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PubMed2004

Effects of guideline-concordant antimicrobial therapy on mortality among patients with community-acquired pneumonia.

PURPOSE: National practice guidelines have recommended specific initial empiric antimicrobial regimens for patients with community-acquired pneumonia. Our aim was to determine the association between the use of guideline-concordant antimicrobial therapy and 30-day mortality in patients with pneumonia. METHODS: We conducted a retrospective cohort study at two tertiary teaching hospitals. Eligible patients were admitted with a diagnosis of community-acquired pneumonia, had a chest radiograph consistent with pneumonia, and had a discharge diagnosis of pneumonia. All eligible patients were identified and a random sample was abstracted. We determined whether the use of guideline-concordant antibiotics was associated with 30-day mortality in an analysis that adjusted for potential confounders using propensity scores. RESULTS: Information was obtained on 420 patients with pneumonia. The mean (+/- SD) age was 63 +/- 16 years, 355 were men, and 82 patients were initially admitted to the intensive care unit. At 30 days after presentation, 41 patients (9.8%) had died: 21 of 97 (21.7%) in the non-guideline-concordant group and 20 of 323 (6.2%) in the guideline-concordant group. Antibiotics were concordant with national guidelines in 323 patients. In the regression analysis, after adjustment for the propensity score, failure to comply with antimicrobial therapy guidelines was associated with increased 30-day mortality (odds ratio = 5.7; 95% confidence interval: 2.0 to 16.0). CONCLUSION: Receipt of antimicrobial regimens concordant with national published guidelines may reduce 30-day mortality among patients hospitalized with pneumonia.

Aged↗

PubMed2005

Impact of combined secondary prevention therapy after myocardial infarction: data from a nationwide French registry.

BACKGROUND: Several classes of medications improve survival in patients with coronary artery disease. Whether these medications, as used in the real world, have additive efficacy remains speculative. OBJECTIVES: To assess whether patients discharged on combined secondary prevention medications after acute myocardial infarction (AMI) have improved 1-year survival, compared with the action of any single class of medications. DESIGN AND SETTING: Nationwide registry of consecutive patients admitted to intensive care units for AMI in November 2000 in France. Multivariate Cox regression analysis, including a propensity score for the prescription of combined therapy, was used. RESULTS: Of the 2119 patients discharged alive, 1095 (52%) were prescribed a combination of antiplatelet agents, beta-blockers, and statins (triple therapy), of whom 567 (27%) also received angiotensin-converting enzyme inhibitors (quadruple therapy) and 528 (25%) did not. One-year survival was 97% in patients receiving triple combination therapy versus 88% in those who received either none, 1, or 2 of these medications (P < .0001). After multivariate adjustment including the propensity score, the hazard ratio for 1-year mortality in patients with triple combination therapy was 0.52 (95% CI 0.33-0.81). In patients with ejection fraction < or = 35%, beta-blockers and angiotensin-converting enzyme inhibitors were independent predictors of survival, and combination therapy had no additional prognostic value. CONCLUSIONS: Compared with the prescription of any single class of secondary prevention medications, combination therapy offers additional protection in patients with AMI.

Adrenergic beta-Agonists↗

PubMed2004

Left heart bypass during descending thoracic aortic aneurysm repair does not reduce the incidence of paraplegia.

