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Results for “Propensity Score”

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PubMed2004

Preoperative statin use and outcomes following cardiac surgery.

BACKGROUND: Cardiac surgery carries a 2-3% early mortality due in part to perioperative myocardial infarction (PMI), low-output syndrome (LOS), and arrhythmias. Statins attenuate thrombogenesis, normalize endothelial dysfunction, and mitigate the oxidative stress and reperfusion injury characteristic of such complications. We sought to determine whether preoperative statin use is associated with reduced early mortality and major morbidity following cardiac surgery. METHODS: Patients having isolated coronary artery bypass grafting (CABG), valve, or combined CABG/valve surgery between May 1998 and June 2003 (n=5469) were identified. A logistic regression model was generated to determine the association of preoperative statin use with in-hospital mortality (IHM). Propensity score analysis was used to match two subgroups of patients (Group I, on statins, n=1443; Group II, not on statins, n=1443) on multiple factors known to impact cardiac surgical outcome. Outcomes assessed were IHM, intra-aortic balloon pump (IABP) use, PMI, prolonged (>24 h) ventilation (p-vent), stroke, and a composite end point (comp) defined as any one or more of the above. RESULTS: Of the 5469 patients, 3555 were on statins and 1914 were not. Unadjusted rates of IHM (2.6% vs. 5.0%), stroke (1.9% vs. 3.3%), p-vent (10.2% vs. 16.6%), and comp (12.7% vs. 19.5%) were lower (p=0.0001) in patients receiving statins. After adjustment, statin use was not associated with a reduction in IHM (OR=0.9, 95% CI=0.6-1.2, p=0.36) or comp (OR=0.9, 95% CI=0.8-1.1, p=0.31). After matching two subgroups using propensity score for statin, no significant differences were found in any of the adjusted outcomes for Group I vs. Group II: IHM (4.0% vs. 4.6%), PMI (1.5% vs. 1.1%), p-vent (15.8% vs. 15.7%), IABP use (2.0% vs. 2.3%), stroke (3.0% vs. 3.3%), and comp (19.1% vs. 18.8%). CONCLUSIONS: Preoperative statin use is not associated with a reduction in IHM or major morbidity following cardiac surgery.

Aged↗

PubMed2005

Does preoperative coronary angioplasty improve perioperative cardiac outcome?

BACKGROUND: Percutaneous coronary intervention (PCI) is performed in patients with coronary artery disease who are undergoing major noncardiac procedures to reduce perioperative cardiac morbidity and mortality. However, the impact of this approach on postoperative outcome remains controversial. METHODS: The authors analyzed a cohort of 1,152 patients after abdominal aortic surgery in which 78 patients underwent PCI. A propensity score analysis was performed. Also, using a logistic regression model, the authors determined variables associated with a severe postoperative coronary event or a death in patients without PCI. Then, in patients with PCI, they compared the expected and observed outcome. RESULTS: Five variables (age > 75 yr, blood transfusion > 3 units, repeated surgery, preoperative hemodialysis, and previous cardiac failure) independently predicted (with 94% correctly classified) a severe postoperative coronary event, and five variables (age > 75 yr, repeated surgery, previously abnormal ST segment/T waves, previous hypertension, and previous cardiac failure) independently predicted (with 97% correctly classified) postoperative death. In the PCI group, the observed percentages of patients with a severe postoperative coronary event (9.0% [95% confidence interval, 4.4-17.4]) or death (5.1% [95% confidence interval, 2.0-12.5]) were not significantly different from the expected percentages (8.2 and 6.9%, respectively). When all patients were pooled together, the odds ratios of PCI were not significant. The propensity score analysis provided a similar conclusion. CONCLUSION: PCI did not seem to limit significantly cardiac risk or death after aortic surgery.

Aged↗

PubMed2004

Prolonged survival after complete resection of metastases from intraocular melanoma.

