How Much Perioperative Pain and Dysfunction Underlie the HOOS JR and KOOS JR?

BACKGROUND: The Hip Disability and Osteoarthritis Outcome Score Joint Replacement (HOOS JR) and Knee Injury and Osteoarthritis Outcome Score Joint Replacement (KOOS JR) scores represent pain and dysfunction as a single number ranging from 0 (extreme pain and dysfunction) to 100 (no pain or functional limitations). However, scores between 0 and 100 lack a simple interpretation because they reflect varying combinations of pain levels and dysfunction. Given that most adverse events and improvement occur within the first 90 days after surgery, a deeper understanding of the level of pain and dysfunction may reveal missed opportunities for patient care. QUESTIONS/PURPOSES: (1) What does a given preoperative or postoperative HOOS JR and KOOS JR score indicate about pain and ability to perform daily activities? (2) How much of a change in score (that is, delta) is needed to indicate significant improvement in pain control and daily functioning? METHODS: The Michigan Arthroplasty Registry Collaborative Quality Initiative contains more than 95% of THAs and TKAs performed in Michigan. Between January 2017 and March 2019, 84,175 people in the registry underwent primary THA or TKA and were potentially eligible for this retrospective, comparative study of the first 90 postoperative days. Eighty-four percent (70,608 of 84,175) were excluded because their surgeons did not attain a target survey collection proportion of 70% and another 6% (5042) were missing covariate information or surveys, leaving 10% (8525) for analysis. The mean age and percentage of women were 65 ± 11 years and 55% (2060 of 3716), respectively, for patients undergoing THA and 67 ± 9 years and 61% (2936 of 4809), respectively, for those undergoing TKA. There were no clinically meaningful differences between patients who were analyzed and those who were excluded except for lower representation of non-White patients in the analyzed group. For interpretation, patient responses to Question 7 (pain) and Question 6 (function) from the Patient-Reported Outcomes Measurement Information System global items (PROMIS-10) were dichotomized into "much pain" (rating of pain 4 to 10 of 10) versus "less pain" (rating of ≤ 3) and "good function" (able to perform most activities) versus "poor function" (not able to perform most activities) and combined into four pain-function categories. We examined the mean preoperative and postoperative HOOS JR and KOOS JR scores for each pain-function category, adjusted for patient characteristics. We calculated the size of the delta associated with an increase to a more favorable category postoperatively (versus staying in the same or worse category) via multivariable logistic regression that controlled for patient characteristics. RESULTS: Patients in the least favorable "much pain, poor function" category preoperatively had adjusted mean scores of 40 (95% confidence interval 39 to 41) for both the HOOS JR and KOOS JR. Those with mixed levels of pain and function had mean scores between 46 and 55. Those in the most favorable "less pain, good function" category had means of 60 (95% CI 58 to 62) and 59 (95% CI 58 to 61) for the HOOS JR and KOOS JR, respectively. The adjusted delta to achieve a pain level of ≤ 3 or the ability to perform most activities was 30 (95% CI 26 to 36) on the HOOS JR and 27 (95% CI 22 to 29) on the KOOS JR scales. CONCLUSION: These adjusted means of the HOOS JR and KOOS JR provide context for understanding the levels of pain and dysfunction for individuals as well for patients reported in other studies. Potential quality improvement efforts could include tracking the proportion of patients with THA or TKA who achieved a sufficient delta to attain pain levels of ≤ 3 or the ability to perform most activities. Future studies are needed to understand pain and function represented by the HOOS JR and KOOS JR at 1 to 2 years, how these may differ by patient subgroups, and whether scores can be improved through quality improvement efforts. LEVEL OF EVIDENCE: Level III, therapeutic study.

Non-Inferiority of Aspirin for Venous Thromboembolism Prophylaxis After Hip Arthroplasty in a Statewide Registry.

