98 resultados para Propensity


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Medial arterial calcification is accelerated in patients with CKD and strongly associated with increased arterial rigidity and cardiovascular mortality. Recently, a novel in vitro blood test that provides an overall measure of calcification propensity by monitoring the maturation time (T50) of calciprotein particles in serum was described. We used this test to measure serum T50 in a prospective cohort of 184 patients with stages 3 and 4 CKD, with a median of 5.3 years of follow-up. At baseline, the major determinants of serum calcification propensity included higher serum phosphate, ionized calcium, increased bone osteoclastic activity, and lower free fetuin-A, plasma pyrophosphate, and albumin concentrations, which accounted for 49% of the variation in this parameter. Increased serum calcification propensity at baseline independently associated with aortic pulse wave velocity in the complete cohort and progressive aortic stiffening over 30 months in a subgroup of 93 patients. After adjustment for demographic, renal, cardiovascular, and biochemical covariates, including serum phosphate, risk of death among patients in the lowest T50 tertile was more than two times the risk among patients in the highest T50 tertile (adjusted hazard ratio, 2.2; 95% confidence interval, 1.1 to 5.4; P=0.04). This effect was lost, however, after additional adjustment for aortic stiffness, suggesting a shared causal pathway. Longitudinally, serum calcification propensity measurements remained temporally stable (intraclass correlation=0.81). These results suggest that serum T50 may be helpful as a biomarker in designing methods to improve defenses against vascular calcification.

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We examined outcomes and trends in surgery and radiation use for patients with locally advanced esophageal cancer, for whom optimal treatment isn't clear. Trends in surgery and radiation for patients with T1-T3N1M0 squamous cell or adenocarcinoma of the mid or distal esophagus in the Surveillance, Epidemiology, and End Results database from 1998 to 2008 were analyzed using generalized linear models including year as predictor; Surveillance, Epidemiology, and End Results doesn't record chemotherapy data. Local treatment was unimodal if patients had only surgery or radiation and bimodal if they had both. Five-year cancer-specific survival (CSS) and overall survival (OS) were analyzed using propensity-score adjusted Cox proportional-hazard models. Overall 5-year survival for the 3295 patients identified (mean age 65.1 years, standard deviation 11.0) was 18.9% (95% confidence interval: 17.3-20.7). Local treatment was bimodal for 1274 (38.7%) and unimodal for 2021 (61.3%) patients; 1325 (40.2%) had radiation alone and 696 (21.1%) underwent only surgery. The use of bimodal therapy (32.8-42.5%, P = 0.01) and radiation alone (29.3-44.5%, P < 0.001) increased significantly from 1998 to 2008. Bimodal therapy predicted improved CSS (hazard ratios [HR]: 0.68, P < 0.001) and OS (HR: 0.58, P < 0.001) compared with unimodal therapy. For the first 7 months (before survival curve crossing), CSS after radiation therapy alone was similar to surgery alone (HR: 0.86, P = 0.12) while OS was worse for surgery only (HR: 0.70, P = 0.001). However, worse CSS (HR: 1.43, P < 0.001) and OS (HR: 1.46, P < 0.001) after that initial timeframe were found for radiation therapy only. The use of radiation to treat locally advanced mid and distal esophageal cancers increased from 1998 to 2008. Survival was best when both surgery and radiation were used.