BACKGROUND: The median survival time is only 2-6 months after a diagnosis of metastases from intraocular melanoma. Because complete resection of metastatic melanoma from a cutaneous primary tumor can prolong survival, the authors hypothesized that resection also might benefit patients with metastases from an intraocular site. METHODS: From 1971 to 1999, 112 patients with metastatic melanoma from an intraocular site were enrolled in various treatment protocols after informed consent was obtained. Prospectively recorded clinical variables and follow-up information were retrieved from the patient database. Survival curves were estimated using the Kaplan-Meier method. Univariate analysis was performed with the log-rank test. Multivariate analysis was performed using the Cox proportional hazards regression model. Propensity score analysis was used to reduce the imbalance between subgroups and to assess treatment effect. RESULTS: Seventy-eight patients (70%) presented with liver involvement. Twenty-four patients (21%) underwent resection of metastatic lesions. At a median follow-up time of 11 months (range, 1-97 months; > 36 months for survivors), the median survival period was 11 months and the 5-year survival rate was 7%. Univariate analysis showed that surgical resection, site of metastases, number of metastatic lesions, and disease-free interval were correlated significantly with survival (P < 0.001, P < 0.001, P < 0.001, and P = 0.031, respectively). Multivariate analysis showed that surgical resection was significant (P = 0.008) but that the site of metastases was not (P = 0.146). The median survival and the 5-year survival rate were 38 months and 39%, respectively, for surgical patients, versus 9 months and 0%, respectively, for nonsurgical patients. After adjusting for covariate imbalance by propensity score analysis, surgery remained significant (P = 0.021) on multivariate analysis. CONCLUSIONS: Complete resection may prolong survival in certain patients with distant metastases from intraocular primary melanoma. However, the overall unfavorable prognosis indicates an urgent need for more effective nonsurgical interventions.

Aged↗

PubMed2006

Use and efficacy of abciximab in an unselected population with acute myocardial infarction treated with primary angioplasty: data from AMI-Florence registry.

AIMS: We sought to evaluate the determinants and the potential benefit of abciximab use in unselected patients with acute myocardial infarction treated with primary angioplasty. METHODS AND RESULTS: Based on the AMI-Florence registry, we analyzed 461 consecutive acute myocardial infarction patients treated with primary angioplasty, 280 (61%) of whom received abciximab. For each patient, a propensity score indicating the likelihood of abciximab treatment was calculated. Compared to those not treated, patients treated with abciximab were at lower risk. At multivariate analysis, the direct admission to a hospital with angioplasty facilities significantly increased the probability of receiving abciximab (OR 1.99, 95% CI 1.30-3.03, p=.001), while older age (OR 0.97, 95% CI 0.95-0.98, p<.0001), non-anterior location (OR 0.58, 95% CI 0.38-0.88, p=.011) and Killip class >1 (OR 0.53, 95% CI 0.32-0.87, p=.013), were negative predictors of abciximab use. Primary angioplasty had a higher success rate in patients treated with abciximab (99.3% versus 96.5%, p=.03). In-hospital and 1-year mortality were significantly lower in patients treated with abciximab (2.5% versus 13.3%, p<.0001, and 7% versus 21%, p<.0001, respectively). At multivariate analysis patients treated with abciximab had a significantly lower risk of in-hospital mortality (OR 0.35, 95% CI 0.14-0.93, p=.035), and a marginally lower risk of death at 1-year follow-up (HR 0.58, 95% CI 0.32-1.03, p=.065). These results did not change when the propensity score was included into the analyses. CONCLUSIONS: In the real practice, abciximab is more frequently used in patients at lower risk, particularly when directly admitted to a hospital with angioplasty facilities. Abciximab use is associated with a significant reduction in early mortality. A trend toward a reduced mortality is maintained also at 1 year.

Abciximab↗

PubMed2003

Evaluating non-randomised intervention studies.