BACKGROUND: Uncertainty remains surrounding the use of aspirin as a sole chemoprophylactic agent to reduce the risk of venous thromboembolism (deep vein thrombosis or pulmonary embolism) and bleeding after primary total hip arthroplasty. METHODS: We performed a non-inferiority analysis of a retrospective cohort of patients undergoing total hip arthroplasty from April 1, 2013 to December 31, 2018. Cases were retrieved from the Michigan Arthroplasty Registry Collaborative Quality Initiative database and performed by 355 surgeons at 61 hospitals throughout Michigan. Surgical setting ranged from small community hospitals to large academic and non-academic centers. The primary outcomes were post-operative venous thromboembolism event or death and bleeding event. RESULTS: Of the 59,747 patients included, 32,878 (55.03%) were female, and the mean age was 64.5. A total of 462 (0.77%) composite venous thromboembolism events occurred. There were 221 (0.71%) and 129 (0.80%) venous thromboembolism events in patients receiving aspirin only and anticoagulants only, respectively. Aspirin was non-inferior to anticoagulants for composite venous thromboembolism events (odds ratio 0.99, 95% confidence interval 0.79-1.26, P < .001). Bleeding events occurred in 767 (1.28%) patients, with 304 (0.97%) and 281 (1.74%) bleeding events in patients receiving aspirin only and anticoagulants only, respectively. Aspirin was non-inferior to anticoagulants for bleeding events (odds ratio 0.62, 95% confidence interval 0.52-0.74, P < .001). CONCLUSION: Aspirin is not inferior to other anticoagulants as pharmacologic venous thromboembolism prophylaxis with regards to post-operative risk of venous thromboembolism or bleeding. Sole use of aspirin for venous thromboembolism prophylaxis after total hip arthroplasty should be considered in the appropriate patient.

Validation of a prospective mortality prediction score for hip fracture patients.

PURPOSE: Although mortality prediction tools are the subject of significant interest as components of comprehensive hip fracture protocols, few have been applied or validated to prospectively inform ongoing patient management. Five regional hospitals are currently generating real-time mortality risk scores for all adults at the time of admission using available laboratory and comorbidity data (Cowen et al. J Hosp Med 9(11):720-726, 2014). Although results for aggregated conditions have been published, the primary aim of this study is to determine how well prospectively calculated scores predict mortality for hip fracture patients specifically. METHODS: Using a five-hospital database, 1376 patients who were prospectively scored on admission were identified from January 2013 to April 2017, cross-referencing ICD9/10 diagnosis and procedure codes for AO/OTA 31A1 through 31B3 fractures. Prospective mortality scores have been previously divided into 5 risk categories to facilitate ease of clinical use. Vital status was determined from hospital data, Social Security and Michigan Death Indices. RESULTS: Prospective scores demonstrated good mortality prediction, with AUCs of 0.80, 0.73, 0.74 and 0.74 for in hospital, 30-, 60- and 90-day mortality, respectively. Patients in the top 2 mortality risk categories represented 30% (410/1376) of the cohort and accounted for 78% (25/32) of the inpatient and 59% (57/97) of the 30 day deaths. CONCLUSIONS: Implementation of this real-time mortality risk tool is feasible and valid for the prediction of short- to medium-term mortality risk for hip fracture patients, and potentially offers valuable information to guide ongoing patient management decisions such as admitting service or level of care.

Common Risk Stratification of Hospital and Ambulatory Patients.

The care of patients with multiple chronic conditions and those near the end-of-life is often compromised by miscommunications among the healthcare teams. These might be improved by using common risk strata for both hospital and ambulatory settings. We developed, validated, and implemented an all-payer ambulatory risk stratification based on the patients' predicted probability of dying within 30 days, for a large multispecialty practice. Strata had comparable 30-day mortality rates to hospital strata already in use. The high-risk ambulatory strata contained less than 20% of the ambulatory population yet captured 85% of those with 3 or more comorbidities, more than 80% of those who would die 30 or 180 days from the date of scoring, and two-thirds of those with a nonsurgical hospitalization within the next 30 days. We provide examples how the practice and partner hospital have begun to use this common framework for their clinical care model.

Data-driven optimization methodology for admission control in critical care units.

