Changes in Hospital Adverse Events and Patient Outcomes Associated With Private Equity Acquisition.

Importance: The effects of private equity acquisitions of US hospitals on the clinical quality of inpatient care and patient outcomes remain largely unknown. Objective: To examine changes in hospital-acquired adverse events and hospitalization outcomes associated with private equity acquisitions of US hospitals. Design, Setting, and Participants: Data from 100% Medicare Part A claims for 662 095 hospitalizations at 51 private equity-acquired hospitals were compared with data for 4 160 720 hospitalizations at 259 matched control hospitals (not acquired by private equity) for hospital stays between 2009 and 2019. An event study, difference-in-differences design was used to assess hospitalizations from 3 years before to 3 years after private equity acquisition using a linear model that was adjusted for patient and hospital attributes. Main Outcomes and Measures: Hospital-acquired adverse events (synonymous with hospital-acquired conditions; the individual conditions were defined by the US Centers for Medicare & Medicaid Services as falls, infections, and other adverse events), patient mix, and hospitalization outcomes (including mortality, discharge disposition, length of stay, and readmissions). Results: Hospital-acquired adverse events (or conditions) were observed within 10 091 hospitalizations. After private equity acquisition, Medicare beneficiaries admitted to private equity hospitals experienced a 25.4% increase in hospital-acquired conditions compared with those treated at control hospitals (4.6 [95% CI, 2.0-7.2] additional hospital-acquired conditions per 10 000 hospitalizations, P = .004). This increase in hospital-acquired conditions was driven by a 27.3% increase in falls (P = .02) and a 37.7% increase in central line-associated bloodstream infections (P = .04) at private equity hospitals, despite placing 16.2% fewer central lines. Surgical site infections doubled from 10.8 to 21.6 per 10 000 hospitalizations at private equity hospitals despite an 8.1% reduction in surgical volume; meanwhile, such infections decreased at control hospitals, though statistical precision of the between-group comparison was limited by the smaller sample size of surgical hospitalizations. Compared with Medicare beneficiaries treated at control hospitals, those treated at private equity hospitals were modestly younger, less likely to be dually eligible for Medicare and Medicaid, and more often transferred to other acute care hospitals after shorter lengths of stay. In-hospital mortality (n = 162 652 in the population or 3.4% on average) decreased slightly at private equity hospitals compared with the control hospitals; there was no differential change in mortality by 30 days after hospital discharge. Conclusions and Relevance: Private equity acquisition was associated with increased hospital-acquired adverse events, including falls and central line-associated bloodstream infections, along with a larger but less statistically precise increase in surgical site infections. Shifts in patient mix toward younger and fewer dually eligible beneficiaries admitted and increased transfers to other hospitals may explain the small decrease in in-hospital mortality at private equity hospitals relative to the control hospitals, which was no longer evident 30 days after discharge. These findings heighten concerns about the implications of private equity on health care delivery.

Prescription Drug Spending in Fee-for-Service Medicare, 2008-2019.

Importance: Prescription drug spending is a topic of increased interest to the public and policymakers. However, prior assessments have been limited by focusing on retail spending (Part D-covered drugs), omitting clinician-administered (Part B-covered) drug spending, or focusing on all fee-for-service Medicare beneficiaries, regardless of their enrollment into prescription drug coverage. Objective: To estimate the proportion of health care spending contributed by prescription drugs and to assess spending for retail and clinician-administered prescriptions. Design, Setting, and Participants: Descriptive, serial, cross-sectional analysis of a 20% random sample of fee-for-service Medicare beneficiaries in the United States from 2008 to 2019 who were continuously enrolled in Parts A (hospital), B (medical), and D (prescription drug) benefits, and not in Medicare Advantage. Exposure: Calendar year. Main Outcomes and Measures: Net spending on retail (Part D-covered) and clinician-administered (Part B-covered) prescription drugs; prescription drug spending (spending on Part B-covered and Part D-covered drugs) as a percentage of total per-capita health care spending. Measures were adjusted for inflation and for postsale rebates (for Part D-covered drugs). Results: There were 3 201 284 beneficiaries enrolled in Parts A, B, and D in 2008 and 4 502 718 in 2019. In 2019, beneficiaries had a mean (SD) age of 71.7 (12.0) years, documented sex was female for 57.7%, and 69.5% had no low-income subsidies. Total per-capita spending was $16 345 in 2008 and $20 117 in 2019. Comparing 2008 with 2019, per-capita Part A spending was $7106 (95% CI, $7084-$7128) vs $7120 (95% CI, $7098-$7141), Part B drug spending was $720 (95% CI, $713-$728) vs $1641 (95% CI, $1629-$1653), Part B nondrug spending was $5113 (95% CI, $5105-$5122) vs $6702 (95% CI, $6692-$6712), and Part D net spending was $3122 (95% CI, $3117-$3127) vs $3477 (95% CI, $3466-$3489). The proportion of total annual spending attributed to prescription drugs increased from 24.0% in 2008 to 27.2% in 2019, net of estimated rebates and discounts. Conclusions and Relevance: In 2019, spending on prescription drugs represented approximately 27% of total spending among fee-for-service Medicare beneficiaries enrolled in Part D, even after accounting for postsale rebates.

