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Mark Weiner

Publications and source records attributed to Mark Weiner.

10 recordsLinked to original sources
PubMed2006

Characteristics of patients undergoing atrial fibrillation ablation: trends over a seven-year period 1999-2005.

BACKGROUND: Catheter ablation procedures for treating atrial fibrillation (AF) have dramatically increased since triggers of AF were first described in 1998. OBJECTIVE: We explored changes in patient characteristics in patients referred for catheter ablation of AF over a seven-year period from 1999 through 2005. METHODS: Patient characteristics were examined for all patients undergoing AF ablation from 1999 through 2005 at the University of Pennsylvania Health System (UPHS). The gender of patients undergoing ablation was also compared with outpatients seen at UPHS with a primary diagnosis of AF. RESULTS: From 1999 to 2005 the number of patients undergoing ablation has increased steadily, from 29 patients in 1999 to 265 patients in 2005 (P < 0.01). Patients have become older (47 to 56 years; P < 0.01), with more persistent or permanent AF (17% to 45%; P < 0.01), larger left atrial size (4.0 to 4.4 cm; P < 0.01), and fewer antiarrhythmic drugs used prior to ablation (3.9 to 2.0 drugs; P < 0.01). Patients undergoing ablation have been predominantly male, with a significantly higher male prevalence than patients seen in the UPHS outpatient primary care clinic with AF (77% vs 59% male; P < 0.001). CONCLUSIONS: Patients undergoing AF ablation from 1999 to 2005 are older, with larger left atrial size, more persistent/permanent AF, and fewer prior antiarrhythmic agents used. Compared with the gender-specific rates of AF in the population, the majority of patients referred for ablation are men, suggesting a referral bias against this invasive procedure for women. These findings are important for interpreting the outcome of ablation in the current era, and for designing prospective randomized trials.

Aged↗
PubMed2005

The financial burden of emergency department congestion and hospital crowding for chest pain patients awaiting admission.

STUDY OBJECTIVE: We determined the additional cost of an extended emergency department (ED) length of stay for chest pain patients awaiting non-ICU, monitored (telemetry) beds. METHODS: This was a prospective cohort study of all ED chest pain patients aged 24 years or older and admitted to a telemetry bed in an urban university hospital during a 12-month period. Structured ED data collection included demographics, chest pain presentation, medical history, and laboratory test and ECG results. Hospital course was monitored daily, followed by a 30-day telephone follow-up. Risk severity scores (Goldman, Acute Cardiac Ischemia-Time-Insensitive Predictive Instrument, and Charlson) were calculated. Hospital charges, real costs, and revenues were obtained at discharge and 2 years later. The main outcome measure was risk-adjusted additional cost to the hospital of a delayed ED admission. Clinical outcome was a secondary measure. RESULTS: Of the 817 patients with chest pain presenting to the ED during the study period, there were 904 hospitalizations. Of these, 825 patients waited more than 3 hours for their bed (91%). There were 21 patient visits with a final diagnosis of acute myocardial infarction. ED length of stay was not associated with total hospital length of stay (r =0.01), hospital costs, or hospital or professional charges, revenues, or collection rates. The annual opportunity cost in lost hospital revenue for chest pain patients was 168,300 US dollars (204 US dollars per patient waiting >3 hours for a hospital bed). CONCLUSION: Extended ED length of stay demonstrated no association with total hospital costs or revenues or total hospital length of stay but imposed substantial ED opportunity costs, with decreased potential revenue. Interventions that reduce ED delays in hospital admissions have the potential to significantly increase hospital revenues.

Adult↗
PubMed2005

Seasonal variation in undiagnosed HIV infection on the general medicine and trauma services of two urban hospitals.

