to bridge studies of solution phantoms and those on animals.

Patient Frailty and Functional Use of Hemodialysis Vascular Access: A Retrospective Study of the US Renal Data System.

RATIONALE & OBJECTIVE: Despite the high prevalence of frailty among dialysis patients, it is unknown whether frailty is associated with dialysis vascular access failure. This study examined the association between frailty and functional use of vascular access. STUDY DESIGN: Retrospective observational study. SETTING & PARTICIPANTS: Patients who initiated hemodialysis through a tunneled catheter in the US Renal Data System database from 2012 through 2017 and underwent subsequent creation of an arteriovenous fistula or graft. PREDICTORS: The "claims-based frailty indicator" (CFI) was calculated using a validated claims-based disability status model anchored to a well-described frailty phenotype. OUTCOMES: Time to functional use for fistulas and grafts defined as the time from initiation of hemodialysis to treatments using the index vascular access with 2 needles. ANALYTICAL APPROACH: Fine and Gray competing risk models separately examining fistula and graft outcomes. Patient survival was modeled for the entire cohort using Cox proportional hazards regression. RESULTS: A total of 41,471 patients met inclusion criteria, including 33,212 who underwent fistula creation and 8,259 who underwent graft placement. Higher CFI quartiles were associated with a greater rate of mortality. Patients in the highest CFI quartile had more than 2 times the rate of mortality compared with patients in the lowest CFI quartile (hazard ratio [HR], 2.49 [95% CI, 2.41-2.58]). In multivariable analyses, the highest CFI quartile was significantly associated with longer time to functional use of fistulas (HR, 0.65 [95% CI, 0.62-0.69]) and grafts (HR, 0.88 [95% CI, 0.79-0.98]). LIMITATIONS: Generalizability may be limited by the requirement of 12 months of Medicare claims availability before initiation of dialysis. There were no data on patient anatomic characteristics or surgeon characteristics and limited patient-specific sociodemographic data. CONCLUSIONS: Higher degrees of frailty are associated with longer times to vascular access functional use. Frailty may be useful for informing clinical decision-making regarding choice of vascular access.

Challenging Assumptions of Outcomes and Costs Comparing Peritoneal and Hemodialysis.

OBJECTIVES: Policy makers have suggested increasing peritoneal dialysis (PD) would improve end-stage kidney disease (ESKD) outcomes and reduce Medicare spending compared with hemodialysis (HD). We compared mortality, hospitalizations, and Medicare spending between PD and HD among uninsured adults with incident ESKD. METHODS: Using an instrumental variable design, we exploited a natural experiment encouraging PD among the uninsured. Uninsured patients usually receive Medicare at dialysis month 4. For those initiating PD, Medicare covers the first 3 dialysis months, including predialysis services in the calendar month when dialysis started. Starting dialysis later in a calendar month increases predialysis coverage that is essential for PD catheter placements. The policy encourages PD incrementally when ESKD develops later in the month. Dialysis start day appears to be unrelated to patient characteristics and effectively "randomizes patients" to dialysis modality, mitigating selection bias. RESULTS: Starting dialysis later in the month was associated with an increased PD uptake: every week later in the month was associated with an absolute increase of 0.8% (95% confidence interval [CI] 0.6%-0.9%) at dialysis day 1 and 0.5% (95% CI 0.3%-0.7%) at dialysis month 12. We observed no significant absolute difference between PD and HD for 12-month mortality (-0.9%, 95% CI -3.3% to 0.8%), hospitalizations during months 7 to 12 (-0.05, 95% CI -0.20 to 0.07), and Medicare spending during months 7 to 12 (-$702, 95% CI -$4004 to $2909). CONCLUSIONS: In an instrumental variable analysis, PD did not result in improved outcomes or lower costs than HD.

Development of the Elective Outpatient Percutaneous Coronary Intervention Episode-Based Cost Measure.