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Investigating the new product portfolio innovativeness of family firms connects two important topics that have recently received considerable attention in innovation and family firm research. First, new product portfolio innovativeness has been identified as a critical determinant of firm performance. Second, research on family firms has focused on the questions of if and why family firms are more or less innovative than other organizational forms. Research investigating the innovativeness of family firms has often applied a risk-oriented perspective by identifying socioemotional wealth (SEW) as the main reference that determines firm behavior. Thus, prior research has mainly focused on the organizational context to predict innovation-related family firm behavior and neglected the impact of preferences and the behavior of the chief executive officer (CEO), which have both been shown to affect firm outcomes. Hence, this study aims to extend the previous research by introducing the CEO's disposition to organizational context variables to explain the new product portfolio innovativeness of small and medium-sized family firms. Specifically, this study explores how the organizational context (i.e., ownership by top management team [TMT] family members and generation in charge of the family firm) of family firms interacts with CEO risk-taking propensity to affect new product portfolio innovativeness. Using a sample of 114 German CEOs of small and medium-sized family firms operating in manufacturing industries, the results show that CEO risk-taking propensity has a positive effect on new product portfolio innovativeness. Moreover, the analyses show that the organizational context of family firms impacts the relationship between CEO risk-taking propensity and new product portfolio innovativeness. Specifically, the relationship between CEO risk-taking propensity and new product portfolio innovativeness is weaker if levels of ownership by TMT family members are high (high SEW). Additionally, the effect of CEO risk-taking propensity on new product portfolio innovativeness is stronger in family firms at earlier generational stages (high SEW). This result suggests that if SEW is a strong reference, family firm-specific characteristics can affect individual dispositions and, in turn, the behaviors of executives. Therefore, this study helps extend the knowledge on the determinants of new product portfolio innovativeness of family firms by considering an individual CEO preference and the organizational context variables of family firms simultaneously.

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Aims: To compare clinical outcome of Amplatzer PFO (APFO) to Cardia PFO (CPFO) occluder. Percutaneous patent foramen ovale (PFO) closure prevents stroke recurrence in stroke due to paradoxical embolism. Methods and results: The primary endpoint was a composite of stroke, TIA, or peripheral embolism at follow-up. The secondary endpoint was residual shunt. Outcome was compared among 934 (APFO: 712; CPFO: 222) patients, and in 297 propensity score-matched patients. The primary endpoint occurred in 29 patients (0.71/100 patient-years): four (2%) with the CPFO (0.31/100 patient-years), and 25 (4%) with the APFO (0.89/100 patient-years) (p=0.20). Residual shunt at six months was more frequent with the CPFO (31% versus 9%, p<0.001). No differences in residual shunts were seen at the last available echocardiographic follow-up (9±18 months): APFO 11%, CPFO 14%, p=0.22. Conclusions: This study suggests that PFO closure with APFO or CPFO is equally effective for the prevention of recurrent events. Residual shunt was more frequent at six months with CPFO, but was similar to APFO at later follow-up.

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Propensity score (PS) techniques are useful if the number of potential confounding pretreatment variables is large and the number of analysed outcome events is rather small so that conventional multivariable adjustment is hardly feasible. Only pretreatment characteristics should be chosen to derive PS, and only when they are probably associated with outcome. A careful visual inspection of PS will help to identify areas of no or minimal overlap, which suggests residual confounding, and trimming of the data according to the distribution of PS will help to minimise residual confounding. Standardised differences in pretreatment characteristics provide a useful check of the success of the PS technique employed. As with conventional multivariable adjustment, PS techniques cannot account for confounding variables that are not or are only imperfectly measured, and no PS technique is a substitute for an adequately designed randomised trial.