OBJECTIVE: To examine the seroprevalence of undiagnosed HIV and variation by season among patients admitted to the general internal medicine (GIM) and trauma services of two urban hospitals. DESIGN: A cross-sectional blinded HIV-1 seroprevalence survey. SETTING: A 725-bed academic medical center's hospital and an affiliated 324-bed tertiary care hospital. PARTICIPANTS: Residual serological specimens were obtained for unique patients aged 17 to 65 to study services in summer (June 16 to September 4, 2001) and fall to winter (November 1, 2001 to January 8, 2002). METHODS: Hospital files provided data on demographics, service type, and discharge clinical categories (fall-winter group only). HIV ELISA (enzyme-linked immunosorbent assay) tests with confirmatory Western blot were linked to subjects' de-identified files. We excluded 34 subjects with known HIV. Of the remaining unique admissions in summer (n=604) and fall-winter (n=978), 60% and 55% were tested, respectively. Predictors of undiagnosed HIV infection were examined using multivariate analysis. RESULTS: The summer cohort (n=362) had significantly lower unadjusted seroprevalence of undiagnosed HIV infection (1.4%; 95% confidence interval [CI], 0.4% to 3.2%) than the fall-winter cohort (n=539; 3.7%; 95% CI, 2.3% to 5.7%; P=.04). Overall, undiagnosed HIV was somewhat less likely in women (adjusted odds ratio [AOR], 0.45; 95% CI, 0.19 to 1.07) but more likely in black patients (AOR, 3.46; 95% CI, 0.70 to 17.06). In the fall-winter cohort, undiagnosed HIV was more likely for discharges with the following clinical categories versus those with a cardiac condition: dermatologic/breast (AOR, 14.90; 95% CI, 1.20 to 184.77), renal/urological (AOR, 22.43; 95% CI, 2.12 to 236.75), or infectious (AOR, 31.08; 95% CI, 2.40 to 402.98). CONCLUSIONS: The higher seroprevalence of undiagnosed HIV in the fall-winter admissions to GIM and trauma services supports especially targeting HIV testing in these months.

Adolescent↗
PubMed2004

Predicting adherence to colonoscopy or flexible sigmoidoscopy on the basis of physician appointment-keeping behavior.

BACKGROUND: Poor patient attendance to scheduled flexible sigmoidoscopy or colonoscopy may contribute to deficient colorectal cancer screening. OBJECTIVE: To examine the association of physician appointment-keeping behavior with attendance to scheduled endoscopic studies of the colon. DESIGN: Retrospective cohort. SETTING: 23 sites performing endoscopic procedures in a health care system. PATIENTS: 11 803 patients scheduled for a first colon study with 3 or more scheduled physician visits from June 1999 through November 2001. MEASUREMENT: 2 outcomes from health system computerized records: 1) attendance at the first scheduled colon study and 2) among nonattendees, attendance at the study rescheduled within 6 months. Physician visit adherence was defined as the proportion of physician visits kept, grouped by quartile. Adjusted associations were examined in conditional logistic regression. RESULTS: Of 11 803 patients, 62% attended the first colon study. Of the 4496 nonattendees, 2739 (61%) rescheduled and, of these, 64% kept that appointment. Compared with the highest quartile of physician visit adherence (>85%), the adjusted odds ratio of attending the first colon study decreased as physician visit adherence decreased: Adjusted odds ratios were 0.94 (95% CI, 0.89 to 1.00) for 76% to 85% adherence, 0.87 (CI, 0.81 to 0.92) for 66% to 75% adherence, and 0.79 (CI, 0.73 to 0.85) for adherence of 65% or less. Among nonattendees who rescheduled, the lowest quartile of physician visit adherence (< or =65%) was the only statistically significant predictor of attending the rescheduled study (adjusted odds ratio, 0.87 [CI, 0.78 to 0.98]). LIMITATIONS: The adherence measure applies only to patients with at least 3 scheduled visits. Persons having a colon study outside of the system could have been misclassified. CONCLUSION: Physician appointment-keeping behavior predicted attendance to colorectal endoscopic studies in this cohort and may help identify persons who need interventions to promote adherence.