The decision of whether to admit a patient to a critical care unit is a crucial operational problem that has significant influence on both hospital performance and patient outcomes. Hospitals currently lack a methodology to selectively admit patients to these units in a way that patient health risk metrics can be incorporated while considering the congestion that will occur. The hospital is modeled as a complex loss queueing network with a stochastic model of how long risk-stratified patients spend time in particular units and how they transition between units. A Mixed Integer Programming model approximates an optimal admission control policy for the network of units. While enforcing low levels of patient blocking, we optimize a monotonic dual-threshold admission policy. A hospital network including Intermediate Care Units (IMCs) and Intensive Care Units (ICUs) was considered for validation. The optimized model indicated a reduction in the risk levels required for admission, and weekly average admissions to ICUs and IMCs increased by 37% and 12%, respectively, with minimal blocking. Our methodology captures utilization and accessibility in a network model of care pathways while supporting the personalized allocation of scarce care resources to the neediest patients. The interesting benefits of admission thresholds that vary by day of week are studied.

Association of Aspirin With Prevention of Venous Thromboembolism in Patients After Total Knee Arthroplasty Compared With Other Anticoagulants: A Noninferiority Analysis.

Importance: There has been significant debate in the surgical and medical communities regarding the appropriateness of using aspirin alone for venous thromboembolism (VTE) prophylaxis following total knee arthroplasty (TKA). Objective: To determine the acceptability of aspirin alone vs anticoagulant prophylaxis for reducing the risk of postoperative VTE in patients undergoing TKA. Design, Setting, and Participants: Noninferiority study of a retrospective cohort of TKA cases submitted to the Michigan Arthroplasty Registry Collaborative Quality Initiative at 29 member hospitals, ranging from small community hospitals to large academic and nonacademic medical centers in Michigan. The study included 41 537 patients who underwent primary TKA between April 1, 2013, and October 31, 2015. Clinical events were monitored for 90 days after surgery. Data were analyzed between September and October 2016. Exposures: The method of pharmacologic prophylaxis: neither aspirin nor anticoagulants for 668 patients (1.6%), aspirin only for 12 831 patients (30.9%), anticoagulant only (eg, low-molecular-weight heparin, warfarin, and Xa inhibitors) for 22 620 patients (54.5%), and both aspirin/anticoagulant for 5418 patients (13.0%). Most patients were also using intermittent pneumatic compression stockings. Main Outcome and Measures: The primary composite outcome was the first occurrence of VTE or death. The noninferiority margin was specified as 0.3. The secondary outcome was bleeding events. Results: Of the 41 537 patients, 14 966 were men (36%), and the mean age was 65.8 years. A VTE event occurred in 573 of 41 537 patients (1.38%); 32 of 668 (4.79%) who received no pharmacologic prophylaxis, 149 of 12 831 (1.16%) treated with aspirin alone, 321 of 22 620 (1.42%) with anticoagulation alone, and 71 of 5418 (1.31%) prescribed both aspirin and anticoagulation. Aspirin only was noninferior for the composite VTE outcome compared with those receiving other chemoprophylaxis (adjusted odds ratio, 0.85; 95% CI, 0.68-1.07, P for inferiority = .007). Bleeding occurred in 457 of 41 537 patients (1.10%), 10 of 668 (1.50%) without prophylaxis, 116 of 12 831 (0.90%) in the aspirin group, 258 of 22 620 (1.14%) with anticoagulation, and 73 of 5418 (1.35%) of those receiving both. Aspirin alone was also noninferior for bleeding complications (adjusted odds ratio, 0.80; 95% CI, 0.63-1.00, P for inferiority <.001). Conclusions and Relevance: In this study of patients undergoing TKA, aspirin was not inferior to other anticoagulants in the postoperative rate of VTE or death. Aspirin alone may provide similar protection from postoperative VTE compared with other anticoagulation treatments.

The Michigan Arthroplasty Registry Collaborative Quality Initiative Experience: Improving the Quality of Care in Michigan.

