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1.
Context  Information on the school-age functioning and special health care needs of extremely low-birth-weight (ELBW, <1000 g) children is necessary to plan for medical and educational services. Objective  To examine neurosensory, developmental, and medical conditions together with the associated functional limitations and special health care needs of ELBW children compared with normal-birth-weight (NBW) term-born children (controls). Design, Setting, and Participants  A follow-up study at age 8 years of a cohort of 219 ELBW children born 1992 to 1995 (92% of survivors) and 176 NBW controls of similar sociodemographic status conducted in Cleveland, Ohio. Main Outcome Measures  Parent Questionnaire for Identifying Children with Chronic Conditions of 12 months or more and categorization of specific medical diagnoses and developmental disabilities based on examination of the children. Results  In logistic regression analyses adjusting for sociodemographic status and sex, ELBW children had significantly more chronic conditions than NBW controls, including functional limitations (64% vs 20%, respectively; odds ratio [OR], 8.1; 95% confidence interval [CI], 5.0-13.1; P<.001), compensatory dependency needs (48% vs 23%, respectively; OR, 3.0; 95% CI, 1.9-4.7; P<.001), and services above those routinely required by children (65% vs 27%, respectively; OR, 5.4; 95% CI, 3.4-8.5; P<.001). These differences remained significant when the 36 ELBW children with neurosensory impairments were excluded. Specific diagnoses and disabilities for ELBW vs NBW children included cerebral palsy (14% vs 0%, respectively; P<.001), asthma (21% vs 9%; OR, 3.0; 95% CI, 1.6-5.6; P = .001), vision of less than 20/200 (10% vs 3%; OR, 3.1; 95% CI, 1.2-7.8; P = .02), low IQ of less than 85 (38% vs 14%; OR, 4.5; 95% CI, 2.7-7.7; P<.001), limited academic skills (37% vs 15%; OR, 4.2; 95% CI, 2.5-7.3; P<.001), poor motor skills (47% vs 10%; OR, 7.8; 95% CI, 4.5-13.6; P<.001), and poor adaptive functioning (69% vs 34%; OR, 6.5; 95% CI, 4.0-10.6; P<.001). Conclusion  The ELBW survivors in school at age 8 years who were born in the 1990s have considerable long-term health and educational needs.   相似文献   

2.
Context  The outcome into school age of regional cohorts of children born in the 1990s with birth weights less than 1000 g (extremely low birth weight, ELBW) or earlier than 28 weeks' gestation (very preterm) is not known. Objective  To determine the cognitive, educational, and behavioral outcome of ELBW or very preterm infants born in the 1990s compared with normal birth weight (NBW) controls. Design  Regional cohort study. Setting  Victoria, Australia. Participants  The ELBW or very preterm cohort was composed of 298 consecutive survivors born during 1991-1992. The NBW cohort was composed of 262 randomly selected children with birth weights of more than 2499 g. Main Outcome Measures  Cognitive ability, educational progress, and behavioral problems. Results  The follow-up rates from birth to 8 years of age for survivors were 92.3% (275/298) for the ELBW or very preterm cohort and 85.1% (223/262) for the NBW cohort. The ELBW or very preterm children scored significantly below NBW controls on full-scale IQ (mean difference, –9.4; 95% confidence interval [CI], –12.1 to –6.7; P<.001) and indices of verbal comprehension (mean difference, –6.8; 95% CI, –9.5 to –4.2; P<.001), perceptual organization (mean difference, –9.9; 95% CI, –12.7 to –7.2; P<.001), freedom from distractibility (mean difference, –8.1; 95% CI, –10.8 to –5.5; P<.001), and processing speed (mean difference, –6.7; 95% CI, –9.4 to –4.0; P<.001). The ELBW or very preterm children performed significantly worse than the NBW cohort on tests of reading (mean difference, –6.7; 95% CI, –9.5 to –3.9; P<.001), spelling (mean difference, –5.6; 95% CI, –8.0 to –3.3; P<.001), and arithmetic (mean difference, –8.8; 95% CI, –11.3 to –6.2; P<.001). Attentional difficulties, internalizing behavior problems, and immature adaptive skills were more prevalent in the ELBW or very preterm cohort. Conclusion  School-aged ELBW or very preterm children born in the 1990s continue to display cognitive, educational, and behavioral impairments.   相似文献   

3.
Context  Although reperfusion therapy, aspirin, -blockers, and angiotensin-converting enzyme inhibitors reduce mortality when used early in patients with acute myocardial infarction (MI), mortality and morbidity remain high. No antithrombotic or newer antiplatelet drug has been shown to reduce mortality in acute MI. Objective  To evaluate the effects of reviparin, a low-molecular-weight heparin, when initiated early and given for 7 days in addition to usual therapy on the primary composite outcome of death, myocardial reinfarction, or strokes at 7 and 30 days. Design, Setting, and Patients  A randomized, double-blind, placebo-controlled trial (Clinical Trial of Reviparin and Metabolic Modulation in Acute Myocardial Infarction Treatment Evaluation [CREATE]) of 15 570 patients with ST-segment elevation or new left bundle-branch block, presenting within 12 hours of symptom onset at 341 hospitals in India and China from July 2001 through July 2004. Intervention  Reviparin or placebo subcutaneously twice daily for 7 days. Main Outcome Measure  Primary composite outcome of death, myocardial reinfarction, or stroke at 7 and 30 days. Results  The primary composite outcome was significantly reduced from 854 (11.0%) of 7790 patients in the placebo group to 745 (9.6%) of 7780 in the reviparin group (hazard ratio [HR], 0.87; 95% CI, 0.79-0.96; P = .005). These benefits persisted at 30 days (1056 [13.6%] vs 921 [11.8%] patients; HR, 0.87; 95% CI, 0.79-0.95; P = .001) with significant reductions in 30-day mortality (877 [11.3%] vs 766 [9.8%]; HR, 0.87; 95% CI, 0.79-0.96; P = .005) and reinfarction (199 [2.6%] vs 154 [2.0%]; HR, 0.77; 95% CI, 0.62-0.95; P = .01), and no significant differences in strokes (64 [0.8%] vs 80 [1.0%]; P = .19). Reviparin treatment was significantly better when it was initiated very early after symptom onset at 7 days (<2 hours: HR, 0.70; 95% CI, 0.52-0.96; P = .03; 30/1000 events prevented; 2 to <4 hours: HR, 0.81; 95% CI, 0.67-0.98; P = .03; 21/1000 events prevented; 4 to <8 hours: HR, 0.85; 95% CI, 0.73-0.99; P = .05; 16/1000 events prevented; and 8 hours: HR, 1.06; 95% CI, 0.86-1.30; P = .58; P = .04 for trend). There was an increase in life-threatening bleeding at 7 days with reviparin and placebo (17 [0.2%] vs 7 [0.1%], respectively; P = .07), but the absolute excess was small (1 more per 1000) vs reductions in the primary outcome (18 fewer per 1000) or mortality (15 fewer per 1000). Conclusions  In patients with acute ST-segment elevation or new left bundle-branch block MI, reviparin reduces mortality and reinfarction, without a substantive increase in overall stroke rates. There is a small absolute excess of life-threatening bleeding but the benefits outweigh the risks.   相似文献   