BACKGROUND: The preferred technique for spinal cord protection during surgical repair of descending thoracic aortic aneurysms (DTAAs) remains controversial. The purpose of this retrospective analysis was to determine if the use of left heart bypass (LHB) reduced the incidence of paraplegia in patients who underwent DTAA repair. METHODS: Over a 15-year period 387 consecutive patients underwent surgical repair of DTAAs using either the "clamp-and-sew" technique (341 patients, 88.1%) or distal aortic perfusion via a LHB circuit (46 patients, 11.9%). Data regarding patient characteristics, operative variables, and outcomes were retrieved from a prospectively maintained database. The impact of LHB on the frequency of paraplegia was determined using univariate and propensity score analyses. RESULTS: There were 17 operative deaths (4.4%) including 11 patients (2.8%) who died within 30 days. Paraplegia occurred in 10 patients (2.6%). On univariate analysis increasing age (p = 0.03), increasing aortic clamp time (p < 0.001), increasing red blood cell transfusion requirements (p = 0.01), and acute dissection (p = 0.03) were associated with increased incidence of paraplegia. Patients who received LHB had a similar incidence of paraplegia (2/46, 4%) compared with those treated without LHB (8/341, 2.3%; p = 0.3). Both matching and stratification propensity score analyses confirmed that LHB was not associated with reduced risk of paraplegia. CONCLUSIONS: On retrospective analysis the use of LHB during DTAA repair did not reduce the incidence of spinal cord injury. The "clamp-and-sew" technique remains an appropriate approach to DTAA repair.

Aorta, Thoracic↗

PubMed2004

Effectiveness of platinum-based chemotherapy among elderly patients with advanced ovarian cancer.

BACKGROUND: Platinum-based chemotherapy is the standard of care for women with advanced ovarian cancer based on the results of randomized trials. We previously showed that only about half of women over the age of 65 years with this disease received platinum-based chemotherapy, and that the likelihood of receiving it decreases with age. METHODS: We used the Surveillance, Epidemiology, and End Results (SEER)-Medicare database to identify women diagnosed from 1/1/92 to 12/31/96 with stage III or IV ovarian cancer who survived > or =120 days beyond diagnosis, and were > or =65 years of age. Cox proportional hazards models and propensity scores were used to control for known predictors of receiving treatment and to estimate the relative effectiveness of different platinum-based regimens. RESULTS: Of the 1759 patients in the sample who met our eligibility criteria, 53% received platinum-based therapy. For this sample, the Cox proportional hazard ratio was 0.72 (95% CI, 0.62-0.91) for mortality associated with the use of any platinum-based therapy, and 0.59 (95% CI, 0.45-0.76) for combination platinum/paclitaxel therapy. Similar results were obtained using propensity score modeling. CONCLUSIONS: In this population-based study, we found that only about half of women with advanced ovarian cancer over age 65 were treated with platinum-based chemotherapy; however, survival improved by 38% in treated women, similar to the benefits described in randomized controlled trials among younger patients, and were greatest when platinum was combined with paclitaxel. An effort to increase the utilization of platinum combination therapy among older patients with advanced ovarian cancer is justified.

Aged↗

PubMed2001

Effects of angiotensin-converting enzyme inhibitors on the treatment of anemia with erythropoietin.

BACKGROUND: The hypothesis that angiotensin-converting enzyme (ACE) inhibitors interfere with the treatment of anemia with recombinant human erythropoietin (rHuEPO) remains controversial. To test this hypothesis, a retrospective analysis was conducted in a large group of hemodialysis patients with renal anemia. METHODS: The effects of ACE inhibitors in these patients were evaluated by measuring the weekly increment in hematocrit (DeltaHct) values within 12 weeks of the initiation of rHuEPO treatment. Results from 2213 rHuEPO naïve patients were compared between patients receiving rHuEPO alone and patients receiving both rHuEPO and ACE inhibitors. Because of the demographic differences between the two groups, a propensity score was used to eliminate the influence of confounding factors and to match the patient population in these two patient groups. Multiple regression analysis also was performed. RESULTS: When the DeltaHct values were compared directly between the two groups or were assessed by multiple regression analysis, no effect of ACE inhibitors was observed (P = 0.941 and P = 0.308, respectively). When the effects of ACE inhibitors on the treatment of anemia with rHuEPO were analyzed in 329 patients extracted from each group by their propensity score, DeltaHct did not differ between the two groups (P = 0.355). CONCLUSIONS: These results suggest that ACE inhibitors have no effect on the rHuEPO treatment for anemia in hemodialysis patients who were treated with a relatively low dose of ACE inhibitors and low-dose rHuEPO.