Higher Surgeon Procedure Volume Is Associated with Improved Hemodialysis Vascular Access Outcomes.

The objective of this study was to examine the association between surgeon characteristics, procedural volume, and short-term outcomes of hemodialysis vascular access. A retrospective cohort study was performed using Medicare Part A and B data from 2007 through 2014 merged with American Medical Association Physician Masterfile surgeon data. A total of 29,034 procedures met the inclusion criteria: 22,541 (78%) arteriovenous fistula (AVF) and 6,493 (22%) arteriovenous graft (AVG). Of these, 13,110 (45.2%) were performed by vascular surgeons, 9,398 (32.3%) by general surgeons, 2,313 (8%) by thoracic surgeons, 1,517 (5.2%) by other specialties, and 2,696 (9.3%) were unknown. Every 10-year increase in years in practice was associated with a 6.9 per cent decrease in the odds of creating AVF versus AVG (P = 0.02). Surgeon characteristics were not associated with the likelihood of vascular access failure. Every 10-procedure increase in cumulative procedure volume was associated with a 5 per cent decrease in the odds of vascular access failure (P = 0.007). There was no association of provider characteristics or procedure volume with survival free of repeat AVF/AVG or TC placement at 12 months. A significant portion of the variability in likelihood of creating AVF versus AVG is attributable to the provider-level variation. Increase in procedure volume is associated with decreased odds of vascular access failure.

Medication adherence as a measure of the quality of care provided by physicians.

OBJECTIVES: To assess the extent to which medication adherence in congestive heart failure (CHF) and diabetes may serve as a measure of physician-level quality. STUDY DESIGN: A retrospective analysis of Medicare data from 2007 to 2009, including parts A (inpatient), B (outpatient), and D (pharmacy). METHODS: For each disease, we assessed the correlation between medication adherence and health outcomes at the physician level. We controlled for selection bias by first regressing patient-level outcomes on a set of covariates including comorbid conditions, demographic attributes, and physician fixed effects. We then classified physicians into 3 levels of average patient medication adherence-low, medium, and high-and compared health outcomes across these groups. RESULTS: There is a clear relationship between average medication adherence and patient health outcomes as measured at the physician level. Within the diabetes sample, among physicians with high average adherence and controlling for patient characteristics, 26.3 per 1000 patients had uncontrolled diabetes compared with 45.9 per 1000 patients among physicians with low average adherence. Within the CHF sample, also controlling for patient characteristics, the average rate of CHF emergency care usage among patients seen by physicians with low average adherence was 16.3% compared with 13.5% for doctors with high average adherence. CONCLUSIONS: This study's results establish a physician-level correlation between improved medication adherence and improved health outcomes in the Medicare population. Our findings suggest that medication adherence could be a useful measure of physician quality, at least for chronic conditions for which prescription medications are an important component of treatment.

Admission diagnoses among patients with heart failure: Variation by ACO performance on a measure of risk-standardized acute admission rates.