4.
Context  Despite many therapeutic advances, mortality in patients with acute ST-segment elevation myocardial infarction (STEMI) remains high. The role of additional antithrombotic agents is unclear, especially among patients not receiving reperfusion therapy. Objective  To evaluate the effect of fondaparinux, a factor Xa inhibitor, when initiated early and given for up to 8 days vs usual care (placebo in those in whom unfractionated heparin [UFH] is not indicated [stratum 1] or unfractionated heparin for up to 48 hours followed by placebo for up to 8 days [stratum 2]) in patients with STEMI. Design, Setting, and Participants  Randomized double-blind comparison of fondaparinux 2.5 mg once daily or control for up to 8 days in 12 092 patients with STEMI from 447 hospitals in 41 countries (September 2003-January 2006). From day 3 through day 9, all patients received either fondaparinux or placebo according to the original randomized assignment. Main Outcome Measures  Composite of death or reinfarction at 30 days (primary) with secondary assessments at 9 days and at final follow-up (3 or 6 months). Results  Death or reinfarction at 30 days was significantly reduced from 677 (11.2%) of 6056 patients in the control group to 585 (9.7%) of 6036 patients in the fondaparinux group (hazard ratio [HR], 0.86; 95% confidence interval [CI], 0.77-0.96; P = .008); absolute risk reduction, 1.5%; 95% CI, 0.4%-2.6%). These benefits were observed at 9 days (537 [8.9%] placebo vs 444 [7.4%] fondaparinux; HR, 0.83; 95% CI, 0.73-0.94; P = .003, and at study end (857 [14.8%] placebo vs 756 [13.4%] fondaparinux; HR, 0.88; 95% CI, 0.79-0.97; P = .008). Mortality was significantly reduced throughout the study. There was no heterogeneity of the effects of fondaparinux in the 2 strata by planned heparin use. However, there was no benefit in those undergoing primary percutaneous coronary intervention. In other patients in stratum 2, fondaparinux was superior to unfractionated heparin in preventing death or reinfarction at 30 days (HR, 0.82; 95% CI, 0.66-1.02; P = .08) and at study end (HR, 0.77; 95% CI, 0.64-0.93; P = .008). Significant benefits were observed in those receiving thrombolytic therapy (HR, 0.79; P = .003) and those not receiving any reperfusion therapy (HR, 0.80; P = .03). There was a tendency to fewer severe bleeds (79 for placebo vs 61 for fondaparinux; P = .13), with significantly fewer cardiac tamponade (48 vs 28; P = .02) with fondaparinux at 9 days. Conclusion  In patients with STEMI, particularly those not undergoing primary percutaneous coronary intervention, fondaparinux significantly reduces mortality and reinfarction without increasing bleeding and strokes. Trial Registration  ClinicalTrials.gov Identifier NCT00064428   相似文献   

5.
Context  Hypoxemia complicates the recovery of 30% to 50% of patients after abdominal surgery; endotracheal intubation and mechanical ventilation may be required in 8% to 10% of cases, increasing morbidity and mortality and prolonging intensive care unit and hospital stay. Objective  To determine the effectiveness of continuous positive airway pressure compared with standard treatment in preventing the need for intubation and mechanical ventilation in patients who develop acute hypoxemia after elective major abdominal surgery. Design and Setting  Randomized, controlled, unblinded study with concealed allocation conducted between June 2002 and November 2003 at 15 intensive care units of the Piedmont Intensive Care Units Network in Italy. Patients  Consecutive patients who developed severe hypoxemia after major elective abdominal surgery. The trial was stopped for efficacy after 209 patients had been enrolled. Interventions  Patients were randomly assigned to receive oxygen (n = 104) or oxygen plus continuous positive airway pressure (n = 105). Main Outcome Measures  The primary end point was incidence of endotracheal intubation; secondary end points were intensive care unit and hospital lengths of stay, incidence of pneumonia, infection and sepsis, and hospital mortality. Results  Patients who received oxygen plus continuous positive airway pressure had a lower intubation rate (1% vs 10%; P = .005; relative risk [RR], 0.099; 95% confidence interval [CI], 0.01-0.76) and had a lower occurrence rate of pneumonia (2% vs 10%, RR, 0.19; 95% CI, 0.04-0.88; P = .02), infection (3% vs 10%, RR, 0.27; 95% CI, 0.07-0.94; P = .03), and sepsis (2% vs 9%; RR, 0.22; 95% CI, 0.04-0.99; P = .03) than did patients treated with oxygen alone. Patients who received oxygen plus continuous positive airway pressure also spent fewer mean (SD) days in the intensive care unit (1.4 [1.6] vs 2.6 [4.2], P = .09) than patients treated with oxygen alone. The treatments did not affect the mean (SD) days that patients spent in the hospital (15 [13] vs 17 [15], respectively; P = .10). None of those treated with oxygen plus continuous positive airway pressure died in the hospital while 3 deaths occurred among those treated with oxygen alone (P = .12). Conclusion  Continuous positive airway pressure may decrease the incidence of endotracheal intubation and other severe complications in patients who develop hypoxemia after elective major abdominal surgery.   相似文献   

