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Jeffrey H Silber

Publications and source records attributed to Jeffrey H Silber.

16 recordsLinked to original sources
PubMed2005

Role of afterload reduction in the prevention of late anthracycline cardiomyopathy.

Afterload reduction is useful for treating and preventing adult congestive heart failure outside the realm of anthracycline toxicity. Afterload reducers are commonly used as treatment for acute heart failure associated with anthracyclines. However, the use of afterload reduction for the prevention of anthracycline associated late cardiomyopathy remains a controversial area, with strong opinions expressed concerning the potential risks and benefits of such an approach. This article will define "afterload" and the tools utilized to measure afterload. The study will then describe the theory for the use of afterload reduction in patients with anthracycline exposure who show signs of anthracycline cardiotoxicity, and will present data from the ACE-Inhibitor After Anthracyclines (AAA) Trial to help answer the question, "Should an afterload reducer be used to aid in preventing late anthracycline cardiotoxicity?" Finally, recommendations for future research will be presented.

Angiotensin-Converting Enzyme Inhibitors↗
PubMed2005

Changes in prognosis after the first postoperative complication.

BACKGROUND: Postoperative complications are common in the Medicare population, yet no study has formally quantified the change in prognosis that occurs after a broad range of first complications. OBJECTIVE: We sought to estimate the relative severity of 24 first postoperative complications. RESEARCH DESIGN: We undertook a multivariate matched, population-based, case-control study of death after surgery in a sample of 1362 Pennsylvania Medicare patients. SUBJECTS: Cases (681 deaths) were selected randomly using claims from 1995-1996. Models were developed to scan all Pennsylvania claims, looking for similar controls that did not die. MEASURES: Charts were abstracted, complications identified, and models were constructed to estimate the odds of dying after any 1 of 24 first postoperative complications. RESULTS: The odds of dying within 60 days increased 3.4-fold (95% confidence interval [CI] 2.5-4.7) in patients with complications as compared with those without complications. A first complication of respiratory compromise was associated with a 7.2-fold increase in the odds of dying (95% CI 4.5-11.6). The first complications of pneumonia or congestive heart failure were associated with, respectively, 5-fold (95% CI 2.1-12.1) and 5.1-fold (2.3-11.1) increases in odds of dying as compared with no complication. CONCLUSIONS: First complications after surgery, even seemingly mild ones, may radically alter the patient's risk of death. First complications often begin the cascade of complications that end in death. Caregivers should consider the first complication as a timely signal of a changed clinical situation demanding a reevaluation of the patient's care. Researchers may use these estimates to determine the relative severity of a broad range of first or early complications.

Aged↗
PubMed2004

Using health-related quality of life measures to predict cardiac function in survivors exposed to anthracyclines.

PURPOSE: As the number of pediatric cancer survivors increases, so does the number of survivors previously exposed to anthracyclines as part of their cancer therapy. Because screening is costly, some have suggested that health-related quality of life (HRQL) measures might be useful in focusing screening tests on those patients with cases most likely to display positive findings. This study reports on the predictive ability of HRQL measures to detect patients with abnormalities on serial cardiac testing. METHODS: Using 127 patients from the ACE-Inhibitor after Anthracycline (AAA) Trial, this study compared serial measures of the Short Form-36 (SF-36; for ages > 13 years) and Child Health Questionnaire-Child Form 87 (CHQ-CF87; for ages < or = 13 years) to serial cardiac performance tests including echocardiographic shortening fraction, left ventricular end systolic wall stress (LVESWS), LVESWS-index, and maximal cardiac index (MCI; a measure of cardiac output at peak exercise). RESULTS: Generally, there was no clinically or statistically significant correlation between any HRQL measure and any cardiac function measure except between MCI and vitality and physical functioning. For each of these measures, the correlation between MCI was statistically significant (P < .006), but each HRQL subscale could explain no more than 7% of the variation in MCI. HRQL measures were not predictive of any other cardiac function measure. CONCLUSION: HRQL measures should not be used in isolation as a screen for cardiac function abnormalities in patients exposed to anthracylines who already have a mild degree of ventricular dysfunction. Patient history appears to be no substitute for cardiac testing in this cohort.

Adolescent↗
PubMed2004

Enalapril to prevent cardiac function decline in long-term survivors of pediatric cancer exposed to anthracyclines.