OBJECTIVES: To consider methods and related evidence for evaluating bias in non-randomised intervention studies. DATA SOURCES: Systematic reviews and methodological papers were identified from a search of electronic databases; handsearches of key medical journals and contact with experts working in the field. New empirical studies were conducted using data from two large randomised clinical trials. METHODS: Three systematic reviews and new empirical investigations were conducted. The reviews considered, in regard to non-randomised studies, (1) the existing evidence of bias, (2) the content of quality assessment tools, (3) the ways that study quality has been assessed and addressed. (4) The empirical investigations were conducted generating non-randomised studies from two large, multicentre randomised controlled trials (RCTs) and selectively resampling trial participants according to allocated treatment, centre and period. RESULTS: In the systematic reviews, eight studies compared results of randomised and non-randomised studies across multiple interventions using meta-epidemiological techniques. A total of 194 tools were identified that could be or had been used to assess non-randomised studies. Sixty tools covered at least five of six pre-specified internal validity domains. Fourteen tools covered three of four core items of particular importance for non-randomised studies. Six tools were thought suitable for use in systematic reviews. Of 511 systematic reviews that included non-randomised studies, only 169 (33%) assessed study quality. Sixty-nine reviews investigated the impact of quality on study results in a quantitative manner. The new empirical studies estimated the bias associated with non-random allocation and found that the bias could lead to consistent over- or underestimations of treatment effects, also the bias increased variation in results for both historical and concurrent controls, owing to haphazard differences in case-mix between groups. The biases were large enough to lead studies falsely to conclude significant findings of benefit or harm. Four strategies for case-mix adjustment were evaluated: none adequately adjusted for bias in historically and concurrently controlled studies. Logistic regression on average increased bias. Propensity score methods performed better, but were not satisfactory in most situations. Detailed investigation revealed that adequate adjustment can only be achieved in the unrealistic situation when selection depends on a single factor. CONCLUSIONS: Results of non-randomised studies sometimes, but not always, differ from results of randomised studies of the same intervention. Non-randomised studies may still give seriously misleading results when treated and control groups appear similar in key prognostic factors. Standard methods of case-mix adjustment do not guarantee removal of bias. Residual confounding may be high even when good prognostic data are available, and in some situations adjusted results may appear more biased than unadjusted results. Although many quality assessment tools exist and have been used for appraising non-randomised studies, most omit key quality domains. Healthcare policies based upon non-randomised studies or systematic reviews of non-randomised studies may need re-evaluation if the uncertainty in the true evidence base was not fully appreciated when policies were made. The inability of case-mix adjustment methods to compensate for selection bias and our inability to identify non-randomised studies that are free of selection bias indicate that non-randomised studies should only be undertaken when RCTs are infeasible or unethical. Recommendations for further research include: applying the resampling methodology in other clinical areas to ascertain whether the biases described are typical; developing or refining existing quality assessment tools for non-randomised studies; investigating how quality assessments of non-randomised studies can be incorporated into reviews and the implications of individual quality features for interpretation of a review's results; examination of the reasons for the apparent failure of case-mix adjustment methods; and further evaluation of the role of the propensity score.

Bias↗

PubMed1995

Optimal case-control matching in practice.

We illustrate modern matching techniques and discuss practical issues in defining the closeness of matching for retrospective case-control designs (in which the pool of subjects already exists when the study commences). We empirically compare matching on a balancing score, analogous to the propensity score for treated/control matching, with matching on a weighted distance measure. Although both methods in principle produce balance between cases and controls in the marginal distributions of the matching covariates, the weighted distance measure provides better balance in practice because the balancing score can be poorly estimated. We emphasize the use of optimal matching based on efficient network algorithms. An illustration is based on the design of a case-control study of hepatitis B virus infection as a possible confounder and/or effect modifier of radiation-related primary liver cancer in atomic bomb survivors.

Adult↗

PubMed2006

Neonatal outcomes after prenatal exposure to selective serotonin reuptake inhibitor antidepressants and maternal depression using population-based linked health data.

CONTEXT: Prenatal exposure to selective serotonin reuptake inhibitor (SSRI) antidepressants and maternal depression both alter neonatal health, and distinguishing the effects of each influence remains challenging. OBJECTIVE: To determine whether exposure to SSRIs and depression differs from exposure to maternal depression alone. DESIGN: Using population health data, records of neonatal birth outcomes were linked to records of maternal health and prenatal maternal prescriptions for SSRIs. SETTING: Population of British Columbia, Canada. PARTICIPANTS: Mothers and their infants, representing all live births during a 39-month period (N = 119,547) (1998-2001). MAIN OUTCOME MEASURES: Outcomes from infants of depressed mothers treated with SSRIs (SE-D) were compared with outcomes from infants of depressed mothers not treated with medication (DE) and nonexposed controls. To control for maternal mental illness severity, propensity score matching was used to identify a comparison group of DE mothers who were similar to the SE-D mothers in characteristics in the year preceding and during pregnancy. RESULTS: Fourteen percent of mothers were diagnosed as having depression during their pregnancy, and the incidence of prenatal SSRI exposure increased from 2.3% to 5.0% during a 39-month period. Birth weight and gestational age for SE-D infants were significantly less than for DE infants, as was the proportion of infants born at less than 37 weeks (95% confidence interval [CI], -1 to -64, -0.25 to -0.45, and -0.009 to -0.04, respectively), although differences in the incidence of birth weight less than the 10th percentile for gestational age were not significant. An increased proportion of SE-D infants had neonatal respiratory distress (13.9% vs 7.8%), jaundice (9.4% vs 7.5%), and feeding problems (3.9% vs 2.4%) compared with DE infants (95% CI of difference, 0.042-0.079, 0.003-0.334, and 0.005-0.025, respectively). When outcomes were compared between SE-D and propensity score-matched DE neonates, SE-D was associated with increased incidence of birth weight below the 10th percentile and rates of respiratory distress. CONCLUSION: With linked population health data and propensity score matching, prenatal SE-D exposure was associated with an increased risk of low birth weight and respiratory distress, even when maternal illness severity was accounted for.