6.
Context  Although vascular brachytherapy is the only approved therapy for restenosis following bare-metal stent implantation, drug-eluting stents are now being used. Data on the relative merits of each are limited. Objective  To determine the safety and efficacy of the sirolimus-eluting stent compared with vascular brachytherapy for the treatment of patients with restenosis within a bare-metal stent. Design, Setting, and Patients  Prospective, multicenter, randomized trial of 384 patients with in-stent restenosis who were enrolled between February 2003 and July 2004 at 26 academic and community medical centers. Data presented represent all follow-up as of June 30, 2005. Interventions  Vascular brachytherapy (n = 125) or the sirolimus-eluting stent (n = 259). Main Outcome Measure  Target vessel failure (cardiac death, myocardial infarction, or target vessel revascularization) at 9 months postprocedure. Results  Baseline patient characteristics were well matched. Lesion length was similar between vascular brachytherapy and sirolimus-eluting stent patients (mean [SD], 16.76 [8.55] mm vs 17.22 [7.97] mm, respectively; P = .61). Procedural success was 99.2% (124/125) in the vascular brachytherapy group and 97.3% (250/257) in the sirolimus-eluting stent group (P = .28). The rate of target vessel failure was 21.6% (27/125) with vascular brachytherapy and 12.4% (32/259) with the sirolimus-eluting stent (relative risk [RR], 1.7; 95% confidence interval [CI], 1.1-2.8; P = .02). Target lesion revascularization was required in 19.2% (24/125) of the vascular brachytherapy group and 8.5% (22/259) of the sirolimus-eluting stent group (RR, 2.3 [95% CI, 1.3-3.9]; P = .004). At follow-up angiography, the rate of binary angiographic restenosis for the analysis segment was 29.5% (31/105) for the vascular brachytherapy group and 19.8% (45/227) for the sirolimus-eluting stent group (RR, 1.5 [95% CI, 1.0-2.2]; P = .07). Compared with the vascular brachytherapy group, minimal lumen diameter was larger in the sirolimus-eluting stent group at 6-month follow-up (mean [SD], 1.52 [0.63] mm vs 1.80 [0.63] mm; P<.001), reflecting greater net lumen gain in the analysis segment (0.68 [0.60] vs 1.0 [0.61] mm; P<.001) due to stenting and no edge restenosis. Conclusion  Sirolimus-eluting stents result in superior clinical and angiographic outcomes compared with vascular brachytherapy for the treatment of restenosis within a bare-metal stent. Trial Registration  ClinicalTrials.gov Identifier: NCT00231257   相似文献   

7.
Context  Atrial tachyarrhythmias after cardiac surgery are associated with adverse outcomes and increased costs. Previous trials of amiodarone prophylaxis, while promising, were relatively small and yielded conflicting results. Objective  To determine whether a brief perioperative course of oral amiodarone is an effective and safe prophylaxis for atrial tachyarrhythmias after cardiac surgery overall and in important subgroups. Design, Setting, and Patients  Double-blind randomized controlled trial of 601 patients listed for nonemergent coronary artery bypass graft (CABG) surgery and/or valve replacement/repair surgery between February 1, 1999, and September 26, 2003, at a tertiary care hospital. The patients were followed up for 1 year. Intervention  Oral amiodarone (10 mg/kg daily) or placebo administered 6 days prior to surgery through 6 days after surgery (13 days). Randomization was stratified for subgroups defined by age, type of surgery, and use of preoperative -blockers. Main Outcome Measure  Incidence of atrial tachyarrhythmias lasting 5 minutes or longer that prompted therapy by the sixth postoperative day. Results  Atrial tachyarrhythmias occurred in fewer amiodarone patients (48/299; 16.1%) than in placebo patients (89/302; 29.5%) overall (hazard ratio [HR], 0.52; 95% confidence interval [CI], 0.34-0.69; P<.001); in patients younger than 65 years (19 [11.2%] vs 36 [21.1%]; HR, 0.51 [95% CI, 0.28-0.94]; P = .02); in patients aged 65 years or older (28 [21.7%] vs 54 [41.2%]; HR, 0.45 [95% CI, 0.27-0.75]; P<.001); in patients who had CABG surgery only (22 [11.3%] vs 46 [23.6%]; HR, 0.45 [95% CI, 0.26-0.79]; P = .002); in patients who had valve replacement/repair surgery with or without CABG surgery (25 [23.8%] vs 44 [44.1%]; HR, 0.51 [95% CI, 0.31-0.84; P = .008); in patients who received preoperative -blocker therapy (27 [15.3%] vs 42 [25.0%]; HR, 0.58 [95% CI, 0.34-0.99]; P = .03); and in patients who did not receive preoperative -blocker therapy (20 [16.3%] vs 48 [35.8%]; HR, 0.40 [95% CI, 0.22-0.71]; P<.001), respectively. Postoperative sustained ventricular tachyarrhythmias occurred less frequently in amiodarone patients (1/299; 0.3%) than in placebo patients (8/302; 2.6%) (P = .04). Dosage reductions of blinded therapy were more common in amiodarone patients (34/299; 11.4%) than in placebo patients (16/302; 5.3%) (P = .008). There were no differences in serious postoperative complications, in-hospital mortality, or readmission to the hospital within 6 months of discharge or in 1-year mortality. Conclusion  Oral amiodarone prophylaxis of atrial tachyarrhythmias after cardiac surgery is effective and may be safe overall and in important patient subgroups. Clinical Trials Registration  ClinicalTrials.gov Identifier: NCT00251706   相似文献   