PURPOSE: To determine whether an angiotensin-converting enzyme (ACE) inhibitor, enalapril, prevents cardiac function deterioration (defined using maximal cardiac index [MCI] on exercise testing or increase in left ventricular end-systolic wall stress [LVESWS]) in long-term survivors of pediatric cancer. PATIENTS AND METHODS: This was a randomized, double-blind, controlled clinical trial comparing enalapril to placebo in 135 long-term survivors of pediatric cancer who had at least one cardiac abnormality identified at any time after anthracycline exposure. RESULTS: There was no difference in the rate of change in MCI per year between enalapril and placebo groups (0.30 v 0.18 L/min/m(2); P =.55). However, during the first year of treatment, the rate of change in LVESWS was greater in the enalapril group than in the placebo group (-8.59 v 1.85 g/cm(2); P =.033) and this difference was maintained over the study period, resulting in a 9% reduction in estimated LVESWS by year 5 in the enalapril group. Six of seven patients removed from random assignment to treatment because of cardiac deterioration were initially treated with placebo (P =.11), and one has died as a result of heart failure. Side effects from enalapril included dizziness or hypotension (22% v 3% in the placebo group; P =.0003) and fatigue (10% v 0%; P =.013). CONCLUSION: Enalapril treatment did not influence exercise performance, but did reduce LVESWS in the first year; this reduction was maintained over the study period. Any theoretical benefits of LVESWS reduction in this anthracycline-exposed population must be weighed against potential side effects from ACE inhibitors when making treatment decisions.

Adolescent↗
PubMed2004

Optimal multivariate matching before randomization.

Although blocking or pairing before randomization is a basic principle of experimental design, the principle is almost invariably applied to at most one or two blocking variables. Here, we discuss the use of optimal multivariate matching prior to randomization to improve covariate balance for many variables at the same time, presenting an algorithm and a case-study of its performance. The method is useful when all subjects, or large groups of subjects, are randomized at the same time. Optimal matching divides a single group of 2n subjects into n pairs to minimize covariate differences within pairs-the so-called nonbipartite matching problem-then one subject in each pair is picked at random for treatment, the other being assigned to control. Using the baseline covariate data for 132 patients from an actual, unmatched, randomized experiment, we construct 66 pairs matching for 14 covariates. We then create 10000 unmatched and 10000 matched randomized experiments by repeatedly randomizing the 132 patients, and compare the covariate balance with and without matching. By every measure, every one of the 14 covariates was substantially better balanced when randomization was performed within matched pairs. Even after covariance adjustment for chance imbalances in the 14 covariates, matched randomizations provided more accurate estimates than unmatched randomizations, the increase in accuracy being equivalent to, on average, a 7% increase in sample size. In randomization tests of no treatment effect, matched randomizations using the signed rank test had substantially higher power than unmatched randomizations using the rank sum test, even when only 2 of 14 covariates were relevant to a simulated response. Unmatched randomizations experienced rare disasters which were consistently avoided by matched randomizations.

Adult↗
PubMed2004

The 2004 Marshall Urist award: delays until surgery after hip fracture increases mortality.

The objective of this study was to analyze whether a delay in time from admission until surgical treatment increased the mortality rate for patients with a closed hip fracture. We used the day of the week of admission as an instrumental variable to pseudorandomize patients. We analyzed 18,209 Medicare recipients who were 65 years of age or older and had surgical treatment for a closed hip fracture. Patients for whom the delay between admission and surgery was 2 days or more had a 17% higher chance of dying by Day 30. Using instrumental variables analysis, we found a similar 15% increased risk of mortality in patients with delays until surgery of 2 or more days. Based on these results, we found that a delay of 2 or more days significantly increased the mortality rate. This suggests that delay to surgery independently affects mortality, therefore additional study on the effect of smaller delays on outcome is needed.

Aged↗
PubMed2004

Do regulations limiting residents' work hours affect patient mortality?