Adult↗

PubMed2004

Treatment outcomes in patients with migraine: an ex-post-facto comparison of two in-patient facilities.

BACKGROUND: In two hospitals we performed an open, prospective observational study on patients with chronic headache as a measure of internal quality assurance using identical methods. Available data were subordinately analysed in order to compare both studies. QUESTIONS: Are the patient samples of both hospitals comparable? If not, which form of statistical adjustment is recommended? Are there differences in the outcome measures of both facilities? METHODS: The outcomes were defined as differences between baseline values and values at discharge from hospital, respectively 6 months after. Frequency of headache attacks, intensity of pain, intensity of general complaints as well as of concomitant symptoms, and quality of life were determined in advance as dependent variables. To compare both patient groups univariate analysis of variance without and with inclusion of covariates were used. For calculating propensity scores (conditional probability of belonging to one of two groups) a logistic regression with the same covariates serving as independent variables was performed. PATIENTS: 426 patients with the main diagnosis "Migraine" and complete data sets concerning the covariates were selected for analysis. 87% of patients are female, the mean age is 45.5 +/- 11.7 years (range 14-73 yrs). RESULTS: 4 out of 11 potential covariates show statistically significant differences between the patients of both hospitals. Correct classification of patients by means of the propensity score succeeds in 67%. Comparing the outcomes at discharge from hospital, significant differences between both groups exist which are, with one exception, not affected by controlling for covariates. 6 months after discharge two of the initial differences between both patient groups are no longer present. These findings are independent from the statistical technique of risk adjustment. CONCLUSIONS: Because of the observed differences between both patient groups it is recommended to adjust data by regression analysis in order to enhance comparability. The choice for one of the two proposed techniques is secondary. With respect to the analyses clear differences between both hospitals exist in short-term outcomes, disappearing 6 months later.

Adolescent↗

PubMed2005

Statin use and risks of death or fatal rejection in the Heart Transplant Lipid Registry.

Although small, randomized trials have shown that statin use is associated with decreased risks of mortality and severe rejection, no study has examined statin therapy as used in actual practice in large numbers of heart transplant recipients. We analyzed data from the Heart Transplant Lipid Registry (n = 12 centers). Patients were included if they underwent transplantation between 1995 and 1999, survived >/=30 days after transplantation, and had >/=30 days of Registry follow-up. Multivariable Cox regression models, with propensity scoring performed to adjust for nonrandom allocation of statin therapy, were performed to determine the association of statin therapy with death and fatal rejection. The study included 1,186 patients, with a mean follow-up of 580 +/- 469 days; 937 patients (79%) received statin therapy. Overall, 71 patients (6%) died and 40 (3.4%) had fatal rejection. The statin group had a lower frequency of death (4% vs 13.7%, p <0.0001) and fatal rejection (2.4% vs 7.2%, p = 0.0001). Using multivariable Cox regression, with propensity scoring included to adjust for likelihood of receiving statin therapy, statin use was the only factor associated with lower risk of death (hazard ratio 0.29, 95% confidence interval 0.13 to 0.67) and fatal rejection (hazard ratio 0.27, 95% confidence interval 0.09 to 0.78). This study represents the largest population of heart transplant recipients analyzed for the relation between statin therapy and clinical outcomes in actual practice. Statin therapy was significantly associated with lower risk of death and fatal rejection, benefits that were independent of lipid values.

Chi-Square Distribution↗

PubMed2003

Effectiveness of lipid-lowering medications in outpatients with coronary heart disease in the Department of Veterans Affairs System.