8.
Context  Recent studies have suggested a link between inhaled particulate matter exposure in urban areas and susceptibility to cardiovascular events; however, the precise mechanisms remain to be determined. Objective  To test the hypothesis that subchronic exposure to environmentally relevant particulate matter, even at low concentrations, potentiates atherosclerosis and alters vasomotor tone in a susceptible disease model. Design, Setting, and Participants  Between July 21, 2004, and January 12, 2005, 28 apolipoprotein E–/– (apoE–/–) mice were, based on randomized assignments, fed with normal chow or high-fat chow and exposed to concentrated ambient particles of less than 2.5 µm (PM2.5) or filtered air (FA) in Tuxedo, NY, for 6 hours per day, 5 days per week for a total of 6 months. Main Outcome Measures  Composite atherosclerotic plaque in the thoracic and abdominal aorta and vasomotor tone changes. Results  In the high-fat chow group, the mean (SD) composite plaque area of PM2.5 vs FA was 41.5% (9.8%) vs 26.2% (8.6%), respectively (P<.001); and in the normal chow group, the composite plaque area was 19.2% (13.1%) vs 13.2% (8.1%), respectively (P = .15). Lipid content in the aortic arch measured by oil red-O staining revealed a 1.5-fold increase in mice fed the high-fat chow and exposed to PM2.5 vs FA (30.0 [8.2] vs 20.0 [7.0]; 95% confidence interval [CI], 1.21-1.83; P = .02). Vasoconstrictor responses to phenylephrine and serotonin challenge in the thoracic aorta of mice fed high-fat chow and exposed to PM2.5 were exaggerated compared with exposure to FA (mean [SE], 134.2% [5.2%] vs 100.9% [2.9%], for phenylephrine, and 156.0% [5.6%] vs 125.1% [7.5%], for serotonin; both P = .03); relaxation to the endothelium-dependent agonist acetylcholine was attenuated (mean [SE] of half-maximal dose for dilation, 8.9 [0.2] x 10-8 vs 4.3 [0.1] x 10-8, respectively; P = .04). Mice fed high-fat chow and exposed to PM2.5 demonstrated marked increases in macrophage infiltration, expression of the inducible isoform of nitric oxide synthase, increased generation of reactive oxygen species, and greater immunostaining for the protein nitration product 3-nitrotyrosine (all P<.001). Conclusion  In an apoE–/– mouse model, long-term exposure to low concentration of PM2.5 altered vasomotor tone, induced vascular inflammation, and potentiated atherosclerosis.   相似文献   

9.
Pereira MA  Swain J  Goldfine AB  Rifai N  Ludwig DS 《JAMA》2004,292(20):2482-2490
Context  Weight loss elicits physiological adaptations relating to energy intake and expenditure that antagonize ongoing weight loss. Objective  To test whether dietary composition affects the physiological adaptations to weight loss, as assessed by resting energy expenditure. Design, Study, and Participants  A randomized parallel-design study of 39 overweight or obese young adults aged 18 to 40 years who received an energy-restricted diet, either low–glycemic load or low-fat. Participants were studied in the General Clinical Research Centers of the Brigham and Women’s Hospital and the Children’s Hospital, Boston, Mass, before and after 10% weight loss. The study was conducted from January 4, 2001, to May 6, 2003. Main Outcome Measures  Resting energy expenditure measured in the fasting state by indirect calorimetry, body composition by dual-energy x-ray absorptiometry, cardiovascular disease risk factors, and self-reported hunger. Results  Resting energy expenditure decreased less with the low–glycemic load diet than with the low-fat diet, expressed in absolute terms (mean [SE], 96 [24] vs 176 [27] kcal/d; P = .04) or as a proportion (5.9% [1.5%] vs 10.6% [1.7%]; P = .05). Participants receiving the low–glycemic load diet reported less hunger than those receiving the low-fat diet (P = .04). Insulin resistance (P = .01), serum triglycerides (P = .01), C-reactive protein (P = .03), and blood pressure (P = .07 for both systolic and diastolic) improved more with the low–glycemic load diet. Changes in body composition (fat and lean mass) in both groups were very similar (P = .85 and P = .45, respectively). Conclusions  Changes in dietary composition within prevailing norms can affect physiological adaptations that defend body weight. Reduction in glycemic load may aid in the prevention or treatment of obesity, cardiovascular disease, and diabetes mellitus.   相似文献   

10.
Counsell SR  Callahan CM  Clark DO  Tu W  Buttar AB  Stump TE  Ricketts GD 《JAMA》2007,298(22):2623-2633
Steven R. Counsell, MD; Christopher M. Callahan, MD; Daniel O. Clark, PhD; Wanzhu Tu, PhD; Amna B. Buttar, MD, MS; Timothy E. Stump, MS; Gretchen D. Ricketts, BSW

JAMA. 2007;298(22):2623-2633.

Context  Low-income seniors frequently have multiple chronic medical conditions for which they often fail to receive the recommended standard of care.

Objectives  To test the effectiveness of a geriatric care management model on improving the quality of care for low-income seniors in primary care.

Design, Setting, and Patients  Controlled clinical trial of 951 adults 65 years or older with an annual income less than 200% of the federal poverty level, whose primary care physicians were randomized from January 2002 through August 2004 to participate in the intervention (474 patients) or usual care (477 patients) in community-based health centers.

Intervention  Patients received 2 years of home-based care management by a nurse practitioner and social worker who collaborated with the primary care physician and a geriatrics interdisciplinary team and were guided by 12 care protocols for common geriatric conditions.

Main Outcome Measures  The Medical Outcomes 36-Item Short-Form (SF-36) scales and summary measures; instrumental and basic activities of daily living (ADLs); and emergency department (ED) visits not resulting in hospitalization and hospitalizations.

Results  Intention-to-treat analysis revealed significant improvements for intervention patients compared with usual care at 24 months in 4 of 8 SF-36 scales: general health (0.2 vs –2.3, P = .045), vitality (2.6 vs –2.6, P < .001), social functioning (3.0 vs –2.3, P = .008), and mental health (3.6 vs –0.3, P = .001); and in the Mental Component Summary (2.1 vs –0.3, P < .001). No group differences were found for ADLs or death. The cumulative 2-year ED visit rate per 1000 was lower in the intervention group (1445 [n = 474] vs 1748 [n = 477], P = .03) but hospital admission rates per 1000 were not significantly different between groups (700 [n = 474] vs 740 [n = 477], P = .66). In a predefined group at high risk of hospitalization (comprising 112 intervention and 114 usual-care patients), ED visit and hospital admission rates were lower for intervention patients in the second year (848 [n = 106] vs 1314 [n = 105]; P = .03 and 396 [n = 106] vs 705 [n = 105]; P = .03, respectively).