Birth Weight↗

PubMed2006

Gender disparities in percutaneous coronary interventions for acute myocardial infarction in Pennsylvania.

BACKGROUND: It has been shown that women are at greater risk than men of not receiving screening and treatment services for coronary heart disease. The purpose of this research was to determine whether there were gender disparities in the use of percutaneous coronary interventions (PCI) in the treatment of acute myocardial infarction (AMI) in Pennsylvania in 2000 and, if so, whether outcomes were affected. METHODS: Data included 10,170 patients treated with PCI and 21,181 patients medically managed in Pennsylvania hospitals. Multivariate analyses were performed using logistic regression to estimate the impact of gender on PCI. In addition, we performed retrospective matching on propensity scores to compare outcomes for women who were treated with PCI to comparable groups of women and men. RESULTS: After controlling for age, race/ethnicity, severity at admission, location of infarct, and source of admission, women had 24% lower odds than men of receiving PCI (P<0.0001). In a propensity score-matched sample of 3023 women who received PCI and 3023 women who did not, women who received PCI were significantly less likely to die (2.3% vs. 10.4%, P<0.0001). In a second propensity score-matched sample of 3329 women and 3329 similar men who received PCI, the difference in mortality was not statistically significant (1.59% vs. 1.92%, P=0.39). CONCLUSIONS: These results suggest that the morbidity and mortality associated with AMI in women could be reduced by increased use of PCI and that more women admitted for AMI should receive consideration for PCI.

Aged↗

PubMed2005

The epidemiology and attributable outcomes of candidemia in adults and children hospitalized in the United States: a propensity analysis.

BACKGROUND: Candida species are the fourth most common cause of bloodstream infection and are the leading cause of invasive fungal infection among hospitalized patients in the United States. However, the frequency and outcomes attributable to the infection are uncertain. This retrospective study set out to estimate the incidence of candidemia in hospitalized adults and children in the United States and to determine attributable mortality, length of hospital stay, and hospital charges related to candidemia. METHODS: We used the Nationwide Inpatient Sample 2000 for adult patients and the Kids' Inpatient Database 2000 for pediatric patients. We matched candidemia-exposed and candidemia-unexposed patients by the propensity scores for the probability of candidemia exposure, which were derived from patient characteristics. Attributable outcomes were calculated as the differences in estimates of outcomes between propensity score-matched patients with and without candidemia. RESULTS: In the United States in 2000, candidemia was diagnosed in an estimated 1118 hospital admissions of pediatric patients and 8949 hospital admissions of adult patients, yielding a frequency of 43 cases per 100,000 pediatric admissions (95% confidence interval [CI], 35-52 cases per 100,000 pediatric admissions) and 30 cases per 100,000 adult admissions (95% CI, 26-34 cases per 100,000 adult admissions). In pediatric patients, candidemia was associated with a 10.0% increase in mortality (95% CI, 6.2%-13.8%), a mean 21.1-day increase in length of stay (95% CI, 14.4-27.8 days), and a mean increase in total per-patient hospital charges of 92,266 dollars (95% CI, 65,058 dollars-119,474 dollars). In adult patients, candidemia was associated with a 14.5% increase in mortality (95% CI, 12.1%-16.9%), a mean 10.1-day increase in length of stay (95% CI, 8.9-11.3 days), and a mean increase in hospital charges of 39,331 dollars (95% CI, 33,604 dollars-45,602 dollars). CONCLUSION: The impact of candidemia on excess mortality, increased length of stay, and the burden of cost of hospitalization underscores the need for improved means of prevention and treatment of candidemia in adults and children.

Aged↗

PubMed2006

Effectiveness and cost-effectiveness of facilitated percutaneous coronary intervention compared with primary percutaneous coronary intervention in patients with ST-segment elevation myocardial infarction transferred from community hospitals.