BACKGROUND: A key quality metric for Accountable Care Organizations (ACOs) is the rate of hospitalization among patients with heart failure (HF). Among this patient population, non-HF-related hospitalizations account for a substantial proportion of admissions. Understanding the types of admissions and the distribution of admission types across ACOs of varying performance may provide important insights for lowering admission rates. METHODS: We examined admission diagnoses among 220 Medicare Shared Savings Program ACOs in 2013. ACOs were stratified into quartiles by their performance on a measure of unplanned risk-standardized acute admission rates (RSAARs) among patients with HF. Using a previously validated algorithm, we categorized admissions by principal discharge diagnosis into: HF, cardiovascular/non-HF, and noncardiovascular. We compared the mean admission rates by admission type as well as the proportion of admission types across RSAAR quartiles (Q1-Q4). RESULTS: Among 220 ACOs caring for 227,356 patients with HF, the median (IQR) RSAARs per 100 person-years ranged from 64.5 (61.7-67.7) in Q1 (best performers) to 94.0 (90.1-99.9) in Q4 (worst performers). The mean admission rates by admission types for ACOs in Q1 compared with Q4 were as follows: HF admissions: 9.8 (2.2) vs 14.6 (2.8) per 100 person years (P < .0001); cardiovascular/non-HF admissions: 11.1 (1.6) vs 15.9 (2.6) per 100 person-years (P < .0001); and noncardiovascular admissions: 42.7 (5.4) vs 69.6 (11.3) per 100 person-years (P < .0001). The proportion of admission due to HF, cardiovascular/non-HF, and noncardiovascular conditions was 15.4%, 17.5%, and 67.1% in Q1 compared with 14.6%, 15.9%, and 69.4% in Q4 (P < .007). CONCLUSIONS: Although ACOs with the best performance on a measure of all-cause admission rates among people with HF tended to have fewer admissions for HF, cardiovascular/non-HF, and noncardiovascular conditions compared with ACOs with the worst performance (highest admission rates), the largest difference in admission rates were for noncardiovascular admission types. Across all ACOs, two-thirds of admissions of patients with HF were for noncardiovascular causes. These findings suggest that comprehensive approaches are needed to reduce the diverse admission types for which HF patients are at risk.

Empirical-Based Typology of Health Care Utilization by Medicare Eligible Veterans.

OBJECTIVE: Up to 70 percent of patients who receive care through Veterans Health Administration (VHA) facilities also receive care from non-VA providers. Using applied classification techniques, this study sought to improve understanding of how elderly VA patients use VA services and complementary use of non-VA care. METHODS: The study included 1,721,900 veterans age 65 and older who were enrolled in VA and Medicare during 2013 with at least one VA encounter during 2013. Outpatient and inpatient encounters and medications received in VA were classified, and mutually exclusive patient subsets distinguished by patterns of VA service use were derived empirically using latent class analysis (LCA). Patient characteristics and complementary use of non-VA care were compared by patient subset. RESULTS: Five patterns of VA service use were identified that were distinguished by quantity of VA medical and specialty services, medication complexity, and mental health services. Low VA Medical users tend to be healthier and rely on non-VA services, while High VA users have multiple high cost illnesses and concentrate their care in the VA. CONCLUSIONS: VA patients distinguished by patterns of VA service use differ in illness burden and the use of non-VA services. This information may be useful for framing efforts to optimize access to care and care coordination for elderly VA patients.

Octogenarians' post-acute care use after cardiac valve surgery and recovery: clinical implications.

Octogenarians receiving cardiac valve surgery is increasing and recovery is challenging. Post-acute care (PAC) services assist with recovery, yet services provided in facilities do not provide adequate cardiac-focused care or long-term self-management support. The purpose of the paper was to report post-acute care discharge rates in octogenarians and propose clinical implications to improve PAC services. Using a 2003 Medicare Part A database, we studied post-acute care service use in octogenarians after cardiac valve surgery. We propose expansion of the Geriatric Cardiac Care model to include broader clinical therapy dynamics. The sample (n = 10,062) included patients over 80 years discharged from acute care following valve surgery. Post-acute care services were used by 68% of octagarians following cardiac valve surgery (1% intermediate rehabilitation, 35% skilled nursing facility, 32% home health). The large percentage of octagarians using PAC point to the importance of integrating geriatric cardiac care into post-acute services to optimize recovery outcomes.

The Role of Medicare's Inpatient Cost-Sharing in Medicaid Entry.