Aged↗
PubMed2004

Cross-sectional versus longitudinal performance assessments in the management of diabetes.

BACKGROUND: Performance assessments help to quantify the level of adherence with practice standards and are often used to measure and compare the quality of care. However, most performance assessments are based on a cross-sectional analysis of patient information, whereas patient care is inherently longitudinal. This discordance could confound the relationship between the performance measure and the true quality of care. OBJECTIVE: The objective of this study was to illustrate differences in performance assessment as measured by a traditional cross-sectional analysis compared with a longitudinal analysis. METHODS: We conducted a cross-sectional and longitudinal analysis of a cohort of diabetic patients in an integrated delivery system having primary care visits and hemoglobin A1c (HBA1c) testing in both 1999 and 2000. RESULTS: In the cross-sectional analysis of 4661 patients, we found a modestly increasing proportion achieved an HBA1c level of <8.0%: 73.1% in 1999 and 75.6% in 2000. Longitudinal analysis, however, suggested that certain subsets of patients were more likely to switch from good to poor control or retain their level of poor control over the 2 years studied. In particular, compared with whites, blacks were 1.76 (95% confidence interval [CI], 1.31-2.37) times as likely to switch from good to poor control and only 0.56 (95% CI, 0.41-0.76) times as likely to switch from poor to good control. Patients aged 35 to 49 were 2.54 (95% CI, 1.79-3.45) times as likely to switch from good to poor and only 0.66 (95% CI, 0.47-0.94) times as likely to switch from poor to good control than patients over age 64 years. CONCLUSIONS: Cross-sectional performance assessments could mask changes in diabetes control among individuals belonging to a cohort and, conceptually, are poorer indicators of care process than longitudinal measures. In addition, longitudinal analyses suggest the influence of patient sociodemographic factors on the performance assessment that should be accounted for when comparing quality of care for diabetes.

Age Factors↗
PubMed2003

High- versus low-dose angiotensin converting enzyme inhibitor therapy in the treatment of heart failure: an economic analysis of the Assessment of Treatment with Lisinopril and Survival (ATLAS) trial.

BACKGROUND: Angiotensin-converting enzyme (ACE) inhibitors reduce heart failure death and hospitalization. Prescribed doses often are lower than randomized clinical trial (RCT) targets and practice guideline recommendations. OBJECTIVE: To assess the cost-effectiveness of high- versus low-dose ACE inhibitor therapy in the ATLAS trial. STUDY DESIGN: A 19-nation RCT of high-dose (32.5-35.0 mg/day) versus low-dose (2.5-5.0 mg/day) lisinopril in 3164 patients with class II-IV heart failure and left ventricular ejection fraction < or = 30%. METHODS: Data on clinical outcomes and major cost events (hospitalizations and drug utilization) were collected prospectively. Hospital costs were estimated using Medicare and representative managed care diagnosis-related group reimbursement rates. ACE inhibitor drug costs were estimated using US average wholesale prices. Costs were discounted at 3% annually. RESULTS: Patients in the high-dose lisinopril group had fewer hospitalizations (1.98 vs 2.22, P = .014) and hospital days (18.28 vs 22.22, P = .002), especially heart failure hospitalizations (0.64 vs 0.80, P = .006) and heart failure hospital days (6.02 vs 7.45, P = .028) compared with the low-dose group. The high-dose lisinopril group also had lower heart failure hospital costs (dollars 5114 vs dollars 6361, P = .006) but higher ACE inhibitor drug costs (dollars 1368 vs dollars 855, P = .0001). Total hospital and drug costs were similar between high- and low-dose lisinopril groups (mean difference dollars -875, 95% CI dollars -2613 to dollars 884). Sensitivity analyses confirmed these findings. CONCLUSIONS: Cost savings from fewer heart failure hospitalizations offset higher ACE inhibitor costs in the high-dose group. The improved clinical outcomes were achieved without increased treatment costs.