Lipid therapy aimed at reducing low-density lipoprotein cholesterol has been shown, in several large-scale randomized controlled trials, to reduce coronary heart disease (CHD) morbidity and mortality and all-cause mortality in patients with established CHD. However, lipid therapy's effectiveness in usual clinical settings has not been extensively studied. The purpose of this study was to determine the effect of prescription lipid-lowering medication (LLM) on all-cause mortality in a cohort of patients with known CHD. We conducted a retrospective cohort study using linked administrative and clinical databases. Sixteen thousand four hundred seventy patients with CHD who were outpatients at 1 of 5 Veterans Affairs medical facilities in the upper midwest between 1994 and 1996 were identified and then followed until death or the end of the study (December 31, 2000). Pharmacy databases were used to determine whether patients had been prescribed LLMs. Demographics, co-morbid conditions, cardiac medications, and lipid levels were collected. Time-dependent Cox proportional hazards analyses, adjusted for confounding variables, and the propensity score for LLM use were performed to compare survival between those prescribed and those not prescribed LLM. During an average follow-up of 5.9 years, there were 4,821 recorded deaths in patients not prescribed LLM (51%) and 1,245 deaths in patients prescribed LLM (18%). On average, the treated cohort survived 15 months longer than the untreated group (p<0.0001). The age-adjusted hazards ratio associated with LLM use was 0.59 (95% confidence interval 0.55 to 0.63, p=0.0001). After adjusting for propensity score, age, and previous use of LLM, the hazard ratio associated with prescription of LLM was 0.77 (95% confidence interval 0.70 to 0.85, p<0.0001). This study confirms, in a standard clinical setting, the beneficial effects of LLM on total mortality in patients with established CHD. These data suggest that the benefits of lipid therapy observed in highly controlled randomized trials are attainable in usual clinical settings.

Aged↗

PubMed2006

Antegrade cerebral perfusion with a simplified technique: unilateral versus bilateral perfusion.

BACKGROUND: Selective antegrade cerebral perfusion has been introduced as a strategy of cerebral protection in operations on the aortic arch with hypothermic circulatory arrest. Several techniques of unilateral and bilateral cerebral perfusion have been described with varying results. METHODS: Patients underwent either unilateral cerebral perfusion with a cannula in the right subclavian artery or bilateral cerebral perfusion, with an additional cannula in the left carotid artery. A simplified Seldinger-type technique for subclavian artery cannulation was employed. Results were analyzed with multivariable logistic regression analysis and propensity score analysis to adjust for nonrandomized treatment assignment. RESULTS: Of 65 patients, 17 (26%) had unilateral cerebral perfusion. Mortality was 11% (n = 7); 14% (n = 9) had a stroke. In multivariable analysis, unilateral cerebral perfusion was significantly associated with stroke (odds ratio 6.6 [1.2 to 36]). Age more than 70 years was associated with in-hospital death (odds ratio 12 [1.3 to 113]), and concomitant coronary artery bypass graft surgery was associated with adverse outcome (odds ratio 23 [1.8 to 299]). Balancing variables in a propensity score analysis, stroke remained significantly more common with unilateral brain perfusion (29% versus 0%, p = 0.045). Complications associated with subclavian artery cannulation were encountered in 1 patient (1.5%). CONCLUSIONS: The described cannulation technique is safe and effective. Bilateral cerebral perfusion is easily achieved and is associated with decreased stroke risk, and should be the preferred brain protection strategy.

Aged↗

PubMed2004

OPCAB versus early mortality and morbidity: an issue between clinical relevance and statistical significance.