OBJECTIVE: To isolate the effect of greater inpatient cost-sharing on Medicaid entry among Medicare beneficiaries. DATA SOURCES: Medicare administrative data (years 2007-2010) were linked to nursing home assessments and area-level socioeconomic indicators. STUDY DESIGN: Medicare beneficiaries who are readmitted to a hospital must pay an additional deductible ($1,100 in 2010) if their readmission occurs more than 59 days following discharge. In a regression discontinuity analysis, we take advantage of this Medicare benefit feature to test whether beneficiaries with greater cost-sharing have higher rates of Medicaid enrollment. DATA EXTRACTION METHODS: We identified 221,248 Medicare beneficiaries with an initial hospital stay and a readmission 53-59 days later (no deductible) or 60-66 days later (charged a deductible). PRINCIPAL FINDINGS: Among beneficiaries in low-socioeconomic areas with two hospitalizations, those readmitted 60-66 days after discharge were 21 percent more likely to join Medicaid compared with those readmitted 53-59 days following their initial hospitalization (absolute difference in adjusted risk of Medicaid entry: 3.7 percent vs. 3.1 percent, p = .01). CONCLUSIONS: Increasing Medicare cost-sharing requirements may promote Medicaid enrollment among low-income beneficiaries. Potential savings from an increased cost-sharing in the Medicare program may be offset by increased Medicaid participation.

Propensity scores with misclassified treatment assignment: a likelihood-based adjustment.

Propensity score methods are widely used in comparative effectiveness research using claims data. In this context, the inaccuracy of procedural or billing codes in claims data frequently misclassifies patients into treatment groups, that is, the treatment assignment ($T$) is often measured with error. In the context of a validation data where treatment assignment is accurate, we show that misclassification of treatment assignment can impact three distinct stages of a propensity score analysis: (i) propensity score estimation; (ii) propensity score implementation; and (iii) outcome analysis conducted conditional on the estimated propensity score and its implementation. We examine how the error in $T$ impacts each stage in the context of three common propensity score implementations: subclassification, matching, and inverse probability of treatment weighting (IPTW). Using validation data, we propose a two-step likelihood-based approach which fully adjusts for treatment misclassification bias under subclassification. This approach relies on two common measurement error-assumptions; non-differential measurement error and transportability of the measurement error model. We use simulation studies to assess the performance of the adjustment under subclassification, and also investigate the method's performance under matching or IPTW. We apply the methods to Medicare Part A hospital claims data to estimate the effect of resection versus biopsy on 1-year mortality among $10\,284$ Medicare beneficiaries diagnosed with brain tumors. The ICD9 billing codes from Medicare Part A inaccurately reflect surgical treatment, but SEER-Medicare validation data are available with more accurate information.

Damage caps and defensive medicine, revisited.

Does tort reform reduce defensive medicine and thus healthcare spending? Several (though not all) prior studies, using a difference-in-differences (DiD) approach, find lower Medicare spending for hospital care after states adopt caps on non-economic or total damages ("damage caps"), during the "second" reform wave of the mid-1980s. We re-examine this issue in several ways. We study the nine states that adopted caps during the "third reform wave," from 2002 to 2005. We find that damage caps have no significant impact on Medicare Part A spending, but predict roughly 4% higher Medicare Part B spending. We then revisit the 1980s caps, and find no evidence of a post-adoption drop (or rise) in spending for these caps.

Variation in Payment Rates under Medicare's Inpatient Prospective Payment System.

OBJECTIVE: To measure variation in payment rates under Medicare's Inpatient Prospective Payment System (IPPS) and identify the main payment adjustments that drive variation. DATA SOURCES/STUDY SETTING: Medicare cost reports for all Medicare-certified hospitals, 1987-2013, and Dartmouth Atlas geographic files. STUDY DESIGN: We measure the Medicare payment rate as a hospital's total acute inpatient Medicare Part A payment, divided by the standard IPPS payment for its geographic area. We assess variation using several measures, both within local markets and nationally. We perform a factor decomposition to identify the share of variation attributable to specific adjustments. We also describe the characteristics of hospitals receiving different payment rates and evaluate changes in the magnitude of the main adjustments over time. DATA COLLECTION/EXTRACTION METHODS: Data downloaded from the Centers for Medicare and Medicaid Services, the National Bureau of Economic Research, and the Dartmouth Atlas. PRINCIPAL FINDINGS: In 2013, Medicare paid for acute inpatient discharges at a rate 31 percent above the IPPS base. For the top 10 percent of discharges, the mean rate was double the IPPS base. Variations were driven by adjustments for medical education and care to low-income populations. The magnitude of variation has increased over time. CONCLUSIONS: Adjustments are a large and growing share of Medicare hospital payments, and they create significant variation in payment rates.

Cost Drivers After Surgical Management of Proximal Humerus Fractures in Medicare Patients.