BACKGROUND: Primary percutaneous coronary intervention ([PCI], percutaneous transluminal coronary angioplasty+stenting) for ST-segment elevation myocardial infarction (STEMI) is regarded as superior to fibrinolysis even if it means that patients need to be transferred from one center to another to undergo the procedure. However, this inevitable delay between symptom onset and PCI, caused by the time required to travel, might increase the occurrence of cardiac events. A hybrid method called facilitated PCI uses fibrinolysis and/or glycoprotein (GP) IIb/IIIa inhibitors before transfer to a tertiary medical center where urgent PCI might be performed. This approach, however, has not been systematically evaluated. OBJECTIVE: The purpose of this study was to compare the effectiveness (combined end point of in-hospital mortality, reinfarction, stroke, or emergency revascularization) and cost-effectiveness of utilizing a bolus thrombolytic agent with GP IIb/IIIa inhibitor followed by transfer to a tertiary institution for facilitated PCI or standard of care transfer without primary PCI drugs among patients presenting to a community hospital with STEMI. METHODS: This was a prospective, single-center, cohort study comprising data from STEMI patients transferred from community hospitals to Hartford Hospital, Hartford, Connecticut, from the years 2000 to 2003. At the time of analysis, patients receiving primary PCI were matched (1:1) with those receiving facilitated PCI, utilizing propensity scores to assure similar demographics. The combined incidence of major adverse cardiac end points (MACE) and total hospital costs was compared between groups. Non-parametric bootstrapping was conducted to calculate CIs for the incremental cost-effectiveness ratio and generate a quadrant analysis. RESULTS: Based on 254 propensity score-matched patients (127 facilitated PCI and 127 primary PCI), in-hospital MACE and total hospital costs were reduced by 61.3% and US 4563 dollars (2005), respectively, in patients receiving facilitated compared with primary PCI (P=0.021 and P=NS, respectively). Patients receiving facilitated PCI were more likely to have target lesion Thrombolysis in Myocardial Infarction (TIMI) III (normal) blood flow on cardiac catheterization than those receiving primary PCI (49.6% vs 30.7%; P=0.002). However, the rate of TIMI bleeding was similar in both groups (21.3% in the facilitated PCI group vs 18.9% in the primary PCI group). Nonsignificant reductions were observed in both intensive care unit (ICU) and total length of stay (LOS) (0.8 day and 1.0 day, respectively) compared with the primary PCI group. Bootstrap analysis revealed that of 25,000 samplings, facilitated PCI would likely be both more effective and less costly 94.6% of the time. CONCLUSIONS: The use of facilitated PCI in STEMI patients who initially presented to community hospitals and were transferred for PCI appeared to significantly reduce the incidence of MACE, and increase the likelihood of having baseline TIMI III blood flow at time of catheterization. Nonsignificant reductions were observed in total ICU and hospital LOS. However, there did not appear to be a significant effect on the incidence of bleeding in patients receiving facilitated PCI. Bootstrap analysis confirmed that facilitated PCI would be both a more effective and less costly strategy.

Adolescent↗

PubMed2005

The impact of aeromedical response to patients with moderate to severe traumatic brain injury.