OBJECTIVE: To evaluate the impact of OPCAB on major postoperative events in a large consecutive cohort of patients, covering the complete spectrum of risk. METHODS: A consecutive series of 3333 CABG patients operated in a single institution (Jan/97-Jan/03) is analyzed after a complete (98%) midterm reengineering towards off-pump surgery (Oct/99). Patients in cardiogenic shock are excluded. The on- (N=1593) or off-pump (N=1740) datasets are comparable for most demographic and non-cardiac variability. The studied events are early mortality, early stroke, early infarct, early dialysis and hospital stay. Three methods adjust for possible patient selection: similar datasets, forced inclusion of a saturated OPCAB propensity score and finally multivariate correction. RESULTS: Non-risk adjusted. The 3-month survival was 96.7+/-0.4% (OPCAB) and 95.9+/-0.5% (ECC) (P=0.2). The 8-day freedom from stroke was 99.4+/-0.2% (OPCAB) and 98.5+/-0.3% (ECC) (P=0.004). The prevalence of dialysis was 1.67% in OPCAB and 2.27% in ECC (P=0.2). The 8-day freedom from infarct was 98.4+/-0.2% (OPCAB) and 98.3+/-0.2% (ECC) (P=0.7). The freedom from hospital discharge day 15 was 17.6+/-0.9% (OPCAB) and 18.4+/-0.8% (ECC) (P=0.001). Propensity score corrected and adjusted for event-related variability. The survival effect remained non-significant (P=0.3), also for patients with a EuroSCORE>8 (P=0.9). The stroke effect became non-significant (P=0.2), but stayed significant for patients with severe internal carotid artery stenosis (P=0.02). The dialysis-effect remained non-significant (P=0.6), also for patients with an elevated creatinine (P=0.7). The early infarct-effect remained non-significant (P=0.8), also for the female patients (P=0.8). The hospital discharge was significantly influenced by the OPCAB approach for the total group (P=0.02) as well as for the patients with EuroSCORE>8 (P=0.01). CONCLUSIONS: The observed 20% reduction of mortality, 60% reduction of stroke and 20% reduction of dialysis were partly neutralized by the adjusting methods and demand, at least, larger datasets to obtain statistical significance. Subdatasets with fewer patients but higher risk identified risk-reducing effects for stroke. Hospital stay was shortened by the OPCAB approach. The interactions between risk, number of patients and the risk-reducing effect are the cornerstones of evidence generation for the OPCAB approach. These results were obtained through a very strict reengineering and cannot be extended to all OPCAB programs.

Aged↗

PubMed2005

Beta-blockers improve in-hospital and long-term survival in patients with severe left ventricular dysfunction undergoing major vascular surgery.

OBJECTIVES: To study whether beta-blockers reduce in-hospital and long-term mortality in patients with severe left ventricular dysfunction (LVD) undergoing major vascular surgery. DESIGN: Observational cohort study. MATERIALS: Five hundred and eleven patients with severe LVD (ejection fraction<30%) undergoing major non-cardiac vascular surgery. METHODS: In all patients, cardiac risk factors, medication (including beta-blockers), and dobutamine stress echocardiography (DSE) results were noted prior to surgery. DSE was evaluated for rest and stress-induced new wall motion abnormalities. Endpoint was in-hospital and long-term mortality. Propensity scores for beta-blockers were calculated and regression models were used to analyse the relation between beta-blockers and mortality. RESULTS: Mean age was 64+/-11 years and 383 patients (75%) were male. 139 patients (27%) used beta-blockers. Stress-induced ischemia occurred in 82 patients (16%). Median follow-up was 7 years (interquartile range: 3-10). In-hospital and long-term mortality was observed in 64 (13%) and 171 (33%) patients, respectively. After adjusting for clinical variables, DSE results and propensity scores, beta-blockers were significantly associated with reduced in-hospital and long-term mortality (OR: 0.18, 95% CI: 0.04-0.74 and HR: 0.38, 95% CI: 0.22-0.65, respectively). CONCLUSION: In patients with severe LVD undergoing major vascular surgery, the use of beta-blockers is associated with a reduced incidence of in-hospital and long-term postoperative mortality.

Adrenergic beta-Antagonists↗

PubMed2006

Revascularization in patients with heart failure.