OBJECTIVES: This comparative effectiveness study sought to determine the impact of complications, readmission, and procedure choice on in-hospital and total 90-day costs for surgical management of proximal humerus fractures. METHODS: Medicare claims data from the Upstate New York area (2008-2009) were evaluated. The study included all patients treated with open reduction and internal fixation (ORIF) or hemiarthroplasty for proximal humerus fracture identified by ICD-9 codes. The primary end points included in-hospital costs and total health care costs within 90 days after the index operation. Multivariable generalized linear models with negative binomial distributions and log link function were used for cost analysis. RESULTS: ORIF was performed in 52 cases and hemiarthroplasty in 57 cases, total n = 109. On univariate analysis, readmission increased in-hospital cost by $54,345 and total 90-day costs by $63,104, whereas complications increased in-hospital cost by $23,300 and total 90-day costs by $30,237. On multivariable analysis, ORIF was associated with 29% lower in-hospital cost compared with hemiarthroplasty [Odds Ratio 0.71; 95% Confidence Interval (CI), 0.54-0.92; P = 0.01], and readmission was associated with a 5.68-fold in-hospital cost increase (Odds Ratio 5.68; CI, 3.57-9.03; P < 0.0001). CONCLUSIONS: Complications and hospital readmission continue to drive cost upward underscoring the need for best practice. The acute inpatient period costs may be decreased with ORIF in appropriately selected patients with proximal humerus fractures in comparison with hemiarthroplasty. This study provides real world cost estimates with the cost implications of complications, readmissions, and procedure choice. LEVEL OF EVIDENCE: Economic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Comparative Risk of Anaphylactic Reactions Associated With Intravenous Iron Products.

IMPORTANCE: All intravenous (IV) iron products are associated with anaphylaxis, but the comparative safety of each product has not been well established. OBJECTIVE: To compare the risk of anaphylaxis among marketed IV iron products. DESIGN, SETTING, AND PARTICIPANTS: Retrospective new user cohort study of IV iron recipients (n = 688,183) enrolled in the US fee-for-service Medicare program from January 2003 to December 2013. Analyses involving ferumoxytol were limited to the period January 2010 to December 2013. EXPOSURES: Administrations of IV iron dextran, gluconate, sucrose, or ferumoxytol as reported in outpatient Medicare claims data. MAIN OUTCOMES AND MEASURES: Anaphylaxis was identified using a prespecified and validated algorithm defined with standard diagnosis and procedure codes and applied to both inpatient and outpatient Medicare claims. The absolute and relative risks of anaphylaxis were estimated, adjusting for imbalances among treatment groups. RESULTS: A total of 274 anaphylaxis cases were identified at first exposure, with an additional 170 incident anaphylaxis cases identified during subsequent IV iron administrations. The risk for anaphylaxis at first exposure was 68 per 100,000 persons for iron dextran (95% CI, 57.8-78.7 per 100,000) and 24 per 100,000 persons for all nondextran IV iron products combined (iron sucrose, gluconate, and ferumoxytol) (95% CI, 20.0-29.5 per 100,000) , with an adjusted odds ratio (OR) of 2.6 (95% CI, 2.0-3.3; P < .001). At first exposure, when compared with iron sucrose, the adjusted OR of anaphylaxis for iron dextran was 3.6 (95% CI, 2.4-5.4); for iron gluconate, 2.0 (95% CI 1.2, 3.5); and for ferumoxytol, 2.2 (95% CI, 1.1-4.3). The estimated cumulative anaphylaxis risk following total iron repletion of 1000 mg administered within a 12-week period was highest with iron dextran (82 per 100,000 persons, 95% CI, 70.5- 93.1) and lowest with iron sucrose (21 per 100,000 persons, 95% CI, 15.3- 26.4). CONCLUSIONS AND RELEVANCE: Among patients in the US Medicare nondialysis population with first exposure to IV iron, the risk of anaphylaxis was highest for iron dextran and lowest for iron sucrose.

Colorectal Cancer Identification Methods Among Kansas Medicare Beneficiaries, 2008-2010.