The Michigan Arthroplasty Registry Collaborative Quality Initiative (MARCQI) is a regional quality improvement effort that is focused on hip and knee arthroplasty. From its inception in 2012, MARCQI has grown to include data from 66 hospitals and surgery centers, and contains over 209,000 fully abstracted cases in its database. Using high-quality risk-standardized outcomes data, MARCQI drives quality improvement through a collaborative and nonpunitive structure. Quality improvement initiatives have included transfusion reduction, infection prevention, venous thromboembolism reduction, and reduction of discharge to nursing homes. In addition, MARCQI focuses on postmarket surveillance of implants by computing revision-risk estimates based on the cases that were registered prior to the end of 2016. This paper describes the impact of MARCQI on the quality of hip and knee arthroplasty care in the state of Michigan since its inception in 2012, and it briefly summarizes the recently released 5-year report.

The Michigan Experience with Safety and Effectiveness of Tranexamic Acid Use in Hip and Knee Arthroplasty.

BACKGROUND: The efficacy of tranexamic acid (TXA) in reducing blood loss and transfusion requirements in total hip and knee arthroplasty has been well established in small controlled clinical trials and meta-analyses. The purpose of the current study was to determine the risks and benefits of TXA use in routine orthopaedic surgical practice on the basis of data from a large, statewide arthroplasty registry. METHODS: From April 18, 2013, to September 30, 2014, there were 23,236 primary total knee arthroplasty cases and 11,489 primary total hip arthroplasty cases completed and registered in the Michigan Arthroplasty Registry Collaborative Quality Initiative (MARCQI). We evaluated the association between TXA use and hemoglobin drop, transfusion, length of stay (LOS), venous thromboembolism (VTE), readmission, and cardiovascular events by fitting mixed-effects generalized linear and mixed-effects Cox models. We used inverse probability of treatment weighting to enhance causal inference. RESULTS: For total hip arthroplasty, TXA use was associated with a smaller drop in hemoglobin (mean difference = -0.65 g/dL; 95% confidence interval [CI] = -0.60 to -0.71 g/dL), decreased odds of blood transfusion (odds ratio [OR] = 0.72; 95% CI = 0.60 to 0.86), and decreased readmissions (OR = 0.77; 95% CI = 0.64 to 0.93) compared with no TXA use. There was no effect on VTE (hazard ratio [HR] = 0.91; 95% CI = 0.62 to 1.33), LOS (incident rate ratio [IRR] = 1.00; 95% CI = 0.97 to 1.03), or cardiovascular events (OR = 0.85; 95% CI = 0.47 to 1.52). For total knee arthroplasty, TXA was associated with a smaller drop in hemoglobin (mean difference = -0.68 g/dL; 95% CI = -0.64 to -0.71 g/dL) and one-fourth the odds of blood transfusion (OR = 0.26; 95% CI = 0.21 to 0.31). There was an association with decreased risk of VTE within 90 days after surgery (HR = 0.56; 95% CI = 0.42 to 0.73), slightly decreased LOS (IRR = 0.93; 95% CI = 0.92 to 0.95), and no association with readmissions (OR = 0.90; 95% CI = 0.79 to 1.04) or cardiovascular events (OR = 1.12; 95% CI = 0.74 to 1.71). CONCLUSIONS: In routine orthopaedic surgery practice, TXA use was associated with decreased blood loss and transfusion risk for both total knee and total hip arthroplasty, without evidence of increased risk of complications. TXA use was also associated with reduced risk of readmission among total hip arthroplasty patients and reduced risk of VTE among total knee arthroplasty patients, and did not have an adverse effect on cardiovascular complications in either group. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

The risk-outcome-experience triad: Mortality risk and the hospital consumer assessment of healthcare providers and systems survey.