BACKGROUND: Although practice guidelines recommend coronary revascularization for patients with heart failure, the evidence to support this recommendation is weak. The objective of our study was to determine the association of coronary revascularization with survival in patients who have had heart failure. METHODS: Data were obtained from the Alberta Provincial Project for Outcomes Assessment in Coronary Heart Disease (APPROACH), a clinical outcome-monitoring initiative that has captured data on all patients undergoing cardiac catheterization in the province of Alberta since 1995. Our study included data from patients with a history of heart failure and with documented coronary artery disease; patients with normal coronary arteries or prior coronary artery bypass grafting (CABG) were excluded. We constructed survival curves and adjusted them by the corrected group prognosis method (incorporating all clinical variables in APPROACH). Propensity scores were used to account for clinical characteristics that could influence the decision to revascularize. RESULTS: A total of 2538 patients (mean age 68 yr, standard deviation [SD] 11 yr, 31% female) underwent revascularization; 1690 patients (mean age 69 [SD 11] yr, 34% female) did not. Crude 1-year mortality was 11.8% among patients who underwent revascularization, compared with 21.6% among those who did not. Adjusted survival curves diverged early and continued up to 7 years of follow-up (hazard ratio 0.50, 95% confidence interval 0.44-0.57). Propensity scores showed improved survival with revascularization across all quintiles of likelihood of revascularization. INTERPRETATION: This new evidence lends support to practice guidelines, which recommend revascularization in patients with heart failure and coronary disease.

Aged↗

PubMed2005

Statins are associated with better outcomes after carotid endarterectomy in symptomatic patients.

BACKGROUND AND PURPOSE: Statins have been associated with a reduction in mortality from noncardiac surgery. This study aimed to determine whether statin use on admission to hospital for carotid endarterectomy was associated with a reduction of in-hospital adverse outcomes. METHODS: Data describing patient characteristics, surgical indication, statin treatment, and in-hospital outcomes of death, ischemic stroke or death and cardiac outcomes were collected from a chart review of all patients (3360) undergoing carotid endarterectomy in Western Canada from January 2000 to December 2001. Outcomes of patients on statins versus those not on statins were compared using logistic regression to account for differences in patient characteristics, and propensity score methods to account for factors influencing patient allocation to statins. RESULTS: Eight hundred and fifteen of 2031 symptomatic patients and 665 of 1252 asymptomatic patients were on a statin at the time of hospital admission. Statin use by symptomatic patients was associated with reduced in-hospital mortality and in-hospital ischemic stroke or death, but not in-hospital cardiac outcomes (adjusted odds ratio 0.25 [CI, 0.07 to 0.90], 0.55 [CI, 0.32 to 0.95], 0.87 [CI, 0.49 to 1.54], respectively). The improvement in outcomes was robust when tested using propensity score matching. This association was not seen in asymptomatic patients on statins (adjusted odds ratio, in-hospital mortality 0.54 [CI, 0.13 to 2.24]; in-hospital ischemic stroke or death 1.34 [CI, 0.61 to 2.93]; in-hospital cardiac outcomes 1.37 [CI, 0.73 to 2.58]). CONCLUSIONS: These findings are suggestive of a protective effect of statin therapy in symptomatic patients pre-treated at the time of carotid endarterectomy, though this needs confirmation in a randomized controlled trial.

Aged↗

PubMed2005

Outcome in patients transferred for percutaneous coronary intervention (a national registry of myocardial infarction 2/3/4 analysis).