Conclusions  Integrated and home-based geriatric care management resulted in improved quality of care and reduced acute care utilization among a high-risk group. Improvements in health-related quality of life were mixed and physical function outcomes did not differ between groups. Future studies are needed to determine whether more specific targeting will improve the program's effectiveness and whether reductions in acute care utilization will offset program costs.

Trial Registration  clinicaltrials.gov Identifier: NCT00182962

  相似文献   


11.
Patent foramen ovale and high-altitude pulmonary edema   总被引:2,自引:0,他引:2  
Allemann Y  Hutter D  Lipp E  Sartori C  Duplain H  Egli M  Cook S  Scherrer U  Seiler C 《JAMA》2006,296(24):2954-2958
Context  Individuals susceptible to high-altitude pulmonary edema (HAPE) are characterized by exaggerated pulmonary hypertension and arterial hypoxemia at high altitude, but the underlying mechanism is incompletely understood. Anecdotal evidence suggests that shunting across a patent foramen ovale (PFO) may exacerbate hypoxemia in HAPE. Objective  We hypothesized that PFO is more frequent in HAPE-susceptible individuals and may contribute to more severe arterial hypoxemia at high altitude. Design, Setting, and Participants  Case-control study of 16 HAPE-susceptible participants and 19 mountaineers resistant to this condition (repeated climbing to peaks above 4000 m and no symptoms of HAPE). Main Outcome Measures  Presence of PFO determined by transesophageal echocardiography, estimated pulmonary artery pressure by Doppler echocardiography, and arterial oxygen saturation measured by pulse oximetry in HAPE-susceptible and HAPE-resistant participants at low (550 m) and high altitude (4559 m). Results  The frequency of PFO was more than 4 times higher in HAPE-susceptible than in HAPE-resistant participants, both at low altitude (56% vs 11%, P = .004; odds ratio [OR], 10.9 [95% confidence interval {CI}, 1.9-64.0]) and high altitude (69% vs 16%, P = .001; OR, 11.7 [95% CI, 2.3-59.5]). At high altitude, mean (SD) arterial oxygen saturation prior to the onset of pulmonary edema was significantly lower in HAPE-susceptible participants than in the control group (73% [10%] vs 83% [7%], P = .001). Moreover, in the HAPE-susceptible group, participants with a large PFO had more severe arterial hypoxemia (65% [6%] vs 77% [8%], P = .02) than those with smaller or no PFO. Conclusions  Patent foramen ovale was roughly 4 times more frequent in HAPE-susceptible mountaineers than in participants resistant to this condition. At high altitude, HAPE-susceptible participants with a large PFO had more severe hypoxemia. We speculate that at high altitude, a large PFO may contribute to exaggerated arterial hypoxemia and facilitate HAPE.   相似文献   

12.
Windish DM  Huot SJ  Green ML 《JAMA》2007,298(9):1010-1022
Context  Physicians depend on the medical literature to keep current with clinical information. Little is known about residents' ability to understand statistical methods or how to appropriately interpret research outcomes. Objective  To evaluate residents' understanding of biostatistics and interpretation of research results. Design, Setting, and Participants  Multiprogram cross-sectional survey of internal medicine residents. Main Outcome Measure  Percentage of questions correct on a biostatistics/study design multiple-choice knowledge test. Results  The survey was completed by 277 of 367 residents (75.5%) in 11 residency programs. The overall mean percentage correct on statistical knowledge and interpretation of results was 41.4% (95% confidence interval [CI], 39.7%-43.3%) vs 71.5% (95% CI, 57.5%-85.5%) for fellows and general medicine faculty with research training (P < .001). Higher scores in residents were associated with additional advanced degrees (50.0% [95% CI, 44.5%-55.5%] vs 40.1% [95% CI, 38.3%-42.0%]; P < .001); prior biostatistics training (45.2% [95% CI, 42.7%-47.8%] vs 37.9% [95% CI, 35.4%-40.3%]; P = .001); enrollment in a university-based training program (43.0% [95% CI, 41.0%-45.1%] vs 36.3% [95% CI, 32.6%-40.0%]; P = .002); and male sex (44.0% [95% CI, 41.4%-46.7%] vs 38.8% [95% CI, 36.4%-41.1%]; P = .004). On individual knowledge questions, 81.6% correctly interpreted a relative risk. Residents were less likely to know how to interpret an adjusted odds ratio from a multivariate regression analysis (37.4%) or the results of a Kaplan-Meier analysis (10.5%). Seventy-five percent indicated they did not understand all of the statistics they encountered in journal articles, but 95% felt it was important to understand these concepts to be an intelligent reader of the literature. Conclusions  Most residents in this study lacked the knowledge in biostatistics needed to interpret many of the results in published clinical research. Residency programs should include more effective biostatistics training in their curricula to successfully prepare residents for this important lifelong learning skill.   相似文献   