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BACKGROUND In patients with cardiogenic shock, data on the comparative safety and efficacy of drug-eluting stents (DESs) vs. bare metal stents (BMSs) are lacking. We sought to assess the performance of DESs compared with BMSs among patients with cardiogenic shock undergoing percutaneous coronary intervention (PCI). METHODS Out of 236 patients with acute coronary syndromes complicated by cardiogenic shock, 203 were included in the final analysis. The primary endpoint included death, and the secondary endpoint of major adverse cardiac and cerebrovascular events (MACCEs) included the composite of death, myocardial infarction, any repeat revascularization and stroke. Patients were followed for a minimum of 30 days and up to 4 years. As stent assignment was not random, we performed a propensity score analysis to minimize potential bias. RESULTS Among patients treated with DESs, there was a lower risk of the primary and secondary endpoints compared with BMSs at 30 days (29 vs. 56%, P < 0.001; 34 vs. 58%, P = 0.001, respectively) and during long-term follow-up [hazard ratio 0.43, 95% confidence interval (CI) 0.29-0.65, P < 0.001; hazard ratio 0.49, 95% CI 0.34-0.71, P < 0.001, respectively]. After propensity score adjustment, all-cause mortality was reduced among patients treated with DESs compared with BMSs both at 30 days [adjusted odds ratio (OR) 0.26, 95% CI 0.11-0.62; P = 0.002] and during long-term follow-up (adjusted hazard ratio 0.40, 95% CI 0.22-0.72; P = 0.002). The rate of MACCE was lower among patients treated with DESs compared with those treated with BMSs at 30 days (adjusted OR 0.42, 95% CI 0.19-0.95; P = 0.036). The difference in MACCEs between devices approached significance during long-term follow-up (adjusted hazard ratio 0.60, 95% CI 0.34-1.01; P = 0.052). CONCLUSION DESs appear to be associated with improved clinical outcomes, including a reduction in all-cause mortality compared with BMSs among patients undergoing PCI for cardiogenic shock, possibly because of a pacification of the infarct-related artery by anti-inflammatory drug. The results of this observational study require confirmation in an appropriately powered randomized trial.

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BACKGROUND During 2007 and 2008 it is likely that millions of patients in the US received heparin contaminated (CH) with oversulfated chondroitin sulfate, which was associated with anaphylactoid reactions. We tested the hypothesis that CH was associated with serious morbidity, mortality, intensive care unit (ICU) stay and heparin-induced thrombocytopenia following adult cardiac surgery. METHODS AND FINDINGS We conducted a single center, retrospective, propensity-matched cohort study during the period of CH and the equivalent time frame in the three preceding or the two following years. Perioperative data were obtained from the institutional record of the Society of Thoracic Surgeons National Database, for which the data collection is prospective, standardized and performed by independent investigators. After matching, logistic regression was performed to evaluate the independent effect of CH on the composite adverse outcome (myocardial infarction, stroke, pneumonia, dialysis, cardiac arrest) and on mortality. Cox regression was used to determine the association between CH and ICU length of stay. The 1∶5 matched groups included 220 patients potentially exposed to CH and 918 controls. There were more adverse outcomes in the exposed cohort (20.9% versus 12.0%; difference  =  8.9%; 95% CI 3.6% to 15.1%, P < 0.001) with an odds ratio for CH of 2.0 (95% CI, 1.4 to 3.0, P < 0.001). In the exposed group there was a non-significant increase in mortality (5.9% versus 3.5%, difference = 2.4%; 95% CI, -0.4 to 3.5%, P  =  0.1), the median ICU stay was longer by 14.1 hours (interquartile range -26.6 to 79.8, S = 3299, P = 0.0004) with an estimated hazard ratio for CH of 1.2 (95% CI, 1.0 to 1.4, P = 0.04). There was no difference in nadir platelet counts between cohorts. CONCLUSIONS The results from this single center study suggest the possibility that contaminated heparin might have contributed to serious morbidity following cardiac surgery.