STUDY OBJECTIVE: Aeromedical crews offer an advanced level of practice and rapid transport to definitive care; however, their efficacy remains unproven. Previous studies have used relatively small sample sizes or have been unable to adequately control for the effect of other potentially influential variables. Here we explore the impact of aeromedical response in patients with moderate to severe traumatic brain injury. METHODS: This was a retrospective analysis using our county trauma registry. All patients with head Abbreviated Injury Score of 3 or greater were included; interfacility transfers were excluded. The impact of aeromedical response was determined using logistic regression, adjusting for age, sex, mechanism, preadmission Glasgow Coma Scale score, head Abbreviated Injury Score, Injury Severity Score, and the presence of preadmission hypotension. Propensity scores were used to account for variability in selection of patients to undergo air versus ground transport. Patients with moderate and severe traumatic brain injury, as defined by head Abbreviated Injury Score and Glasgow Coma Scale score, were compared. Finally, aeromedical patients undergoing field intubation were compared with ground patients undergoing emergency department (ED) intubation. RESULTS: A total of 10,314 patients meeting all inclusion and exclusion criteria and with complete data sets were identified and included 3,017 transported by aeromedical crews. Overall mortality was 25% in the air- and ground-transported cohorts, but outcomes were significantly better for the aeromedical patients when adjusted for age, sex, mechanism of injury, hypotension, Glasgow Coma Scale score, head Abbreviated Injury Score, and Injury Severity Score (adjusted odds ratio [OR] 1.90; 95% confidence interval [CI] 1.60 to 2.25; P<.0001). Good outcomes (discharge to home, jail, psychiatric facility, rehabilitation, or leaving against medical advice) were also higher in aeromedical patients (adjusted OR 1.36; 95% CI 1.18 to 1.58; P<.0001). The primary benefit appeared to be in more severely injured patients, as reflected by head Abbreviated Injury Score and Glasgow Coma Scale score. Improved survival was also observed for air-transported patients intubated in the field versus ground-transported patients given emergency intubation in the ED (adjusted OR 1.42; 95% CI 1.13 to 1.78; P<.001). CONCLUSION: Here we analyze a large database of patients with moderate to severe traumatic brain injury. Aeromedical response appears to result in improved outcomes after adjustment for multiple influential factors in patients with moderate to severe traumatic brain injury. In addition, out-of-hospital intubation among air-transported patients resulted in better outcomes than ED intubation among ground-transported patients. Patients with more severe injuries appeared to derive the greatest benefit from aeromedical transport.

Abbreviated Injury Scale↗

PubMed2005

Results of multivariable logistic regression, propensity matching, propensity adjustment, and propensity-based weighting under conditions of nonuniform effect.

Observational studies often provide the only available information about treatment effects. Control of confounding, however, remains challenging. The authors compared five methods for evaluating the effect of tissue plasminogen activator on death among 6,269 ischemic stroke patients registered in a German stroke registry: multivariable logistic regression, propensity score-matched analysis, regression adjustment with the propensity score, and two propensity score-based weighted methods-one estimating the treatment effect in the entire study population (inverse-probability-of-treatment weights), another in the treated population (standardized-mortality-ratio weights). Between 2000 and 2001, 212 patients received tissue plasminogen activator. The crude odds ratio between tissue plasminogen activator and death was 3.35 (95% confidence interval: 2.28, 4.91). The adjusted odds ratio depended strongly on the adjustment method, ranging from 1.11 (95% confidence interval: 0.67, 1.84) for the standardized-mortality-ratio weighted to 10.77 (95% confidence interval: 2.47, 47.04) for the inverse-probability-of-treatment-weighted analysis. For treated patients with a low propensity score, risks of dying were high. Exclusion of patients with a propensity score of <5% yielded comparable odds ratios of approximately 1 for all methods. High levels of nonuniform treatment effect render summary estimates very sensitive to the weighting system explicit or implicit in an adjustment technique. Researchers need to be clear about the population for which an overall treatment estimate is most suitable.

Aged↗

PubMed2025

Partial Breast Irradiation for High Molecular Risk Early-Stage Breast Cancer.

PURPOSE: Partial breast irradiation (PBI) is a suitable and well-tolerated alternative to whole breast irradiation (WBI) following lumpectomy for many forms of low-risk, early-stage breast cancer. Molecular risk scores, such as the Oncotype DX recurrence score (ODX RS), are increasingly guiding systemic treatment decisions. However, molecular/genomic profiling for radiation therapy (RT) decision-making remains investigational, and it is unclear whether a high ODX RS should preclude the use of PBI. We compared oncologic outcomes among patients with high ODX RS (>25) treated with PBI versus WBI. METHODS AND MATERIALS: Patients who underwent breast conservation followed by PBI or WBI with ODX RS > 25 were ascertained from a prospectively maintained institutional database. Comparable PBI and WBI cohorts were generated in 1:5 fashion using propensity score matching based on salient clinicopathologic features. We evaluated the incidence of local recurrence (LR) as a function of RT approach. RESULTS: We identified 968 patients with an ODX RS > 25 who were treated with adjuvant RT, with a median age of 59 years (range, 25-86) and a median 5.3 years of follow-up. In a propensity matched cohort analysis that included 28 patients who received PBI matched to 140 who received WBI, we observed 3 LR events among those receiving PBI (2 of which were in different quadrants from the primary lesion) and 5 events among those receiving WBI. Among this cohort with ODX RS > 25, the 72-month cumulative incidence of LR following PBI was 7.9% (95% CI, 1.3%-23%) compared to 4.8% (95% CI, 1.6%-11%) following WBI (P = .6). CONCLUSIONS: In this cohort of patients with high ODX RS, few LRs were observed, and no statistically significant difference in LR was identified between PBI and WBI. Although these findings suggest that PBI may be considered in carefully-selected high-genomic-risk patients, larger studies with longer follow-up are needed to definitively establish the safety of this approach.