Hospital transfer is associated with delays in performance of primary percutaneous coronary intervention (PCI) for ST-elevation myocardial infarction. Given the limited number of interventional centers in the United States, the transfer of patients is widely practiced. We compared the outcome of patients who were transferred for primary PCI and determined whether prolonged door-to-balloon times were associated with increased mortality. Patients who presented within 12 hours with ST-segment elevation myocardial infarction and underwent transfer for primary PCI were identified from the National Registry of Myocardial Infarction database (NRMI databases 2, 3, and 4, n = 7,133). The short-term outcome of those who received early (< or =2 hours) was compared with that of those who received delayed primary PCI (>2 hours) using multivariate logistic regression analyses and propensity score methods. The door-to-balloon time for the early PCI group compared with the delayed PCI group was 99 +/- 16 versus 264 +/- 178 minutes, respectively (p <0.0001). The early PCI group had less recurrent ischemia and angina (5.8% vs 10.1%, p <0.001), less cardiogenic shock (5.1% vs 8.9%, p <0.001), and shorter length of hospital stay (4.4 +/- 3.5 vs 5.4 +/- 4.7 days, p <0.001). In-hospital mortality was lower for the early PCI group than for the delayed PCI group (2.7% vs 6.2%, p < 0.001; entire cohort 5.7%). Comparison of patients matched on propensity score (n = 993) showed that mortality was lower in the early than in the delayed PCI group (2.6% vs 4.6%, p = 0.014, c-statistic 0.67). In conclusion, <4% of patients who received PCI were treated within the recommended guideline of < 120 minutes by the American College of Cardiology/American Heart Association. Door-to-balloon times <2 hours in patients who undergo transfer for PCI is associated with a significant decrease in short-term mortality, which suggests that efforts must be made to decrease transfer delays.

Angioplasty, Balloon, Coronary↗

PubMed2003

Association between antenatal cytokine production and the development of atopy and asthma at age 6 years.

BACKGROUND: Various lines of evidence suggest that antenatal factors are important in determining susceptibility to atopy and asthma. One possible mechanism is cytokines, production of which in the placenta is high throughout gestation and which protect placental integrity via control of local immunological homoeostasis. We investigated antenatal cytokine concentrations in a prospective birth cohort, intensively monitored for atopy and asthma outcomes at age 6 years. METHODS: Cryopreserved cord-blood serum samples from 407 children were assayed for interleukins 4, 5, 6, 10, 12, and 13, interferon gamma, and tumour necrosis factor alpha (TNFalpha). Associations between family, antenatal, and perinatal factors, cord-blood cytokine concentrations, and atopy or asthma outcomes were analysed by logistic regression. Causal effects of cytokines on outcomes were estimated by propensity scores based on family, antenatal, and perinatal factors. FINDINGS: Detectable cord-blood concentrations of interleukin 4 and interferon gamma were each associated with lower risk of physician-diagnosed asthma (adjusted odds ratios 0.60 [95% CI 0.37-0.99] and 0.60 [0.37-0.97] respectively), current asthma (0.59 [0.33-1.00] and 0.39 [0.22-0.71]), and current wheeze (0.55 [0.32-0.93] and 0.52 [0.31-0.90]) and atopy (sensitisation to some inhalant allergens) outcomes at 6 years. High concentrations of TNFalpha were associated with lower risk of atopy but not with asthma risk. These associations were broadly unaltered by propensity-score adjustment. Maternal smoking was associated with higher risk of both wheeze at 6 years and lower concentrations of interleukin 4 and interferon gamma in cord blood. INTERPRETATION: The mechanism underlying attenuated T-helper-1/T-helper-2 cytokine production in high-risk children also apparently operates in control of cytokine production in the fetoplacental unit. The finding that this mechanism is dysregulated by maternal smoking suggests it is a target for antenatal environmental factors relevant to asthma aetiology.

Asthma↗

PubMed2005

Maternal employment and child development: a fresh look using newer methods.

The employment rate for mothers with young children has increased dramatically over the past 25 years. Estimating the effects of maternal employment on children's development is challenged by selection bias and the missing data endemic to most policy research. To address these issues, this study uses propensity score matching and multiple imputation. The authors compare outcomes across 4 maternal employment patterns: no work in first 3 years postbirth, work only after 1st year, part-time work in 1st year, and full-time work in 1st year. Our results demonstrate small but significant negative effects of maternal employment on children's cognitive outcomes for full-time employment in the 1st year postbirth as compared with employment postponed until after the 1st year. Multiple imputation yields noticeably different estimates as compared with a complete case approach for many measures. Differences between results from propensity score approaches and regression modeling are often minimal.

Child↗

PubMed2002

Elimination of cardiopulmonary bypass improves early survival for multivessel coronary artery bypass patients.