OBJECTIVE: To conduct a statewide analysis of the effect of New York's regulations, limiting internal medicine and family practice residents' work hours, on patient mortality. DESIGN: Retrospective study of inpatient discharge files for 1988 (before the regulations) and 1991 (after the regulations). SETTING AND PATIENTS: Adult patients discharged from New York teaching hospitals (170214) and nonteaching hospitals (143,455) with a principal diagnosis of congestive heart failure, acute myocardial infarction, or pneumonia, for the years 1988 and 1991 (periods before and after Code 405 regulations went into law). Patients from nonteaching hospitals served as controls. MEASUREMENT: In-hospital mortality. RESULTS: Combined unadjusted mortality for congestive heart failure, acute myocardial infarction, and pneumonia patients declined between 1988 and 1991 in both teaching (14.1% to 13.0%; P =.0001) and nonteaching hospitals (14.0% to 12.5%; P =.0001). Adjusted mortality also declined between 1988 and 1991 in both teaching (odds ratio [OR], death 1991/1988, 0.868; 95% confidence interval [CI], 0.843 to 0.894; P =.0001) and nonteaching hospitals (OR, death 1991/1988, 0.853; 95% CI, 0.826 to 0.881; P =.0001). This beneficial trend toward lower mortality over time was nearly identical between teaching and nonteaching hospitals (P =.4348). CONCLUSION: New York's mandated limitations on residents' work hours do not appear to have positively or negatively affected in-hospital mortality from congestive heart failure, acute myocardial infarction, or pneumonia in teaching hospitals.

Confidence Intervals↗
PubMed2004

Equivalent lengths of stay of pediatric patients hospitalized in rural and nonrural hospitals.

BACKGROUND: Many children receive their care at local hospitals outside of a large urban area. There may be differences in the length of stay (LOS) between children hospitalized in rural versus urban hospitals. This study compared the differences in LOS, conditional LOS (CLOS), odds of prolonged stay, and 21-day readmission rates for children with 19 medical conditions and 9 surgical procedures admitted to rural, community, and large urban hospitals. METHODS: Discharge records for the hospitalizations of children 1 to 17 years of age were obtained from the New York Department of Public Health Statewide Planning and Research Cooperative System and the Pennsylvania Health Care Cost Containment Council for April 1996 to July 1998. The 19 medical and 9 surgical conditions were identified with the principal condition and procedure codes. Hospitals were classified into 1 of 5 geographic categories on the basis of United States rural-urban continuum codes, ie, large urban, suburban, moderate urban, small urban, or rural. LOS was defined as the period of time between hospital admission and discharge. Readmission rates were calculated for 21 days after discharge from the hospital. A prolonged stay for each condition was defined as any admission lasting beyond the prolongation point, or the day at which the rate of discharge began to decline, as determined with the Hollander-Proschan statistic. This aspect of LOS describes the ability of providers to treat uncomplicated cases of that specific principle diagnosis. CLOS, as a marker for the management of complicated cases, was defined as the LOS beyond the prolongation point. Cox and logistic regression models were developed to describe the geographic effects on the 4 outcome variables, after severity adjustment with 32 demographic and 11 comorbidity variables and adjustment for hospital clustering. RESULTS: Medical (N = 114,787) and surgical (N = 29,156) admissions to rural hospitals (N = 12,367) had similar outcomes, compared with all geographic categories except the large urban category. Medical patients admitted to rural hospitals had a shorter LOS (12% increase in discharge rate), a shorter CLOS (12% increase in discharge rate), and lower odds of prolonged stay (odds ratio: 0.80), compared with those in large urban hospitals. Surgical patients admitted to rural hospitals had a shorter LOS (12% increase in discharge rate) and lower odds of prolonged stay (odds ratio: 0.81), compared with those in large urban hospitals. For individual conditions, rural hospitals in general had similar or improved LOS, compared with all other hospitals in the 2 states. The addition of hospital-level variables failed to change the results of the primary models. CONCLUSIONS: In their treatment of pediatric hospitalized patients, rural hospitals were not significantly different from hospitals in all geographic regions other than large urban areas. Rural hospitals appear to deliver similar care, compared with nonrural hospitals, for many of the common pediatric conditions included in this study. Additional research is needed to apply these results to other regions or states with different geographic distributions of hospitals and children, in order to determine the overall impact on the regionalization of pediatric care.

Adolescent↗
PubMed2003

Educational levels of hospital nurses and surgical patient mortality.