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BACKGROUND Many orthopaedic surgical procedures can be performed with either regional or general anesthesia. We hypothesized that total hip arthroplasty with regional anesthesia is associated with less postoperative morbidity and mortality than total hip arthroplasty with general anesthesia. METHODS This retrospective propensity-matched cohort study utilizing the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) database included patients who had undergone total hip arthroplasty from 2007 through 2011. After matching, logistic regression was used to determine the association between the type of anesthesia and deep surgical site infections, hospital length of stay, thirty-day mortality, and cardiovascular and pulmonary complications. RESULTS Of 12,929 surgical procedures, 5103 (39.5%) were performed with regional anesthesia. The adjusted odds for deep surgical site infections were significantly lower in the regional anesthesia group than in the general anesthesia group (odds ratio [OR] = 0.38; 95% confidence interval [CI] = 0.20 to 0.72; p < 0.01). The hospital length of stay (geometric mean) was decreased by 5% (95% CI = 3% to 7%; p < 0.001) with regional anesthesia, which translates to 0.17 day for each total hip arthroplasty. Regional anesthesia was also associated with a 27% decrease in the odds of prolonged hospitalization (OR = 0.73; 95% CI = 0.68 to 0.89; p < 0.001). The mortality rate was not significantly lower with regional anesthesia (OR = 0.78; 95% CI = 0.43 to 1.42; p > 0.05). The adjusted odds for cardiovascular complications (OR = 0.61; 95% CI = 0.44 to 0.85) and respiratory complications (OR = 0.51; 95% CI = 0.33 to 0.81) were all lower in the regional anesthesia group. CONCLUSIONS Compared with general anesthesia, regional anesthesia for total hip arthroplasty was associated with a reduction in deep surgical site infection rates, hospital length of stay, and rates of postoperative cardiovascular and pulmonary complications. These findings could have an important medical and economic impact on health-care practice.

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One key hypothesis in the study of brain size evolution is the expensive tissue hypothesis; the idea that increased investment into the brain should be compensated by decreased investment into other costly organs, for instance the gut. Although the hypothesis is supported by both comparative and experimental evidence, little is known about the potential changes in energetic requirements or digestive traits following such evolutionary shifts in brain and gut size. Organisms may meet the greater metabolic requirements of larger brains despite smaller guts via increased food intake or better digestion. But increased investment in the brain may also hamper somatic growth. To test these hypotheses we here used guppy (Poecilia reticulata) brain size selection lines with a pronounced negative association between brain and gut size and investigated feeding propensity, digestive efficiency (DE), and juvenile growth rate. We did not find any difference in feeding propensity or DE between large- and small-brained individuals. Instead, we found that large-brained females had slower growth during the first 10 weeks after birth. Our study provides experimental support that investment into larger brains at the expense of gut tissue carries costs that are not necessarily compensated by a more efficient digestive system.

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OBJECTIVE The purpose of this study was to investigate outcomes of patients treated with prasugrel or clopidogrel after percutaneous coronary intervention (PCI) in a nationwide acute coronary syndrome (ACS) registry. BACKGROUND Prasugrel was found to be superior to clopidogrel in a randomized trial of ACS patients undergoing PCI. However, little is known about its efficacy in everyday practice. METHODS All ACS patients enrolled in the Acute Myocardial Infarction in Switzerland (AMIS)-Plus registry undergoing PCI and being treated with a thienopyridine P2Y12 inhibitor between January 2010-December 2013 were included in this analysis. Patients were stratified according to treatment with prasugrel or clopidogrel and outcomes were compared using propensity score matching. The primary endpoint was a composite of death, recurrent infarction and stroke at hospital discharge. RESULTS Out of 7621 patients, 2891 received prasugrel (38%) and 4730 received clopidogrel (62%). Independent predictors of in-hospital mortality were age, Killip class >2, STEMI, Charlson comorbidity index >1, and resuscitation prior to admission. After propensity score matching (2301 patients per group), the primary endpoint was significantly lower in prasugrel-treated patients (3.0% vs 4.3%; p=0.022) while bleeding events were more frequent (4.1% vs 3.0%; p=0.048). In-hospital mortality was significantly reduced (1.8% vs 3.1%; p=0.004), but no significant differences were observed in rates of recurrent infarction (0.8% vs 0.7%; p=1.00) or stroke (0.5% vs 0.6%; p=0.85). In a predefined subset of matched patients with one-year follow-up (n=1226), mortality between discharge and one year was not significantly reduced in prasugrel-treated patients (1.3% vs 1.9%, p=0.38). CONCLUSIONS In everyday practice in Switzerland, prasugrel is predominantly used in younger patients with STEMI undergoing primary PCI. A propensity score-matched analysis suggests a mortality benefit from prasugrel compared with clopidogrel in these patients.