BACKGROUND: Studies have shown an association between the Hospital Consumer Assessment of Healthcare Providers and Systems Survey (HCAHPS) scores and clinical quality. The mortality risk on admission predicts adverse events. It is not known if this risk also portends a suboptimal patient experience. OBJECTIVE: To determine if the admission mortality risk identifies an experience of care risk. DESIGN: A retrospectively assembled cohort in which individual HCAHPS survey responses were linked to the admission risk of dying. SETTING: Five community hospitals of various sizes in Michigan. PATIENTS: There were 17,509 HCAHPS medical and surgical respondents; 2513 (14.4%) were at high risk of dying. MEASUREMENTS: Odds ratio (OR) (high-risk patients to low-risk patients) for providing a top box score for HCAHPS dimensions, controlling for hospital and the standard HCAHPS patient mix adjustment factors. RESULTS: High-risk respondents were less likely to provide the most favorable response (unadjusted) for all HCAHPS domains, although the difference was not significant (P = 0.09) for discharge information. Multivariable analyses indicated that high-risk patients were less likely to report a top box experience for doctor communication (OR: 0.85; 95% confidence interval [CI]: 0.77-0.94) and responsiveness of hospital staff (OR: 0.77; 95% CI: 0.69-0.85), but were more likely to have received adequate discharge information (OR: 1.30, 95% CI: 1.14-1.48). CONCLUSIONS: Patients at high risk of dying who completed surveys were less likely to report favorable physician communication and staff responsiveness. Further understanding of these relationships may help design a care model to improve both outcomes and experience. Journal of Hospital Medicine 2016;11:628-635. © 2016 Society of Hospital Medicine.

Implementation of a mortality prediction rule for real-time decision making: feasibility and validity.

BACKGROUND: A previously published, retrospectively derived prediction rule for death within 30 days of hospital admission has the potential to launch parallel interdisciplinary team activities. Whether or not patient care improves will depend on the validity of prospectively generated predictions, and the feasibility of generating them on demand for a critical proportion of inpatients. OBJECTIVE: To determine the feasibility of generating mortality predictions on admission and to validate their accuracy using the scoring weights of the retrospective rule. DESIGN: Prospective, sequential cohort. SETTING: Large, tertiary care, community hospital in the Midwestern United States PATIENTS: Adult patients admitted from the emergency department or scheduled for elective surgery RESULTS: Mortality predictions were generated on demand at the beginning of the hospitalization for 9312 (92.9%) out of a possible 10,027 cases. The area under the receiver operating curve for 30-day mortality was 0.850 (95% confidence interval: 0.833-0.866), indicating very good to excellent discrimination. The prospectively generated 30-day mortality risk had a strong association with the receipt of palliative care by hospital discharge, in-hospital mortality, and 180-day mortality, a fair association with the risk for 30-day readmissions and unplanned transfers to intensive care, and weak associations with receipt of intensive unit care ever within the hospitalization or the development of a new diagnosis that was not present on admission (ie, complication). CONCLUSIONS: Important prognostic information is feasible to obtain in a real-time, single-assessment process for a sizeable proportion of hospitalized patients.

Randomized controlled effectiveness trial of reciprocal peer support in heart failure.

BACKGROUND: Although disease management programs for patients hospitalized with heart failure (HF) are effective, they are, however, often resource intensive, limiting their uptake. Peer support programs have led to improved outcomes among patients with other chronic conditions and may result in similar improvements for patients with HF. METHODS AND RESULTS: In this randomized controlled trial, reciprocal peer support (RPS) arm patients participated in a HF nurse practitioner-led goal setting group session, received brief training in peer communication skills, and were paired with another participant in their cohort with whom they were encouraged to talk weekly using a telephone platform. Participants were also encouraged to attend 3 nurse practitioner-facilitated peer support group sessions. Patients in the nurse care management arm attended a nurse practitioner-led session to address their HF care questions and receive HF educational materials and information on how to access care management services. The median age of the patients was 69 years; 51% were female and 26% were racial/ethnic minorities. Only 55% of RPS patients participated in peer calls or group sessions. In intention-to-treat analyses, the RPS and nurse care management groups did not differ in time-to-first all-cause rehospitalization or death or in mean numbers of rehospitalizations or deaths. There were no differences in improvements in 6-month measures of HF-specific quality of life or social support. Conclusions- Among patients recently hospitalized for HF, more than half of RPS participants had no or minimal engagement with the RPS program, and the program did not improve outcomes compared with usual HF nurse care management. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. UNIQUE IDENTIFIER: NCT00508508.