CONTEXT: Growing evidence suggests that nurse staffing affects the quality of care in hospitals, but little is known about whether the educational composition of registered nurses (RNs) in hospitals is related to patient outcomes. OBJECTIVE: To examine whether the proportion of hospital RNs educated at the baccalaureate level or higher is associated with risk-adjusted mortality and failure to rescue (deaths in surgical patients with serious complications). DESIGN, SETTING, AND POPULATION: Cross-sectional analyses of outcomes data for 232 342 general, orthopedic, and vascular surgery patients discharged from 168 nonfederal adult general Pennsylvania hospitals between April 1, 1998, and November 30, 1999, linked to administrative and survey data providing information on educational composition, staffing, and other characteristics. MAIN OUTCOME MEASURES: Risk-adjusted patient mortality and failure to rescue within 30 days of admission associated with nurse educational level. RESULTS: The proportion of hospital RNs holding a bachelor's degree or higher ranged from 0% to 77% across the hospitals. After adjusting for patient characteristics and hospital structural characteristics (size, teaching status, level of technology), as well as for nurse staffing, nurse experience, and whether the patient's surgeon was board certified, a 10% increase in the proportion of nurses holding a bachelor's degree was associated with a 5% decrease in both the likelihood of patients dying within 30 days of admission and the odds of failure to rescue (odds ratio, 0.95; 95% confidence interval, 0.91-0.99 in both cases). CONCLUSION: In hospitals with higher proportions of nurses educated at the baccalaureate level or higher, surgical patients experienced lower mortality and failure-to-rescue rates.

Cross-Sectional Studies↗
PubMed2003

Market reform in New Jersey and the effect on mortality from acute myocardial infarction.

OBJECTIVE: To determine whether mortality rates for patients with acute myocardial infarction (AMI) changed in New Jersey after implementation of the Health Care Reform Act, which reduced subsidies for hospital care for the uninsured and changed hospital payment to price competition from a rate-setting system based on hospital cost. DATA SOURCES/STUDY SETTING: Patient discharge data from hospitals in New Jersey and New York from 1990 through 1996 and the Healthcare Cost and Utilization Project (HCUP) Nationwide Inpatient Sample (NIS). STUDY DESIGN: A comparison between states over time of unadjusted and risk-adjusted mortality and cardiac procedure rates. DATA COLLECTION: Discharge data were obtained for 286,640 patients with the primary diagnosis of AMI admitted to hospitals in New Jersey or New York from 1990 through 1996. Records of 364,273 NIS patients were used to corroborate time trends. PRINCIPAL FINDINGS: There were no significant differences in AMI mortality among insured patients in New Jersey relative to New York or the NIS. However, there was a relative increase in mortality of 41 to 57 percent among uninsured New Jersey patients post-reform, and their rates of expensive cardiac procedures decreased concomitantly. CONCLUSIONS: The introduction of hospital price competition and reductions in subsidies for hospital care of the uninsured were associated with an increased mortality rate among uninsured New Jersey AMI patients. A relative decrease in the use of cardiac procedures in New Jersey may partly explain this finding. Additional studies should be done to identify whether other market reforms have been associated with changes in the quality of care.

Adult↗
PubMed2003

Length of stay, conditional length of stay, and prolonged stay in pediatric asthma.

OBJECTIVE: To understand differences in length of stay for asthma patients between New York State and Pennsylvania across children's and general hospitals in order to better guide policy. DATA SOURCES/STUDY SETTING: All pediatric admissions for asthma in the states of Pennsylvania and New York using claims data obtained from each state for the years 1996-1998, n = 38,310. STUDY DESIGN: A retrospective cohort design to model length of stay (LOS), the probability of prolonged stay, conditional length of stay (CLOS or the LOS after stay is prolonged), and the probability of readmission, controlling for patient factors, state, location and hospital type. ANALYTIC METHODS: Logit models were used to estimate the probability of prolonged stay and readmission. The LOS and the CLOS were estimated with Cox regression. Model variables included comorbidities, income, race, distance from hospital, and insurance type. Prolonged stay was based on a Hollander-Proschan "New-Worse-Than-Used" test, corresponding to a three-day stay. PRINCIPAL FINDINGS: The LOS was longer in New York than Pennsylvania, and the probabilities of prolonged stay and readmission were much higher in New York than Pennsylvania. However, once an admission was prolonged, there were no differences in CLOS between states (when readmissions were not added to the LOS calculation). In both states, children's hospitals and general hospitals had similar adjusted LOS. CONCLUSIONS: Management of asthma appears more efficient in Pennsylvania than New York: Less severe patients are discharged faster in Pennsylvania than New York; once discharged, patients are less likely to be readmitted in Pennsylvania than New York. However, once a stay is prolonged, there is little difference between New York and Pennsylvania, suggesting medical care for severely ill patients is similar across states. Differences between children's and general hospitals were small as compared to differences between states. We conclude that policy initiatives in New York, and other states, should focus their efforts on improving the care provided to less severe patients in order to help reduce overall length of stay.

