George J. Stukenborg

Comparison of the performance of two comorbidity measures, with and without information from prior hospitalizations.

Objectives.This study compares the performance of two comorbidity risk adjustment methods (the Deyo et al adaptation of the Charlson index and the Elixhauser et al method) in five groups of California hospital patients with common reasons for hospitalization, and assesses the contribution to model performance made by information drawn from prior hospital admissions. Methods.California hospital discharge abstract data for the calendar years 1994 through 1997 were used to create a longitudinal data set for patients in the five disease groups. Eleven logistic regression models were estimated to predict the risk of in-hospital death for patients in each group, with both comorbidity risk adjustment methods applied to patient information available from only the index hospitalization, and to information available from both the index and prior hospitalizations. Results.For every comparison made, the level of statistical performance (area under the receiver operating characteristics curve) demonstrated by models using the Elixhauser et al method was superior to that of models using the Deyo et al adaptation method. Although most patients have information available from prior hospital admissions, this additional information yields only small improvements in the performance of models using either comorbidity risk adjustment method. Conclusions.Better discrimination is achieved with the Elixhauser et al method using only information from the index hospitalization than is achieved with the Deyo et al adaptation using information from all identified hospital admissions. Both comorbidity risk adjustment methods achieve their best performance when information from the index hospitalization and prior admissions is separated into independent indicators of comorbid illness.

Cancer incidence after localized therapy for prostate cancer

Second cancers may occur in patients who have undergone radiation therapy. The risk for these adverse events after therapy is uncertain. In this study, the authors examined the size and significance of the observed association between occurrences of secondary cancers 5 years after radiotherapy in a large population of men with incident prostate cancer.

Bundle-Branch Block Morphology and Other Predictors of Outcome After Cardiac Resynchronization Therapy in Medicare Patients

Background— Clinical trials of cardiac resynchronization therapy (CRT) have enrolled a select group of patients, with few patients in subgroups such as right bundle-branch block (RBBB). Analysis of population-based outcomes provides a method to identify real-world predictors of CRT outcomes. Methods and Results— Medicare Implantable Cardioverter-Defibrillator Registry (2005 to 2006) data were merged with patient outcomes data. Cox proportional-hazards models assessed death and death/heart failure hospitalization outcomes in patients with CRT and an implantable cardioverter-defibrillator (CRT-D). The 14 946 registry patients with CRT-D (median follow-up, 40 months) had 1-year, 3-year, and overall mortality rates of 12%, 32%, and 37%, respectively. New York Heart Association class IV heart failure status (1-year hazard ratio [HR], 2.23; 3-year HR, 1.98; P<0.001) and age ≥80 years (1-year HR, 1.74; 3-year HR, 1.75; P<0.001) were associated with increased mortality both early and late after CRT-D. RBBB (1-year HR, 1.44; 3-year HR, 1.37; P<0.001) and ischemic cardiomyopathy (1-year HR, 1.39; 3-year HR, 1.44; P<0.001) were the next strongest adjusted predictors of both early and late mortality. RBBB and ischemic cardiomyopathy together had twice the adjusted hazard for death (HR, 1.99; P<0.001) as left BBB and nonischemic cardiomyopathy. QRS duration of at least 150 ms predicted more favorable outcomes in left BBB but had no impact in RBBB. A secondary analysis showed lower hazards for CRT-D compared with standard implantable cardioverter-defibrillators in left BBB compared with RBBB. Conclusions— In Medicare patients, RBBB, ischemic cardiomyopathy, New York Heart Association class IV status, and advanced age were powerful adjusted predictors of poor outcome after CRT-D. Real-world mortality rates 3 to 4 years after CRT-D appear higher than previously recognized.

Mortality reduction by heart rate characteristic monitoring in very low birth weight neonates: A randomized trial

OBJECTIVE To test the hypothesis that heart rate characteristics (HRC) monitoring improves neonatal outcomes. STUDY DESIGN We conducted a two-group, parallel, individually randomized controlled clinical trial of 3003 very low birth weight infants in 9 neonatal intensive care units. In one group, HRC monitoring was displayed; in the other, it was masked. The primary outcome was number of days alive and ventilator-free in the 120 days after randomization. Secondary outcomes were mortality, number of ventilator days, neonatal intensive care unit stay, and antibiotic use. RESULTS The mortality rate was reduced in infants whose HRC monitoring was displayed, from 10.2% to 8.1% (hazard ratio, 0.78; 95% CI, 0.61-0.99; P = .04; number needed to monitor = 48), and there was a trend toward increased days alive and ventilator-free (95.9 of 120 days compared with 93.6 in control subjects, P = .08). The mortality benefit was concentrated in infants with a birth weight <1000 g (hazard ratio, 0.74; 95% CI, 0.57-0.95; P = .02; number needed to monitor = 23). There were no significant differences in the other outcomes. CONCLUSION HRC monitoring can reduce the mortality rate in very low birth weight infants.

Primary payer status affects mortality for major surgical operations.