Mortality predictions on admission as a context for organizing care activities.

BACKGROUND: Favorable health outcomes are more likely to occur when the clinical team recognizes patients at risk and intervenes in consort. Prediction rules can identify high-risk subsets, but the availability of multiple rules for various conditions present implementation and assimilation challenges. METHODS: A prediction rule for 30-day mortality at the beginning of the hospitalization was derived in a retrospective cohort of adult inpatients from a community hospital in the Midwestern United States from 2008 to 2009, using clinical laboratory values, past medical history, and diagnoses present on admission. It was validated using 2010 data from the same and from a different hospital. The calculated mortality risk was then used to predict unplanned transfers to intensive care units, resuscitation attempts for cardiopulmonary arrests, a condition not present on admission (complications), intensive care unit utilization, palliative care status, in-hospital death, rehospitalizations within 30 days, and 180-day mortality. RESULTS: The predictions of 30-day mortality for the derivation and validation datasets had areas under the receiver operating characteristic curve of 0.88. The 30-day mortality risk was in turn a strong predictor for in-hospital death, palliative care status, 180-day mortality; a modest predictor for unplanned transfers and cardiopulmonary arrests; and a weaker predictor for the other events of interest. CONCLUSIONS: The probability of 30-day mortality provides health systems with an array of prognostic information that may provide a common reference point for organizing the clinical activities of the many health professionals involved in the care of the patient.

Duration of evidence-based medical therapy and the hazard for atherothrombotic events following percutaneous coronary intervention.

BACKGROUND: Patients who undergo coronary artery stent procedures are at risk for late atherothrombotic events, including stent thrombosis. The relationship between the duration during which evidence-based medical therapies are utilized after coronary artery stenting and the risk of late atherothrombotic events is not well characterized. METHODS: In a retrospective cohort study linking a hospital-based percutaneous coronary intervention registry with a health maintenance organization claims dataset, we related the duration of medical therapy utilization during follow up to the hazard for death, myocardial infarction, unstable angina, transient ischemic attack or stroke following a coronary artery stent procedure. Multivariable Cox models were employed in which medical treatments were entered as time-varying covariates; data were stratified by stent type and time period. RESULTS: The median [interquartile range, IQR] duration of follow up was 832 [460, 1420] days. During this time, 86 ischemic events occurred in 84 of 386 patients at a median [IQR] of 260 [110, 658] days. The incidence of atherothrombotic events following coronary artery stenting was highest during the first post-procedure year and declined substantially thereafter. Multivariable predictors of incident ischemic events included multivessel coronary artery disease (HR 2.01 [95% CI 1.30-3.11], p=0.0018) and longer duration angiotensin converting enzyme (ACE) inhibitor/angiotensin receptor blocker (ARB), beta blocker or statin therapy (HR 0.52 [95% CI 0.28-0.99], p=0.045). CONCLUSIONS: The use of longer-term ACE inhibitor/ARB, beta blocker or statin therapy was associated with a significantly lower risk; these risk reductions were of greater magnitude than those associated with clopidogrel.

The inability of B-type natriuretic protein to predict short-term risk of death or myocardial infarction in non-heart-failure patients with marginally increased troponin levels.