13.
Context  Heart failure causes more than 1 million US hospitalizations yearly, mostly related to congestion. Tolvaptan, an oral, nonpeptide, selective vasopressin V2-receptor antagonist, shows promise in this condition. Objective  To evaluate short-term effects of tolvaptan when added to standard therapy in patients hospitalized with heart failure. Design, Setting, and Patients  Two identical prospective, randomized, double-blind, placebo-controlled trials at 359 sites in North America, South America, and Europe were conducted during the inpatient period of the Efficacy of Vasopressin Antagonism in Heart Failure Outcome Study With Tolvaptan (EVEREST) between October 7, 2003, and February 3, 2006. A total of 2048 (trial A) and 2085 (trial B) patients hospitalized with heart failure and congestion were studied. Intervention  Patients were randomized to receive either tolvaptan (30 mg/d) or matching placebo, within 48 hours of admission. Main Outcome Measures  Primary end point was a composite of changes in global clinical status based on a visual analog scale and body weight at day 7 or discharge if earlier. Secondary end points included dyspnea (day 1), global clinical status (day 7 or discharge), body weight (days 1 and 7 or discharge), and peripheral edema (day 7 or discharge). Results  Rank sum analysis of the composite primary end point showed greater improvement with tolvaptan vs placebo (trial A, mean [SD], 1.06 [0.43] vs 0.99 [0.44]; and trial B, 1.07 [0.42] vs 0.97 [0.43]; both trials P<.001). Mean (SD) body weight reduction was greater with tolvaptan on day 1 (trial A, 1.71 [1.80] vs 0.99 [1.83] kg; P<.001; and trial B, 1.82 [2.01] vs 0.95 [1.85] kg; P<.001) and day 7 or discharge (trial A, 3.35 [3.27] vs 2.73 [3.34] kg; P<.001; and trial B, 3.77 [3.59] vs 2.79 [3.46] kg; P<.001), whereas improvements in global clinical status were not different between groups. More patients receiving tolvaptan (684 [76.7%] and 678 [72.1%] for trial A and trial B, respectively) vs patients receiving placebo (646 [70.6%] and 597 [65.3%], respectively) reported improvement in dyspnea at day 1 (both trials P<.001). Edema at day 7 or discharge improved significantly with tolvaptan in trial B (P = .02) but did not reach significance in trial A (P = .07). Serious adverse event frequencies were similar between groups, without excess renal failure or hypotension. Conclusion  In patients hospitalized with heart failure, oral tolvaptan in addition to standard therapy including diuretics improved many, though not all, heart failure signs and symptoms, without serious adverse events. Trial Registration  clinicaltrials.gov Identifier: NCT00071331   相似文献   

14.
Context  Certificate of need regulations were enacted to control health care costs by limiting unnecessary expansion of services. While many states have repealed certificate of need regulations in recent years, few analyses have examined relationships between certificate of need regulations and outcomes of care. Objective  To compare rates of coronary revascularization and mortality after acute myocardial infarction in states with and without certificate of need regulations. Design, Setting, and Participants  Retrospective cohort study of 1 139 792 Medicare beneficiaries aged 68 years or older with AMI who were admitted to 4587 US hospitals during 2000-2003. Main Outcome Measures  Thirty-day risk-adjusted rates of coronary revascularization with either coronary artery bypass graft surgery or percutaneous coronary intervention and 30-day all-cause mortality. Results  The 624 421 patients in states with certificate of need regulations were less likely to be admitted to hospitals with coronary revascularization services (321 573 [51.5%] vs 323 695 [62.8%]; P<.001) or to undergo revascularization at the admitting hospital (163 120 [26.1%] vs 163 877 [31.8%]; P<.001) than patients in states without certificates of need but were more likely to undergo revascularization at a transfer hospital (73 379 [11.7%] vs 45 907 [8.9%]; P<.001). Adjusting for demographic and clinical risk factors, patients in states with highly and moderately stringent certificate of need regulations, respectively, were less likely to undergo revascularization within the first 2 days (adjusted hazard ratios, 0.68; 95% confidence interval [CI], 0.54-0.87; P = .002 and 0.80; 95% CI, 0.71-0.90; P<.001) relative to patients in states without certificates of need, although no differences in the likelihood of revascularization were observed during days 3 through 30. Unadjusted 30-day mortality was similar in states with and without certificates of need (109 304 [17.5%] vs 90 104 [17.5%]; P = .76), as was adjusted mortality (odds ratio, 1.00; 95% CI, 0.97-1.03; P = .90). Conclusions  Patients with acute myocardial infarction were less likely to be admitted to hospitals offering coronary revascularization and to undergo early revascularization in states with certificate of need regulations. However, differences in the availability and use of revascularization therapies were not associated with mortality.   相似文献   

15.
Context  Abdominal obesity is associated with metabolic abnormalities and increased risk of atherosclerotic cardiovascular disease. However, no obesity management strategy has demonstrated the ability to slow progression of coronary disease. Objective  To determine whether weight loss and metabolic effects of the selective cannabinoid type 1 receptor antagonist rimonabant reduces progression of coronary disease in patients with abdominal obesity and the metabolic syndrome. Design, Setting, and Patients  Randomized, double-blinded, placebo-controlled, 2-group, parallel-group trial (enrollment December 2004-December 2005) comparing rimonabant with placebo in 839 patients at 112 centers in North America, Europe, and Australia. Interventions  Patients received dietary counseling, were randomized to receive rimonabant (20 mg daily) or matching placebo, and underwent coronary intravascular ultrasonography at baseline (n = 839) and study completion (n = 676). Main Outcome Measures  The primary efficacy parameter was change in percent atheroma volume (PAV); the secondary efficacy parameter was change in normalized total atheroma volume (TAV). Results  In the rimonabant vs placebo groups, PAV (95% confidence interval [CI]) increased 0.25% (–0.04% to 0.54%) vs 0.51% (0.22% to 0.80%) (P = .22), respectively, and TAV decreased 2.2 mm3 (–4.09 to –0.24) vs an increase of 0.88 mm3 (–1.03 to 2.79) (P = .03). In the rimonabant vs placebo groups, imputing results based on baseline characteristics for patients not completing the trial, PAV increased 0.25% (–0.04% to 0.55%) vs 0.57% (0.29% to 0.84%) (P = .13), and TAV decreased 1.95 mm3 (–3.8 to –0.10) vs an increase of 1.19 mm3 (–0.73 to 3.12) (P = .02). Rimonabant-treated patients had a larger reduction in body weight (4.3 kg [–5.1 to –3.5] vs 0.5 kg [–1.3 to 0.3]) and greater decrease in waist circumference (4.5 cm [–5.4 to –3.7] vs 1.0 cm [–1.9 to –0.2]) (P < .001 for both comparisons). In the rimonabant vs placebo groups, high-density lipoprotein cholesterol levels increased 5.8 mg/dL (4.9 to 6.8) (22.4%) vs 1.8 mg/dL (0.9 to 2.7) (6.9%) (P < .001), and median triglyceride levels decreased 24.8 mg/dL (–35.4 to –17.3) (20.5%) vs 8.9 mg/dL (–14.2 to –1.8) (6.2%) (P < .001). Rimonabant-treated patients had greater decreases in high-sensitivity C-reactive protein (1.3 mg/dL [–1.7 to –1.2] [50.3%] vs 0.9 mg/dL [–1.4 to –0.5] [30.9%]) and less increase in glycated hemoglobin levels (0.11% [0.02% to 0.20%] vs 0.40% [0.31% to 0.49%]) (P < .001 for both comparisons). Psychiatric adverse effects were more common in the rimonabant group (43.4% vs 28.4%, P < .001). Conclusions  After 18 months of treatment, the study failed to show an effect for rimonabant on disease progression for the primary end point (PAV) but showed a favorable effect on the secondary end point (TAV). Determining whether rimonabant is useful in management of coronary disease will require additional imaging and outcomes trials, which are currently under way. Trial Registration  clinicaltrials.gov Identifier: NCT00124332   相似文献   