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OBJECTIVE To assess whether palliative primary tumor resection in colorectal cancer patients with incurable stage IV disease is associated with improved survival. BACKGROUND There is a heated debate regarding whether or not an asymptomatic primary tumor should be removed in patients with incurable stage IV colorectal disease. METHODS Stage IV colorectal cancer patients were identified in the Surveillance, Epidemiology, and End Results database between 1998 and 2009. Patients undergoing surgery to metastatic sites were excluded. Overall survival and cancer-specific survival were compared between patients with and without palliative primary tumor resection using risk-adjusted Cox proportional hazard regression models and stratified propensity score methods. RESULTS Overall, 37,793 stage IV colorectal cancer patients were identified. Of those, 23,004 (60.9%) underwent palliative primary tumor resection. The rate of patients undergoing palliative primary cancer resection decreased from 68.4% in 1998 to 50.7% in 2009 (P < 0.001). In Cox regression analysis after propensity score matching primary cancer resection was associated with a significantly improved overall survival [hazard ratio (HR) of death = 0.40, 95% confidence interval (CI) = 0.39-0.42, P < 0.001] and cancer-specific survival (HR of death = 0.39, 95% CI = 0.38-0.40, P < 0.001). The benefit of palliative primary cancer resection persisted during the time period 1998 to 2009 with HRs equal to or less than 0.47 for both overall and cancer-specific survival. CONCLUSIONS On the basis of this population-based cohort of stage IV colorectal cancer patients, palliative primary tumor resection was associated with improved overall and cancer-specific survival. Therefore, the dogma that an asymptomatic primary tumor never should be resected in patients with unresectable colorectal cancer metastases must be questioned.

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Background: The efficacy of cognitive behavioral therapy (CBT) for the treatment of depressive disorders has been demonstrated in many randomized controlled trials (RCTs). This study investigated whether for CBT similar effects can be expected under routine care conditions when the patients are comparable to those examined in RCTs. Method: N=574 CBT patients from an outpatient clinic were stepwise matched to the patients undergoing CBT in the National Institute of Mental Health Treatment of Depression Collaborative Research Program (TDCRP). First, the exclusion criteria of the RCT were applied to the naturalistic sample of the outpatient clinic. Second, propensity score matching (PSM) was used to adjust the remaining naturalistic sample on the basis of baseline covariate distributions. Matched samples were then compared regarding treatment effects using effect sizes, average treatment effect on the treated (ATT) and recovery rates. Results: CBT in the adjusted naturalistic subsample was as effective as in the RCT. However, treatments lasted significantly longer under routine care conditions. Limitations: The samples included only a limited amount of common predictor variables and stemmed from different countries. There might be additional covariates, which could potentially further improve the matching between the samples. Conclusions: CBT for depression in clinical practice might be equally effective as manual-based treatments in RCTs when they are applied to comparable patients. The fact that similar effects under routine conditions were reached with more sessions, however, points to the potential to optimize treatments in clinical practice with respect to their efficiency.