Aged↗
PubMed2002

Metadata tables to enable dynamic data modeling and web interface design: the SEER example.

A wealth of information addressing health status, outcomes and resource utilization is compiled and made available by various government agencies. While exploration of the data is possible using existing tools, in general, would-be users of the resources must acquire CD-ROMs or download data from the web, and upload the data into their own database. Where web interfaces exist, they are highly structured, limiting the kinds of queries that can be executed. This work develops a web-based database interface engine whose content and structure is generated through interaction with a metadata table. The result is a dynamically generated web interface that can easily accommodate changes in the underlying data model by altering the metadata table, rather than requiring changes to the interface code. This paper discusses the background and implementation of the metadata table and web-based front end and provides examples of its use with the NCI's Surveillance, Epidemiology and End-Results (SEER) database.

Databases, Factual↗
PubMedDate not supplied

Medical care cost of patients with prostate cancer.

OBJECTIVE: To analyze variations in direct medical care cost of patients with prostate across two racial groups after controlling for age, disease stage, and comorbidity. METHODS: In this retrospective cohort control study, we randomly selected 120 newly diagnosed prostate cancer patients (60 African Americans and 60 White) from the administrative database of a large urban academic hospital. Medical care costs data and clinical data were obtained. The control group consisted of 240 men without cancer, and matched by age and race. Demographics, clinical variables and treatment patterns were compared across race using t-test and chi2. Mean medical care costs for prostate cancer patients were compared by race, using bootstrap and log t-test. Regression models were used to estimate the incremental cost of prostate cancer, and to analyze the association between race and direct medical care cost. RESULTS: Whites were more likely to receive radical prostatectomy, whereas African Americans were more likely to receive radiation therapy. The incremental cost of prostate cancer was 1.30 times higher than controls. Charlson comorbidity was a significant predictor of type of treatment received and cost. Race was not associated with total direct medical care cost after controlling for age, Charlson comorbidity and stage of cancer at diagnosis. CONCLUSIONS: Charlson Comorbidity score was a predictor of type of treatment and direct medical care cost. While analyzing the association between race and cost of care, potential bias-inducing factors such as clinical characteristics at diagnosis and provider characteristics (physician and hospital) must be addressed.

Black or African American↗
PubMedDate not supplied

Health resource utilization and medical care cost of acute care elderly unit patients.

OBJECTIVE: In this study we compared the readmissions, medical care cost, and health resource utilization (HRU) of acute care elderly (ACE) unit patients and usual medical care patients. METHODS: Retrospective case-control design was used. Patients admitted to ACE unit (n = 680) between 1999 and 2002 with primary admitting diagnosis of pneumonia, congestive heart failure, or urinary tract infection were randomly selected from the health-care system's administrative database. Equal number controls (n = 680) were selected from usual medical care services and were matched by DRG, age, ethnicity, and Charlson comorbidity score. Data on HRU, annual number of admissions before and after index admission, length of stay (LOS), and medical care cost were obtained. Bootstrap, t-test, and Wilcoxon test were used to compare cost, LOS, and number of readmissions between ACE and non-ACE unit. Multivariate log-linear and Poisson regressions were used to assess the impact of ACE unit on incremental cost and number of readmissions, respectively. RESULTS: Mean LOS was 1 day shorter for ACE unit (4.9 vs. 5.9 P = 0.01). Mean cost of ACE unit was 9.7% lower than that of non-ACE unit (Dollars 13,586 vs. Dollars 15,040, P = 0.012). Both groups had similar costs of pharmacy, diagnostic and therapeutic procedures. Multiple log-linear and Poisson regression models indicated that ACE unit patients had 21% lower cost and 11% lower annual readmissions. CONCLUSIONS: Our results confirm the hypotheses that ACE unit patients have lower medical care cost, shorter LOS, and fewer readmissions. Thus, ACE unit may be a beneficial model for improved inpatient care of elderly.

Acute Disease↗