16.
Context  Glucose-insulin-potassium (GIK) infusion is a widely applicable, low-cost therapy that has been postulated to improve mortality in patients with acute ST-segment elevation myocardial infarction (STEMI). Given the potential global importance of GIK infusion, a large, adequately powered randomized trial is required to determine the effect of GIK on mortality in patients with STEMI. Objective  To determine the effect of high-dose GIK infusion on mortality in patients with STEMI. Design, Setting, and Participants  Randomized controlled trial conducted in 470 centers worldwide among 20 201 patients with STEMI who presented within 12 hours of symptom onset. The mean age of patients was 58.6 years, and evidence-based therapies were commonly used. Intervention  Patients were randomly assigned to receive GIK intravenous infusion for 24 hours plus usual care (n = 10 091) or to receive usual care alone (controls; n = 10 110). Main Outcome Measures  Mortality, cardiac arrest, cardiogenic shock, and reinfarction at 30 days after randomization. Results  At 30 days, 976 control patients (9.7%) and 1004 GIK infusion patients (10.0%) died (hazard ratio [HR], 1.03; 95% confidence interval [CI], 0.95-1.13; P = .45). There were no significant differences in the rates of cardiac arrest (1.5% [151/10 107] in control and 1.4% [139/10 088] in GIK infusion; HR, 0.93; 95% CI, 0.74-1.17; P = .51), cardiogenic shock (6.3% [640/10 107] vs 6.6% [667/10 088]; HR, 1.05; 95% CI, 0.94-1.17; P = .38), or reinfarction (2.4% [246/10 107] vs 2.3% [236/10 088]; HR, 0.98; 95% CI, 0.82-1.17; P = .81). The rates of heart failure at 7 days after randomization were also similar between the groups (16.9% [1711/10 107] vs 17.1% [1721/10 088]; HR, 1.01; 95% CI, 0.95-1.08; P = .72). The lack of benefit of GIK infusion on mortality was consistent in prespecified subgroups, including in those with and without diabetes, in those presenting with and without heart failure, in those presenting early and later after symptom onset, and in those receiving and not receiving reperfusion therapy (thrombolysis or primary percutaneous coronary intervention). Conclusion  In this large, international randomized trial, high-dose GIK infusion had a neutral effect on mortality, cardiac arrest, and cardiogenic shock in patients with acute STEMI.   相似文献   

17.
Context  Aortic stiffness is increased in Marfan syndrome contributing to aortic dilatation and rupture, the major cause of premature death in this population. Angiotensin-converting enzyme inhibitors have been shown to reduce arterial stiffness. Objective  To determine whether perindopril therapy reduces aortic stiffness and attenuates aortic dilatation in patients with Marfan syndrome. Design, Setting, and Participants  A randomized, double-blind, placebo-controlled trial of 17 patients with Marfan syndrome (mean [SD], 33 [6] years) taking standard -blocker therapy, initiated in January 2004 and completed in September 2006, at Alfred Hospital Marfan Syndrome Clinic, Melbourne, Australia. Intervention  Patients were administered 8 mg/d of perindopril (n = 10) or placebo (n = 7) for 24 weeks. Main Outcome Measures  Indices of arterial stiffness were assessed via systemic arterial compliance, and central and peripheral pulse wave velocities. Aortic root diameters were assessed at 4 sites via transthoracic echocardiography. Results  Perindopril reduced arterial stiffness as indicated by increased systemic arterial compliance (mean [SEM], 0.33 [0.01] mL/mm Hg at baseline to 0.54 [0.04] mL/mm Hg at 24 weeks in perindopril group vs 0.30 [0.01] mL/mm Hg to 0.29 [0.01] mL/mm Hg in placebo group, P = .004), and reduced central (7.6 [0.4] m/s to 5.9 [0.3] m/s in perindopril group, P < .001 vs placebo) and peripheral (10.9 [0.4] m/s to 8.7 [0.4] m/s in perindopril group, P < .001 vs placebo) pulse wave velocities. In addition, perindopril significantly reduced aortic root diameters relative to placebo in both end-systole and end-diastole (P<.01 to P < .001 for all comparisons between groups). Although perindopril marginally reduced mean arterial pressure (from 81 [2] mm Hg to 80 [1] mm Hg in perindopril group vs 83 [2] mm Hg to 84 [3] mm Hg in placebo group, P = .004), the observed changes in both stiffness and left ventricular outflow tract diameter remained significant when mean arterial pressure was included as a covariate. Transforming growth factor (TGF-), which contributes to aortic degeneration in Marfan syndrome, was reduced by perindopril compared with placebo in both latent (59 [6] ng/mL to 45 [3] ng/mL in perindopril group, P = .01 vs placebo) and active (46 [2] ng/mL to 42 [1] ng/mL in perindopril group, P = .02 vs placebo) forms. Conclusions  Perindopril reduced both aortic stiffness and aortic root diameter in patients with Marfan syndrome taking standard -blocker therapy, possibly through attenuation of TGF- signaling. Large clinical trials are needed to assess the clinical benefit of angiotensin II blockade in Marfan syndrome. Trial Registration  clinicaltrials.gov Identifier: NCT00485368   相似文献   