Objectives:Medicaid and Uninsured populations are a significant focus of current healthcare reform. We hypothesized that outcomes following major surgical operations in the United States is dependent on primary payer status. Methods:From 2003 to 2007, 893,658 major surgical operations were evaluated using the Nationwide Inpatient Sample (NIS) database: lung resection, esophagectomy, colectomy, pancreatectomy, gastrectomy, abdominal aortic aneurysm repair, hip replacement, and coronary artery bypass. Patients were stratified by primary payer status: Medicare (n = 491,829), Medicaid (n = 40,259), Private Insurance (n = 337,535), and Uninsured (n = 24,035). Multivariate regression models were applied to assess outcomes. Results:Unadjusted mortality for Medicare (4.4%; odds ratio [OR], 3.51), Medicaid (3.7%; OR, 2.86), and Uninsured (3.2%; OR, 2.51) patient groups were higher compared to Private Insurance groups (1.3%, P < 0.001). Mortality was lowest for Private Insurance patients independent of operation. After controlling for age, gender, income, geographic region, operation, and 30 comorbid conditions, Medicaid payer status was associated with the longest length of stay and highest total costs (P < 0.001). Medicaid (P < 0.001) and Uninsured (P < 0.001) payer status independently conferred the highest adjusted risks of mortality. Conclusions:Medicaid and Uninsured payer status confers increased risk-adjusted mortality. Medicaid was further associated with the greatest adjusted length of stay and total costs despite risk factors or operation. These differences serve as an important proxy for larger socioeconomic and health system-related issues that could be targeted to improve surgical outcomes for US Patients.

Influence of Weekend Hospital Admission on Short-Term Mortality After Intracerebral Hemorrhage

Background and Purpose— There is expanding literature to show that certain patients admitted during the weekend have worse outcomes than similar patients admitted during the week. Although many clinicians have hypothesized the presence of this “weekend effect” with patients with intracerebral hemorrhage, there is a paucity of studies validating this conjecture. Methods— We performed a retrospective cohort study of patients with intracerebral hemorrhage (International Classification of Diseases, 9th Revision, Clinical Modification=431) extracted from the 2004 Nationwide Inpatient Sample. Multivariable logistic regression analyses and Cox proportional hazards regression were conducted to calculate the odds of death (within 7, 14, and 30 days) and the hazard ratio of death for patients with weekend intracerebral hemorrhage admissions compared with weekday intracerebral hemorrhage admissions. All analyses were adjusted for concurrent differences in length of stay, patient demographics, and comorbid disease. Results— Weekend hospital admissions accounted for 26.8% of the 13 821 patients with a diagnosis of intracerebral hemorrhage in the National Inpatient Sample. Admission during the weekend was a statistically significant independent predictor of death within 7 days (OR, 1.14; 95% CI, 1.05 to 1.25), within 14 days (OR, 1.15; 95% CI, 1.05 to 1.25), and within 30 days (OR, 1.15; 95% CI, 1.05 to 1.25). The adjusted hazard of in-hospital death (hazard ratio, 1.12; CI, 1.05 to 1.20) indicates that the overall risk of in-hospital death with intracerebral hemorrhage is 12% higher with weekend admission. Conclusion— Weekend admission for intracerebral hemorrhage was associated with increased risk-adjusted mortality when compared with admission during the remainder of the week.

Impact of Mechanical Activation, Scar, and Electrical Timing on Cardiac Resynchronization Therapy Response and Clinical Outcomes

OBJECTIVES Using cardiac magnetic resonance (CMR), we sought to evaluate the relative influences of mechanical, electrical, and scar properties at the left ventricular lead position (LVLP) on cardiac resynchronization therapy (CRT) response and clinical events. BACKGROUND CMR cine displacement encoding with stimulated echoes (DENSE) provides high-quality strain for overall dyssynchrony (circumferential uniformity ratio estimate [CURE] 0 to 1) and timing of onset of circumferential contraction at the LVLP. CMR DENSE, late gadolinium enhancement, and electrical timing together could improve upon other imaging modalities for evaluating the optimal LVLP. METHODS Patients had complete CMR studies and echocardiography before CRT. CRT response was defined as a 15% reduction in left ventricular end-systolic volume. Electrical activation was assessed as the time from QRS onset to LVLP electrogram (QLV). Patients were then followed for clinical events. RESULTS In 75 patients, multivariable logistic modeling accurately identified the 40 patients (53%) with CRT response (area under the curve: 0.95 [p < 0.0001]) based on CURE (odds ratio [OR]: 2.59/0.1 decrease), delayed circumferential contraction onset at LVLP (OR: 6.55), absent LVLP scar (OR: 14.9), and QLV (OR: 1.31/10 ms increase). The 33% of patients with CURE <0.70, absence of LVLP scar, and delayed LVLP contraction onset had a 100% response rate, whereas those with CURE ≥0.70 had a 0% CRT response rate and a 12-fold increased risk of death; the remaining patients had a mixed response profile. CONCLUSIONS Mechanical, electrical, and scar properties at the LVLP together with CMR mechanical dyssynchrony are strongly associated with echocardiographic CRT response and clinical events after CRT. Modeling these findings holds promise for improving CRT outcomes.