BACKGROUND: Coronary artery bypass graft (CABG) surgery performed without cardiopulmonary bypass (CPB) is currently increasing in clinical practice. Decreased morbidity associated with off-pump (OP) CABG in selected risk groups examined in relatively small, single institution groups has been the focus of most recent studies. The purpose of this study was to determine the independent impact of CPB on early survival in all isolated multivessel CABG patients undergoing surgery in two large institutions with established experience in OPCABG techniques. METHODS: A review of two large databases employed by multiple surgeons in the hospitals of two institutions identified 8,758 multivessel CABG procedures performed from January 1998 through July 2000. In all, 8,449 procedures were included in a multivariate logistic regression analysis to determine the relative impact of CPB on mortality independent of known risk factors for mortality. Procedures were also divided into two treatment groups based on the use of CPB: 6,466 had CABG with CPB (CABG-CPB), 1,983 had CABG without CPB (OPCABG). Disparities between groups were identified by univariate analysis of 17 preoperative risk factors and treatment groups were compared by Parsonnet's risk stratification model. Finally, computer-matched groups based on propensity score for institution selection for OPCABG were combined and analyzed by a logistic regression model predicting risk for mortality. RESULTS: CABG-CPB was associated with increased mortality compared with OPCABG by univariate analysis, 3.5% versus 1.8%, despite a lower predicted risk in the CABG-CPB group. CPB was associated with increased mortality by multiple logistic regression analysis with an odds ratio of 1.79 (95% confidence interval = 1.24 to 2.67). An increased risk of mortality associated with CPB was also determined by logistic regression analysis of the combined computer-matched groups based on OPCABG-selection propensity scores with an odds ratio of 1.9 (95% confidence interval = 1.2 to 3.1). CONCLUSIONS: Elimination of CPB improves early survival in multivessel CABG patients. Rigorous attempts to statistically account for selection bias maintained a clear association between CPB and increased mortality. Larger multiinstitutional studies are needed to confirm these findings and determine the most appropriate application of OPCABG.

Aged↗

PubMed2000

Health outcomes after prostatectomy or radiotherapy for prostate cancer: results from the Prostate Cancer Outcomes Study.

BACKGROUND: Radical prostatectomy and external beam radiotherapy are the two major therapeutic options for treating clinically localized prostate cancer. Because survival is often favorable regardless of therapy, treatment decisions may depend on other therapy-specific health outcomes. In this study, we compared the effects of two treatments on urinary, bowel, and sexual functions and on general health-related quality-of-life outcomes over a 2-year period following initial treatment. METHODS: A diverse cohort of patients aged 55-74 years who were newly diagnosed with clinically localized prostate cancer and received either radical prostatectomy (n = 1156) or external beam radiotherapy (n = 435) were included in this study. A propensity score was used to balance the two treatment groups because they differed in some baseline characteristics. This score was used in multivariable cross-sectional and longitudinal regression analyses comparing the treatment groups. All statistical tests were two-sided. RESULTS: Almost 2 years after treatment, men receiving radical prostatectomy were more likely than men receiving radiotherapy to be incontinent (9.6% versus 3.5%; P:<.001) and to have higher rates of impotence (79.6% versus 61.5%; P:<.001), although large, statistically significant declines in sexual function were observed in both treatment groups. In contrast, men receiving radiotherapy reported greater declines in bowel function than did men receiving radical prostatectomy. All of these differences remained after adjustments for propensity score. The treatment groups were similar in terms of general health-related quality of life. CONCLUSIONS: There are important differences in urinary, bowel, and sexual functions over 2 years after different treatments for clinically localized prostate cancer. In contrast to previous reports, these outcome differences reflect treatment delivered to a heterogeneous group of patients in diverse health care settings. These results provide comprehensive and representative information about long-term treatment complications to help guide and inform patients and clinicians about prostate cancer treatment decisions.

Aged↗