STUDY OBJECTIVE: We want to know whether a low B-type natriuretic peptide (BNP) level, obtained shortly after presentation and independent of information provided by other clinical findings and laboratory tests, would affect management decisions for emergency department (ED) patients with nondiagnostic troponin levels. Previous studies have generally been retrospective or inclusive of patients with heart failure. METHODS: We prospectively studied patients evaluated for possible acute coronary syndromes who had nondiagnostic levels of serum troponin, nondiagnostic ECGs, and no clinical heart failure within 4 hours of presentation. BNP levels were obtained but results not provided to clinical staff. The primary outcome was the composite of acute myocardial infarction or death within 30 days. The secondary outcome was the composite of the primary outcome, percutaneous coronary intervention, or coronary artery bypass grafting. RESULTS: Almost half of the patients screened for but excluded from the study had known heart failure or a history of heart failure. The resulting cohort was composed of 348 patients, with a median age of 64 years and 51% women. The primary outcome occurred in 16.1% of patients; the secondary outcome, in 27.6%. At a standard cutoff of BNP greater than or equal to 80 pg/mL, the negative predictive value for the primary outcome was 80% (95% confidence interval 73% to 86%). The negative predictive value for the secondary outcome was 69% (95% confidence interval 61% to 75%). Multivariable analyses supported these findings. CONCLUSION: A single, low BNP level obtained shortly after presentation to the ED could not identify patients at low risk for 30-day acute myocardial infarction or death.

A flexible two-part random effects model for correlated medical costs.

In this paper, we propose a flexible "two-part" random effects model (Olsen and Schafer, 2001; Tooze et al., 2002) for correlated medical cost data. Typically, medical cost data are right-skewed, involve a substantial proportion of zero values, and may exhibit heteroscedasticity. In many cases, such data are also obtained in hierarchical form, e.g., on patients served by the same physician. The proposed model specification therefore consists of two generalized linear mixed models (GLMM), linked together by correlated random effects. Respectively, and conditionally on the random effects and covariates, we model the odds of cost being positive (Part I) using a GLMM with a logistic link and the mean cost (Part II) given that costs were actually incurred using a generalized gamma regression model with random effects and a scale parameter that is allowed to depend on covariates (cf., Manning et al., 2005). The class of generalized gamma distributions is very flexible and includes the lognormal, gamma, inverse gamma and Weibull distributions as special cases. We demonstrate how to carry out estimation using the Gaussian quadrature techniques conveniently implemented in SAS Proc NLMIXED. The proposed model is used to analyze pharmacy cost data on 56,245 adult patients clustered within 239 physicians in a mid-western U.S. managed care organization.

An electronic strategy to identify hospitalized heart failure patients.

BACKGROUND: A common challenge in improving performance measures regarding heart failure (HF) is identifying patients early in the course of their hospitalization so that multidisciplinary education and clinical interventions can be implemented. We describe the accuracy of using an electronic pharmacy-based strategy to identify hospitalized patients likely to have a principal diagnosis of HF at discharge. METHODS: We evaluated 2 strategies. The first used the receipt of an intravenous loop diuretic as a single predictor; the second incorporated additional lab, pharmacy, and demographic information in a multivariable general estimating equation. RESULTS: Receipt of an intravenous diuretic predicted a discharge diagnosis of heart failure with a sensitivity of 0.89 and a specificity of 0.87. Adding age, B-type natriuretic peptide level, previous hospitalizations, attending physician specialty, and receipt of spironolactone into the predictor improved the sensitivity to 0.91 and the specificity to 0.89. CONCLUSIONS: The receipt of intravenous loop diuretics is a reasonable and easily implemented screening test to identify patients likely to have a principal diagnosis of heart failure at discharge. The accuracy is improved by incorporating other electronically available variables.

Predictors and outcomes of emergency department visits within 30 days following percutaneous coronary intervention.

Our objective was to determine the frequency and predictive factors for cardiac-related emergency department (ED) encounters within 30 days after percutaneous coronary intervention (PCI). The data source was an electronic database of 2,731 patients who had PCI from 2002 to 2004. Almost all underwent stent placement. Risk factors for returning to the ED were identified from clinical, anatomic, and demographic candidate variables using multivariate logistic regression. Approximately 9% of the cohort (255 of 2,731 patients) returned to the ED for cardiac reasons within 30 days, peaking around 3 days. ED visits were more likely in those whose index PCI was emergent or urgent (odds ratio [OR] 2.0, 95% confidence interval [CI] 1.3 to 3.0), in women (OR 1.9, 95% CI 1.5 to 2.5), and in those who had previous encounters with the ED or hospital (OR 1.7, 95% CI 1.5 to 2.0). Patients receiving stents were somewhat less likely to return (OR 0.7, 95% CI 0.5 to 1.0). In conclusion, the clinical courses of the 255 returning patients were generally benign, but 12% had a subsequent myocardial infarction or repeat PCI within 30 days of the ED encounter.