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PURPOSE To compare patient outcomes and complication rates after different decompression techniques or instrumented fusion (IF) in lumbar spinal stenosis (LSS). METHODS The multicentre study was based on Spine Tango data. Inclusion criteria were LSS with a posterior decompression and pre- and postoperative COMI assessment between 3 and 24 months. 1,176 cases were assigned to four groups: (1) laminotomy (n = 642), (2) hemilaminectomy (n = 196), (3) laminectomy (n = 230) and (4) laminectomy combined with an IF (n = 108). Clinical outcomes were achievement of minimum relevant change in COMI back and leg pain and COMI score (2.2 points), surgical and general complications, measures taken due to complications, and reintervention on the index level based on patient information. The inverse propensity score weighting method was used for adjustment. RESULTS Laminotomy, hemilaminectomy and laminectomy were significantly less beneficial than laminectomy in combination with IF regarding leg pain (ORs with 95% CI 0.52, 0.34-0.81; 0.25, 0.15-0.41; 0.44, 0.27-0.72, respectively) and COMI score improvement (ORs with 95% CI 0.51, 0.33-0.81; 0.30, 0.18-0.51; 0.48, 0.29-0.79, respectively). However, the sole decompressions caused significantly fewer surgical (ORs with 95% CI 0.42, 0.26-0.69; 0.33, 0.17-0.63; 0.39, 0.21-0.71, respectively) and general complications (ORs with 95% CI 0.11, 0.04-0.29; 0.03, 0.003-0.41; 0.25, 0.09-0.71, respectively) than laminectomy in combination with IF. Accordingly, the likelihood of required measures was also significantly lower after laminotomy (OR 0.28, 95% CI 0.17-0.46), hemilaminectomy (OR 0.28, 95% CI 0.15-0.53) and after laminectomy (OR 0.39, 95% CI 0.22-0.68) in comparison with laminectomy with IF. The likelihood of a reintervention was not significantly different between the treatment groups. DISCUSSION As already demonstrated in the literature, decompression in patients with LSS is a very effective treatment. Despite better patient outcomes after laminectomy in combination with IF, caution is advised due to higher rates of surgical and general complications and consequent required measures. Based on the current study, laminotomy or laminectomy, rather than hemilaminectomy, is recommendable for minimum relevant pain relief.

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Research on the foundations of social trust mainly concentrates on the evaluation of one's social environment. Empirical evidence focusing on the psychological origins of social trust is quite rare and the findings of these few studies remain inconclusive. Two innovations are proposed in order to systemize the knowledge about the foundations of social trust. First, we propose using a trust measure that is sensitive to different categories of trustees and refers to a realistic situation. Second, we argue for a broad conception of personality, rather than focusing only on selected attributes. Using data from a unique Swiss population survey, we show that the impact of personality traits on trust in strangers is stronger than on trust in friends. While conscientiousness and openness, in particular, are important traits for the development of both trust in friends and strangers, agreeableness is related to trust in strangers.

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Narcolepsy is characterized by excessive daytime sleepiness and rapid eye movement (REM) sleep abnormalities, including cataplexy. The aim of this study was to assess REM sleep pressure and homeostasis in narcolepsy. Six patients with narcolepsy and six healthy controls underwent a REM sleep deprivation protocol, including one habituation, one baseline, two deprivation nights (D1, D2) and one recovery night. Multiple sleep latency tests (MSLTs) were performed during the day after baseline and after D2. During D1 and D2 REM sleep was prevented by awakening the subjects at the first polysomnographic signs of REM sleep for 2 min. Mean sleep latency and number of sleep-onset REM periods (SOREMs) were determined on all MSLT. More interventions were required to prevent REM sleep in narcoleptics compared with control subjects during D1 (57 ± 16 versus 24 ± 10) and D2 (87 ± 22 versus 35 ± 8, P = 0.004). Interventions increased from D1 to D2 by 46% in controls and by 53% in narcoleptics (P < 0.03). Selective REM sleep deprivation was successful in both controls (mean reduction of REM to 6% of baseline) and narcoleptics (11%). Both groups had a reduction of total sleep time during the deprivation nights (P = 0.03). Neither group had REM sleep rebound in the recovery night. Narcoleptics had, however, an increase in the number of SOREMs on MSLT (P = 0.005). There was no increase in the number of cataplexies after selective REM sleep deprivation. We conclude that: (i) REM sleep pressure is higher in narcoleptics; (ii) REM sleep homeostasis is similar in narcoleptics and controls; (iii) in narcoleptics selective REM sleep deprivation may have an effect on sleep propensity but not on cataplexy.