Humans↗

PubMed2006

Tumor necrosis factor alpha antagonist use and cancer in patients with rheumatoid arthritis.

OBJECTIVE: Concerns persist about a possible association between tumor necrosis factor alpha (TNFalpha) antagonist treatment and development of cancers in patients with rheumatoid arthritis (RA). This study was undertaken to estimate the association between treatment with biologic disease-modifying antirheumatic drugs (DMARDs) and development of cancer in patients with RA. METHODS: We conducted a cohort study pooling administrative databases from 2 US states and 1 Canadian province. A cohort of patients who had received a diagnosis of RA on > or =1 occasion and had been prescribed DMARDs was identified. We categorized patients with a prescription for a biologic DMARD as biologic DMARD users, and those with a prescription for methotrexate (MTX) but no biologic DMARD as MTX users. We used time-varying propensity scores to adjust for the large number of possible confounders and stratified proportional hazards regression to estimate the effects of biologic DMARDs on cancer. The primary end points were hematologic malignancies (lymphoma, multiple myeloma, and leukemia) and common solid tumors (colorectal, lung, stomach, breast, prostate, uterine, ovarian, urinary tract/bladder, and melanoma). RESULTS: The pooled cohort included 1,152 biologic DMARD users and 7,306 MTX users. We identified 11 hematologic malignancies and 46 solid tumors during 2,940 person-years of biologic DMARD use, and 88 hematologic malignancies and 558 solid tumors during 30,300 person-years of MTX use. Comparing biologic DMARD users with MTX users, the propensity score-adjusted pooled hazard ratio was 1.37 (95% confidence interval 0.71-2.65) for hematologic malignancies and 0.91 (95% confidence interval 0.65-1.26) for solid tumors. CONCLUSION: Our results indicate that users of biologic agents are unlikely to have a substantial increase in the risk of hematologic malignancies and solid tumors as compared with MTX users. Despite the use of large combined data sets, studying the effect of an infrequent exposure (biologic DMARDs) on rare diseases (hematologic malignancies) remains a challenge.

Aged↗

PubMed2004

Training residents in mitral valve surgery.

BACKGROUND: The safety of training residents in complex procedures has not been elucidated. In particular, the impact of resident-performed mitral valve surgery on patient outcomes is unknown. METHODS: All mitral valve procedures performed by residents between 1998 and 2003 were compared with those performed by staff surgeons. Operative mortality and a composite morbidity (reoperation for bleeding, myocardial infarction, infection, stroke, or ventilation > 24 hours) were compared using multivariate analysis. Individual outcomes were compared with the use of propensity scores. RESULTS: There were 1020 cardiac surgeries performed by residents, including 165 mitral valve procedures (86 replacements, 79 repairs). In the same period, the staff surgeons performed 261 mitral procedures. Crude operative mortality for isolated mitral procedures was 5.4% and 4.7% (resident and staff, respectively, p = 1.00). Mitral valve repair including combined procedures had an operative mortality of 3.8% and 4.3% (resident and staff, respectively, p = 1.00). The composite morbidity outcome was 29.7% and 35.3% for resident and staff-performed cases, respectively (p = 0.24). In multivariate analysis, resident was not associated with the adverse outcomes examined (OR 0.80, 95% CI, 0.47, 1.37). The incidence of major adverse outcomes for propensity score-matched mitral valve cases, including combined procedures, were similar between residents and staff, respectively: mortality, 7.4% versus 8.7% (p = 0.67), stroke, 4.0% versus 6.7% (p = 0.30), and reoperation for bleeding, 4.7% versus 9.4% (p = 0.11). CONCLUSIONS: There were no significant differences in morbidity and mortality in patients undergoing mitral valve surgery between resident and staff surgeons. It is possible to train residents to perform complex cardiac cases without adversely affecting outcomes.

Aged↗

PubMed2006

Retail tobacco outlet density and youth cigarette smoking: a propensity-modeling approach.