BACKGROUND: The Merit-Based Incentive Payment System adjusts clinician payments based on a performance score that includes cost measures. With the Centers for Medicare & Medicaid Services, we developed a novel cost measure that compared interventional cardiologists on a targeted set of costs related to elective percutaneous coronary intervention (PCI). We describe the measure and compare it to a hypothetical version including all expenditures post-PCI. METHODS: Measure development was guided by 39 clinician experts. They identified services within 30 days of PCI that could be potentially affected by the interventional cardiologist. Expenditures for these PCI-related services were included as measure costs in a process termed service assignment. We used 1 year of Medicare claims to calculate clinician scores using the final measure that included only PCI-related costs (with service assignment) and a hypothetical version that included all costs post-PCI (without service assignment). We calculated reliability for both measures. This marker of precision breaks measure variance into signal (difference between clinicians) versus noise (difference between PCI episodes for a clinician). We also determined the change in clinician performance quintile between measures. RESULTS: We identified 100 992 elective outpatient PCI episodes from May 2, 2016, to May 1, 2017. Total Medicare expenditures within 30 days of PCI averaged $13 234. After excluding costs unrelated to PCI, average cost was $10 966. For individual clinicians, mean reliability for the hypothetical measure without service assignment was 0.36. After service assignment, final measure reliability increased to 0.53. When evaluated as clinician groups, reliability increased from 0.43 to 0.73 following service assignment. Approximately 66% (2340 of 3527) of clinicians were reclassified into a different performance quintile after excluding unrelated costs. CONCLUSIONS: The elective outpatient PCI cost measure had increased precision and reclassified clinician performance relative to a hypothetical version that included total expenditures.

Policy and Pandemic: The Changing Practice of Nephrology During the Coronavirus Disease-2019 Outbreak.

The coronavirus (coronavirus disease-2019) pandemic has changed care delivery for patients with end-stage kidney disease. We explore the US healthcare system as it pertains to dialysis care, including existing policies, modifications implemented in response to the coronavirus disease-2019 crisis, and possible next steps for policy makers and nephrologists. This includes policies related to resource management, use of telemedicine, prioritization of dialysis access procedures, expansion of home dialysis modalities, administrative duties, and quality assessment. The government has already established policies that have instated some flexibilities to help providers focus their response to the crisis. However, future policy during and after the coronavirus disease-2019 pandemic can bolster our ability to optimize care for patients with end-stage kidney disease. Key themes in this perspective are the importance of policy flexibility, clear strategies for emergency preparedness, and robust health systems that maximize accessibility and patient autonomy.

Early Delays in Insurance Coverage and Long-term Use of Home-based Peritoneal Dialysis.

BACKGROUND: Uninsured patients with end-stage renal disease face barriers to peritoneal dialysis (PD), a type of home dialysis that is associated with improved quality of life and reduced Medicare costs. Although uninsured patients using PD at dialysis start receive retroactive Medicare coverage for required predialysis services, coverage only applies for the calendar month of dialysis start. Thus, initiating dialysis later in the month yields longer retroactive coverage. OBJECTIVES: To examine whether differences in retroactive Medicare were associated with decreased long-term PD use. RESEARCH DESIGN: We exploited the dialysis start date using a regression discontinuity design on a national cohort from the US Renal Data System. SUBJECTS: 36,256 uninsured adults starting dialysis between January 1, 2006 and December 31, 2014. MEASURES: PD use at dialysis days 1, 90, 180, and 360. RESULTS: Starting dialysis on the first versus last day of the calendar month was associated with an absolute decrease in PD use of 2.7% [95% confidence interval (CI), 1.5%-3.9%], or a relative decrease of 20% (95% CI, 12%-27%) at dialysis day 360. The absolute decrease was 5.5% (95% CI, 3.5%-7.2%) after Medicare established provider incentives for PD in 2011 and 7.2% (95% CI, 2.5%-11.9%) after Medicaid expansion in 2014. Patients were unlikely to switch from hemodialysis to PD after the first month of dialysis (probability of 6.9% in month 1, 1.5% in month 2, and 0.9% in month 4). CONCLUSIONS: Extending retroactive coverage for preparatory dialysis services could increase PD use and reduce overall Medicare spending in the uninsured.