Magnetic Resonance Imaging of Carotid Atherosclerotic Plaque in Clinically Suspected Acute Transient Ischemic Attack and Acute Ischemic Stroke

Background— Carotid atherosclerotic plaque rupture is thought to cause transient ischemic attack (TIA) and ischemic stroke (IS). Pathological hallmarks of these plaques have been identified through observational studies. Although generally accepted, the relationship between cerebral thromboembolism and in situ atherosclerotic plaque morphology has never been directly observed noninvasively in the acute setting. Methods and Results— Consecutive acutely symptomatic patients referred for stroke protocol magnetic resonance imaging/angiography underwent additional T1- and T2-weighted carotid bifurcation imaging with the use of a 3-dimensional technique with blood signal suppression. Two blinded reviewers performed plaque gradings according to the American Heart Association classification system. Discharge outcomes and brain magnetic resonance imaging results were obtained. Image quality for plaque characterization was adequate in 86 of 106 patients (81%). Eight TIA/IS patients with noncarotid pathogenesis were excluded, yielding 78 study patients (38 men and 40 women with a mean age of 64.3 years, SD 14.7) with 156 paired watershed vessel/cerebral hemisphere observations. Thirty-seven patients had 40 TIA/IS events. There was a significant association between type VI plaque (demonstrating cap rupture, hemorrhage, and/or thrombosis) and ipsilateral TIA/IS (P<0.001). A multiple logistic regression model including standard Framingham risk factors and type VI plaque was constructed. Type VI plaque was the dominant outcome-associated observation achieving significance (P<0.0001; odds ratio, 11.66; 95% confidence interval, 5.31 to 25.60). Conclusions— In situ type VI carotid bifurcation region plaque identified by magnetic resonance imaging is associated with ipsilateral acute TIA/IS as an independent identifier of events, thereby supporting the dominant disease pathophysiology.

Superiority of moderate control of hyperglycemia to tight control in patients undergoing coronary artery bypass grafting

OBJECTIVE Although consensus in cardiac surgery supports tight control of perioperative hyperglycemia (glucose<120 mg/dL), recent studies in critical care suggest moderate glycemic control may be superior. We sought to determine whether tight control or moderate glycemic control is optimal after coronary artery bypass grafting. METHODS From 1995 to 2008, a total of 4658 patients with known diabetes or perioperative hyperglycemia (preoperative glycosylated hemoglobin≥8 or postoperative serum glucose>126 mg/dL) underwent isolated coronary artery bypass grafting at our institution. Patients were stratified into 3 postoperative glycemic groups: tight (≤126 mg/dL), moderate (127-179 mg/dL), and liberal (≥180 mg/dL). Preoperative risk factors, glycemic management, and postoperative outcomes were analyzed. RESULTS Operative mortality was 2.5% (119/4658); major complication rate was 12.5% (581/4658). Relative to moderate group, more patients in tight group had preoperative renal failure (tight 16.4%, 22/134, moderate 8.3%, 232/2785, P=.001) and underwent emergent operations (tight 5.2%, 7/134, moderate 1.9%, 52/2785, P=.007); however, Society of Thoracic Surgeons predicted mortality risk was lower in tight group (P<.001). Moderate group had lowest mortality (tight 2.9%, 4/134, moderate 2.0%, 56/2785, liberal 3.4%, 59/1739, P=.02) and incidence of major complications (tight 19.4%, 26/134, moderate 11.1%, 308/2785, liberate 14.2%, 247/1739, P<.001). Risk-adjusted major complication incidence (adjusted odds ratio 0.7, 95% confidence interval 0.58-0.87) and mortality (adjusted odds ratio 0.6, 95% confidence interval 0.37-0.83) were lower with moderate glucose control than with tight or liberal management. CONCLUSIONS Moderate glycemic control was superior to tight glycemic control, with decreased mortality and major complications, and may be ideal for patients undergoing isolated coronary artery bypass grafting.

The association between hospital characteristics and rates of preventable complications and adverse events.

Background/Objectives:This study examined the statistical relationship between hospital ownership and teaching status and hospital rates for potentially preventable adverse events measured using patient safety indicators recently developed by the Agency for Healthcare Research and Quality. Research Design/Measures:A nationally representative sample of hospitals grouped into mutually exclusive combinations of control/ownership, teaching status, and rurality was defined using the Nationwide Inpatient Sample data set for the year 2000. Hospital rates for 5 categories of preventable adverse events were measured in 3 forms: unadjusted, risk-adjusted, and risk-adjusted ratios with smoothing. Multivariable regression analysis was used to measure the statistical significance of the relationship between hospital type and rates for potentially preventable adverse events, with adjustments for differences in hospital bed size and region. Results:This analysis found an inconsistent relationship between categories of hospital type and quality care measured by alternative indicators of potentially preventable conditions. Conclusions:Hospital ownership and teaching status is not a consistent predictor of differences in rates of potentially preventable adverse events, and these characteristics explain little of the observed variation in the rates of these events across hospitals.