OBJECTIVES: We examined whether retail tobacco outlet density was related to youth cigarette smoking after control for a diverse range of neighborhood characteristics. METHODS: Data were gathered from 2116 respondents (aged 11 to 23 years) residing in 178 census tracts in Chicago, Ill. Propensity score stratification methods for continuous exposures were used to adjust for potentially confounding neighborhood characteristics, thus strengthening causal inferences. RESULTS: Retail tobacco outlets were disproportionately located in neighborhoods characterized by social and economic disadvantage. In a model that excluded neighborhood confounders, a marginally significant effect was found. Youths in areas at the highest 75th percentile in retail tobacco outlet density were 13% more likely (odds ratio [OR]=1.13; 95% confidence interval [CI]=0.99, 1.28) to have smoked in the past month compared with those living at the lowest 25th percentile. However, the relation became stronger and significant (OR=0.21; 95% CI=1.04, 1.41) after introduction of tract-level confounders and was statistically significant in the propensity score-adjusted model (OR = 1.20; 95% CI = 1.001, 1.44). Results did not differ significantly between minors and those legally permitted to smoke. CONCLUSIONS: Reductions in retail tobacco outlet density may reduce rates of youth smoking.

Adolescent↗

PubMed2006

Effect of antimalarials on thrombosis and survival in patients with systemic lupus erythematosus.

Antimalarials have shown beneficial effects on systemic lupus erythematosus (SLE) activity. Our aim was to investigate whether antimalarials protect against thrombosis and influence survival in SLE patients. A prospective cohort including 232 patients with SLE were included in the study at the time of lupus diagnosis. End points were documented thrombosis and death due to any cause. A Cox regression-multiple-failure time survival analysis model was fitted to establish the effect of antimalarials on the development of thrombosis. Kaplan-Meier survival curves and propensity score adjusted-Cox regression analysis were performed to investigate the effect of antimalarials use on survival. Of our subjects, 204 patients (88%) were women. 230 patients (99%) were white. 150 patients (64%) had ever received antimalarials. Median time on antimalarials was 52 months (range three to 228 months). The Cox multiple-failure time survival analysis showed that taking antimalarials was protective against thrombosis (HR 0.28, 95% CI 0.08-0.90), while aPL-positivity (HR 3.16, 95% CI 1.45-6.88) and previous thrombosis (HR 3.85, 95% CI 1.50-9.91) increased the risk of thrombotic events. Twenty-three patients died, 19 of whom (83%) had never received antimalarials. No patient treated with antimalarials died of cardiovascular complications. Cumulative 15-year survival rates were 0.68 for never versus 0.95 for ever treated patients (P < 0.001). Age at diagnosis and propensity score-adjusted HR for antimalarials ever versus never users was 0.14 (95% CI 0.04-0.48). Our study shows a protective effect of antimalarials against thrombosis and an increased survival of SLE patients taking these drugs. These data support the routine use of antimalarials in all patients with SLE.

Adult↗

PubMed2026

Non-tobacco nicotine dependence and postoperative complications after total ankle arthroplasty: A propensity-matched cohort study.

BACKGROUND: The clinical impact of non-tobacco nicotine dependence (NTND) is poorly defined. This study evaluated the association between NTND and complications following total ankle arthroplasty (TAA). METHODS: A retrospective cohort study using the TriNetX Research Network was performed. Adults undergoing primary TAA (Current Procedural Terminology [CPT] 27702) between 2010 and 2025 were included. Patients were categorized into NTND (International Classification of Diseases, Tenth Revision [ICD-10]: F17, excluding tobacco-specific codes) and nonsmoker cohorts. Propensity score matching (1:1) yielded 939 NTND patients and 939 controls. Ninety-day medical and wound complications and ≥ 2-year mechanical outcomes were assessed. RESULTS: NTND patients had higher rates of 90-day readmission (11.7% vs 6.5%; OR 1.9), wound disruption (4.3% vs 2.6%; OR 1.7), surgical site infection (3.1% vs 1.6%; OR 2.0), and sepsis (2.4% vs 1.1%; OR 2.3). At a minimum 2-year follow-up, NTND was not associated with increased risk of mechanical complications. CONCLUSION: These findings challenge the assumption that smokeless nicotine products are benign in the perioperative setting and support incorporating NTND screening and cessation counseling into preoperative optimization protocols. Future prospective studies are warranted to further characterize the dose-dependent effects of non-tobacco nicotine exposure and to evaluate the impact of perioperative cessation strategies on outcomes following TAA. LEVEL OF EVIDENCE: IV.

Humans↗