Predicting life expectancy in men with clinically localized prostate cancer.

PURPOSE: The choice of appropriate management for localized prostate cancer depends in part on the estimated life expectancy of a man. Little is known about the accuracy of existing rules for deriving these estimates. We developed a new prediction rule and examined the accuracy of 2 others in our data set. MATERIALS AND METHODS: A retrospective cohort was assembled, consisting of 506 men who were diagnosed or received initial treatment at a community based, tertiary care health center between 1987 and 1989 for clinically localized prostate cancer (stages A, B, I, II or T1-2N0M0) and had at least 13 years of followup. Most patients did not have prostate specific antigen levels available. Proportional hazards regression was used to create a nomogram for deriving survival estimates. Discrimination of the new and external prediction rules was assessed by the c-statistic. Calibration curves compared predicted to actual survival at 10 years. RESULTS: Estimates for survival at 5, 10 and 15 years, and for median life expectancy were determined. Discrimination was modest with a c-statistic of 0.73. The rules of Albertsen and Tewari et al had comparable discrimination in our data with a c-statistic of 0.71 and 0.70, respectively. Predicted life expectancy according to our rule and that of Tewari approximated actual survival experience. Predictions according to the Albertsen study underestimated actual survival in our group but in consistent fashion. CONCLUSIONS: Overall life expectancy can be predicted with a moderate degree of accuracy, sufficient for informing patient-clinician discussions but inadequate as the only determinant of the optimal management approach.

A comparison of two hospitalist models with traditional care in a community teaching hospital.

PURPOSE: Many studies have documented significant length of stay reduction and cost savings when hospitalist care is compared with traditional care. However, less is known about the concurrent performance of more than one hospitalist model in a single site. SUBJECTS AND METHODS: This retrospective cohort study of 10595 patients was conducted between July 2001 and June 2002 in a tertiary care community-based teaching hospital. Risk-adjusted length of stay, variable costs, 30-day readmission rates, and in-hospital and 30-day mortality were measured for patients treated by Community Physicians, Private Hospitalists and Academic Hospitalists. RESULTS: There was a 20% reduction in length of stay on the Academic Hospitalist service (p <.0001) and 8% on the Private Hospitalist service (P = .049) compared with Community Physicians. Similarly, total costs were 10% less on the Academic (P <.0001) and 6% less on the Private Hospitalist (P = .02) services compared with Community Physicians. The length of stay of Academic Hospitalists was 13% shorter than that of Private Hospitalists (P = .002); differences in costs between hospitalist groups were not statistically significant. Differences in in-hospital and 30-day mortality and 30-day readmission rates among the 3 physician groups were also not statistically significant. CONCLUSIONS: The impact on patient outcomes and resource utilization may vary with the hospitalist model used. Future studies should examine the specific organizational characteristics of hospitalists that contribute to improved patient care and resource utilization.

Preference assessment method affects decision-analytic recommendations: a prostate cancer treatment example.

PURPOSE: To evaluate the effect of preference assessment method on treatment recommended by an individualized decision-analytic model for early prostate cancer. METHODS: Health state preferences were elicited by time tradeoff, rating scale, and a power transformation of the rating scale from 63 men ages 55 to 75. The authors used these values in a Markov model to determine whether radical prostatectomy or watchful waiting yielded the greater quality-adjusted life expectancy. RESULTS: Time tradeoff and transformed rating scale recommendations differed widely. Time tradeoff and transformed rating scale utilities differed in their treatment recommendation for 21% to 52% of men, and the mean difference in quality-adjusted life years varied from less than 0.5 to greater than 1.0. CONCLUSIONS: Treatment recommendations from the prostate cancer decision model were sensitive to the method of preference assessment. If decision analysis is used to counsel individual patients, careful consideration must be given to the method of preference elicitation.