Adolescent↗
PubMed2003

Hospital nurse staffing, education, and patient mortality.

A serious shortage of hospital nurses in the U.S., evident in the past decade, is expected to continue and worsen in the next 15 years. Increasingly, the public and the health professions are acknowledging that nurse understaffing represents a serious threat to patient safety in U.S. hospitals. Although anecdotal evidence has linked patient deaths to inadequate nurse staffing, the numbers and kinds of nurses needed for patient safety is unknown. This Issue Brief highlights two studies that clarify the impact of nurse staffing levels on surgical patient outcomes, and examine the effect of nurses' experience and educational level on patient mortality in the 30 days after a surgical admission.

Educational Status↗
PubMed2002

Anesthesiologist board certification and patient outcomes.

BACKGROUND: Board certification is often used as a surrogate indicator of provider competence, although few outcome studies have demonstrated its validity. The aim of this study was to compare the outcomes of patients who underwent surgical procedures under the care of an anesthesiologist with or without board certification. METHODS: Medicare claims records for 144,883 patients in Pennsylvania who underwent general surgical or orthopedic procedures between 1991 and 1994 were used to determine provider-specific outcome rates adjusted to account for patient severity and case mix, and hospital characteristics. Outcomes of 8,894 cases involving midcareer anesthesiologists, 11-25 yr from medical school graduation, who lacked board certification were compared with all other cases. Midcareer anesthesiologist cases were studied because this group had sufficient time to become certified during an era when obtaining certification was already considered important, and consequently had the highest rate of board certification. Mortality within 30 days of admission and the failure-to-rescue rate (defined as the rate of death after an in-hospital complication) were the two primary outcome measures. RESULTS: Adjusted odds ratios for death and failure to rescue were greater when care was delivered by noncertified midcareer anesthesiologists (death = 1.13 [95% confidence interval, 1.00, 1.26], P < 0.04; failure to rescue = 1.13 [95% confidence interval, 1.01, 1.27], P < 0.04). Adjusting for international medical school graduates did not change these results. CONCLUSIONS: When anesthesiology board certification is very common, as in midcareer practitioners, the lack of board certification is associated with worse outcomes. However, the poor outcomes associated with noncertified providers may be a result of the hospitals at which they practice and not necessarily their manner of practice.

Adult↗
PubMedDate not supplied

Hospital nurse staffing and patient mortality, nurse burnout, and job dissatisfaction.

CONTEXT: The worsening hospital nurse shortage and recent California legislation mandating minimum hospital patient-to-nurse ratios demand an understanding of how nurse staffing levels affect patient outcomes and nurse retention in hospital practice. OBJECTIVE: To determine the association between the patient-to-nurse ratio and patient mortality, failure-to-rescue (deaths following complications) among surgical patients, and factors related to nurse retention. DESIGN, SETTING, AND PARTICIPANTS: Cross-sectional analyses of linked data from 10 184 staff nurses surveyed, 232 342 general, orthopedic, and vascular surgery patients discharged from the hospital between April 1, 1998, and November 30, 1999, and administrative data from 168 nonfederal adult general hospitals in Pennsylvania. MAIN OUTCOME MEASURES: Risk-adjusted patient mortality and failure-to-rescue within 30 days of admission, and nurse-reported job dissatisfaction and job-related burnout. RESULTS: After adjusting for patient and hospital characteristics (size, teaching status, and technology), each additional patient per nurse was associated with a 7% (odds ratio [OR], 1.07; 95% confidence interval [CI], 1.03-1.12) increase in the likelihood of dying within 30 days of admission and a 7% (OR, 1.07; 95% CI, 1.02-1.11) increase in the odds of failure-to-rescue. After adjusting for nurse and hospital characteristics, each additional patient per nurse was associated with a 23% (OR, 1.23; 95% CI, 1.13-1.34) increase in the odds of burnout and a 15% (OR, 1.15; 95% CI, 1.07-1.25) increase in the odds of job dissatisfaction. CONCLUSIONS: In hospitals with high patient-to-nurse ratios, surgical patients experience higher risk-adjusted 30-day mortality and failure-to-rescue rates, and nurses are more likely to experience burnout and job dissatisfaction.

Adult↗