INTRODUCTION: Population-based data are limited on how often colorectal cancer (CRC) is identified through screening or surveillance in asymptomatic patients versus diagnostic workup for symptoms. We developed a process for assessing CRC identification methods among Medicare-linked CRC cases from a population-based cancer registry to assess identification methods (screening/surveillance or diagnostic) among Kansas Medicare beneficiaries. METHODS: New CRC cases diagnosed from 2008 through 2010 were identified from the Kansas Cancer Registry and matched to Medicare enrollment and claims files. CRC cases were classified as diagnostic-identified versus screening/surveillance-identified using a claims-based algorithm for determining CRC test indication. Factors associated with screening/surveillance-identified CRC were analyzed using logistic regression. RESULTS: Nineteen percent of CRC cases among Kansas Medicare beneficiaries were screening/surveillance-identified while 81% were diagnostic-identified. Younger age at diagnosis (65 to 74 years) was the only factor associated with having screening/surveillance-identified CRC in multivariable analysis. No association between rural/urban residence and identification method was noted. CONCLUSION: Combining administrative claims data with population-based registry records can offer novel insights into patterns of CRC test use and identification methods among people diagnosed with CRC. These techniques could also be extended to other screen-detectable cancers.

Review of MRI wrist examination since introduction of Medicare item number.

INTRODUCTION: The Australian Health Department provided extended rebatable requesting rights to general practitioners in 2012 for magnetic resonance imaging (MRI) examinations in patients less than 16 years of age for a small set of clinically appropriate indications. Included item numbers 63522 and 63523 'referral by a medical practitioner (excluding a specialist and consultant physician) for a scan of wrist following radiographic examination where scaphoid fracture is suspected'. The aim of this study is to evaluate MRI examinations of suspected scaphoid fractures in the paediatric population following the Medicare item number introduction. METHODS: Review of 60 consecutive MR wrist examinations requested by general practitioners and performed between 30 November 2012 and 16 July 2014 for a rebatable magnet in a private clinical setting. The indication for all studies was to exclude a clinically suspected fractured scaphoid following a normal radiograph. All patients were less than 16 years of age at time of examination. RESULTS: Sixty examinations were performed; 51 revealed pathology (85% of cases) with nine normal examinations (15%). Twenty-nine studies revealed one of more fractures involving the carpals, metacarpals or distal radius. In total, 41 fractures were identified on MRI examination with 29 carpal bone fractures, six distal radius fractures and six metacarpal fractures. CONCLUSIONS: The results highlight the sensitivity of MR wrist examination and its diagnostic benefit in clinically suspected paediatric scaphoid fractures. In addition, it reflects the prudent referral nature of general practitioners.

Total joint arthroplasty: trends in medicare reimbursement and implant prices.

Total joint arthroplasty (TJA) continues to be a popular target of cost control efforts. In order to provide a unique overview of financial trends facing TJA, we analyzed Medicare databases including 100% of beneficiaries, as well as industry surveys of implant list prices. Although there was a substantial increase in TJA utilization over the period 2000-2011 (+26.9%), growth has been stagnant since 2005. New coding schemes have made complicated cases more lucrative for hospitals (+2.5% to 6.5% per year), while reimbursements for uncomplicated cases have fallen (-0.7% to -0.6%). Physician reimbursements have declined on all case types (-2.5% to -2.1% per year), while list prices of orthopedic implants have risen (+4.8% to 5.5%). These trends should be kept in mind while contemplating future changes to TJA payment.

Association between outpatient visits following hospital discharge and readmissions among Medicare beneficiaries with atrial fibrillation and other chronic conditions.

Atrial fibrillation (AF) afflicts nearly 3 million people in the United States annually, the large majority of whom are Medicare beneficiaries with other chronic illnesses. Beneficiaries with multiple chronic conditions have high hospitalization and readmission rates but evidence on factors associated with readmissions is limited, and little is known about differences in rates between beneficiaries with and without AF. In a retrospective analysis of Medicare claims data, the relationship between outpatient visits within 14 days after hospital discharge and readmission was examined for beneficiaries with AF or other chronic conditions. About half of those beneficiaries with a hospitalization had an outpatient visit within 14 days of discharge. Readmission rates were 11% to 24% lower for beneficiaries with an outpatient visit than for those without one (P < .01). These findings suggest that follow-up care shortly after discharge may lower readmissions for patients with AF or other chronic conditions.

Regional variation in medicare imaging utilization and expenditures: 2007-2011 trends and comparison with other health services.

PURPOSE: A 2008 federal report expressed concern regarding substantial regional variation in imaging expenditures. The aims of this study were to evaluate trends in regional variation in Medicare imaging utilization and expenditures from 2007 to 2011 and to compare these trends with regional variation in other health service categories. METHODS: Data were based on CMS's Chronic Condition Data Warehouse and organized on the basis of 306 US health referral regions (HRRs). Imaging costs per beneficiary, standardized for regional differences in reimbursement rates, and imaging utilization per beneficiary were recorded per HRR from 2007 through 2011. Costs and utilization were also recorded for other service categories in 2011. Regional variation was assessed via relative risk (RR; the ratio between the highest and lowest HRRs) and coefficient of variation (CV; the standard deviation divided by the mean among all HRRs). Correlations between imaging and other service categories were assessed using Pearson's correlation coefficient. RESULTS: There was minimal change in regional variation in imaging costs or utilization between 2007 and 2011. Regional variation in imaging costs (RR, 5.70-5.88; CV, 33.0%-33.3%) was considerably greater than variation in imaging utilization (RR, 2.11%-2.25%; CV, 14.2%-14.6%). Imaging costs and utilization showed moderate to strong correlations with those of other service categories (r = 0.572-0.869). In 2011, regional variation in imaging utilization (RR, 2.25; CV, 14.2%) was considerably lower than variation in utilization of other service categories (RR, 2.80-10.78; CV, 20.9%-33.3%). CONCLUSIONS: Regional variation in imaging utilization is considerably lower than both variation in imaging costs and variation in utilization of other major service categories. It is unclear whether variation in imaging utilization provides an optimal individual target for major policy decisions.

Effect of hospital-SNF referral linkages on rehospitalization.

OBJECTIVE: To determine whether the rate of rehospitalization is lower among patients discharged to skilled nursing facilities (SNFs) with which a hospital has a strong linkage. DATA SOURCES/COLLECTION: We used national Medicare enrollment, claims, and the Minimum Data Set to examine 2.8 million newly discharged patients to 15,063 SNFs from 2,477 general hospitals between 2004 and 2006. STUDY DESIGN: We examined the relationship between the proportion of discharges from a hospital and alternative SNFs on the rehospitalization of patients treated by that hospital-SNF pair using an instrumental variable approach. We used distances to alternative SNFs from residence of the patients of the originating hospital as the instrument. PRINCIPAL FINDINGS: Our estimates suggest that if the proportion of a hospital's discharges to an SNF was to increase by 10 percentage points, the likelihood of patients treated by that hospital-SNF pair to be rehospitalized within 30 days would decline by 1.2 percentage points, largely driven by fewer rehospitalizations within a week of hospital discharge. CONCLUSIONS: Stronger hospital-SNF linkages, independent of hospital ownership, were found to reduce rehospitalization rates. As hospitals are held accountable for patients' outcomes postdischarge under the Affordable Care Act, hospitals may steer their patients preferentially to fewer SNFs.

The increasing role of nonradiologists in performing ultrasound-guided invasive procedures.

PURPOSE: Recent proliferation of mobile diagnostic ultrasound (US) units and improved resolution have allowed for widespread use of US by more providers, both for diagnosis and US-guided procedures (USGP). This study aims to document recent trends in utilization for USGP in the Medicare population. METHODS: Source data were obtained from the CMS Physician Supplier Procedure Summary Master Files from 2004 to 2010. Allowed billing claims submitted for USGP were extracted and volume was analyzed by provider type and setting. Compound annual growth rates were calculated. RESULTS: The total utilization rate for all USGP was 2,425 per 100,000 in 2004 and 4,870 in 2010, an increase of 100.8% (+2,445 per 100,000) with a compound annual growth rate of 12.3%. The year 2010 represents the first year that nonradiologists as a group performed more USGP than radiologists, at 922,672 versus 794,497 examinations, respectively. Nonradiologists accounted for 72.2% (599,751 of 830,925) of the USGP volume growth from 2004 to 2010. Most 2010 claims were submitted by radiologists (n = 794,497; 46.3%) and surgeons (n = 332,294; 19.4%). The largest overall volume increases from 2004 to 2010 were observed among radiologists, surgeons, anesthesiologists, rheumatologists, midlevel providers, primary care physicians, nonrheumatologist internal medicine subspecialists, and the aggregate of all other provider types. CONCLUSION: The year 2010 represents the first year that nonradiologists performed more USGP than radiologists. From 2004 to 2010, radiologists and surgeons experienced only modest growth in USGP volume, whereas several other provider types experienced more rapid growth. It is likely that many procedures that were previously performed without US guidance are now being performed with US guidance.