18.
Context  The effect of antihypertensive drugs on cardiovascular events in patients with coronary artery disease (CAD) and normal blood pressure remains uncertain. Objective  To compare the effects of amlodipine or enalapril vs placebo on cardiovascular events in patients with CAD. Design, Setting, and Participants  Double-blind, randomized, multicenter, 24-month trial (enrollment April 1999-April 2002) comparing amlodipine or enalapril with placebo in 1991 patients with angiographically documented CAD (>20% stenosis by coronary angiography) and diastolic blood pressure <100 mm Hg. A substudy of 274 patients measured atherosclerosis progression by intravascular ultrasound (IVUS). Interventions  Patients were randomized to receive amlodipine, 10 mg; enalapril, 20 mg; or placebo. IVUS was performed at baseline and study completion. Main Outcome Measures  The primary efficacy parameter was incidence of cardiovascular events for amlodipine vs placebo. Other outcomes included comparisons of amlodipine vs enalapril and enalapril vs placebo. Events included cardiovascular death, nonfatal myocardial infarction, resuscitated cardiac arrest, coronary revascularization, hospitalization for angina pectoris, hospitalization for congestive heart failure, fatal or nonfatal stroke or transient ischemic attack, and new diagnosis of peripheral vascular disease. The IVUS end point was change in percent atheroma volume. Results  Baseline blood pressure averaged 129/78 mm Hg for all patients; it increased by 0.7/0.6 mm Hg in the placebo group and decreased by 4.8/2.5 mm Hg and 4.9/2.4 mm Hg in the amlodipine and enalapril groups, respectively (P<.001 for both vs placebo). Cardiovascular events occurred in 151 (23.1%) placebo-treated patients, in 110 (16.6%) amlodipine-treated patients (hazard ratio [HR], 0.69; 95% CI, 0.54-0.88 [P = .003]), and in 136 (20.2%) enalapril-treated patients (HR, 0.85; 95% CI, 0.67-1.07 [P = .16]. Primary end point comparison for enalapril vs amlodipine was not significant (HR, 0.81; 95% CI, 0.63-1.04 [P = .10]). The IVUS substudy showed a trend toward less progression of atherosclerosis in the amlodipine group vs placebo (P = .12), with significantly less progression in the subgroup with systolic blood pressures greater than the mean (P = .02). Compared with baseline, IVUS showed progression in the placebo group (P<.001), a trend toward progression in the enalapril group (P = .08), and no progression in the amlodipine group (P = .31). For the amlodipine group, correlation between blood pressure reduction and progression was r = 0.19, P = .07. Conclusions  Administration of amlodipine to patients with CAD and normal blood pressure resulted in reduced adverse cardiovascular events. Directionally similar, but smaller and nonsignificant, treatment effects were observed with enalapril. For amlodipine, IVUS showed evidence of slowing of atherosclerosis progression.   相似文献   

19.
Context  Renal dysfunction is a complication of coronary artery bypass graft (CABG) surgery performed with cardiopulmonary bypass (CPB) that is associated with increased morbidity and mortality. N-acetylcysteine, an antioxidant and vasodilator, counteracts renal ischemia and hypoxia. Objective  To determine whether perioperative intravenous (IV) N-acetylcysteine preserves renal function in high-risk patients undergoing CABG surgery with CPB compared with placebo. Design, Setting, and Patients  Randomized, quadruple blind, placebo-controlled trial (October 2003-September 2004) in operating rooms and general intensive care units (ICUs) of 2 Ontario tertiary care centers. The 295 patients required elective or urgent CABG and had at least 1 of the following: preexisting renal dysfunction, at least 70 years old, diabetes mellitus, impaired left ventricular function, or undergoing concomitant valve or redo surgery. Interventions  Patients received 4 (2 intraoperative and 2 postoperative) doses of IV N-acetylcysteine (600 mg) (n = 148) or placebo (n = 147) over 24 hours. Main Outcome Measures  The primary outcome was the proportion of patients developing postoperative renal dysfunction, defined by an increase in serum creatinine level greater than 0.5 mg/dL (44 µmol/L) or a 25% increase from baseline within the first 5 postoperative days. Secondary outcomes included postoperative interventions and complications, the requirement for renal replacement therapy (RRT), adverse events, hospital mortality, and ICU and hospital length of stay. Results  There was no difference in the proportion of patients with postoperative renal dysfunction (29.7% vs 29.0%, P = .89; relative risk [RR], 1.03 [95% confidence interval {CI}, 0.72-1.46]) in the N-acetylcysteine and placebo groups, respectively. We noted nonsignificant differences in postoperative interventions and complications, the need for RRT (0.7% vs 2.1%; P = .37), total (6.1% vs 9.6%; P = .26) and serious adverse events, hospital mortality (3.4% vs 2.7%; P>.99), and ICU and hospital length of stay between the N-acetylcysteine and placebo groups. A post hoc subgroup analysis of patients (baseline creatinine level >1.4 mg/dL [120 µmol/L]) showed a nonsignificant trend toward fewer patients experiencing postoperative renal dysfunction in the N-acetylcysteine group compared with the placebo group (25.0% vs 37.1%; P = .29). Conclusions  N-acetylcysteine did not prevent postoperative renal dysfunction, interventions, complications, or mortality in high-risk patients undergoing CABG surgery with CPB. Further research is required to identify CABG patients at risk for postoperative renal events, valid markers of renal dysfunction, and to establish renal thresholds associated with important clinical outcomes.   相似文献   

20.
Context  The benefits of abciximab in patients with ST-segment elevation myocardial infarction (STEMI) are still a matter of debate. Objective  To combine data from all randomized trials conducted with abciximab in STEMI. Data Sources  Formal searches of electronic databases (MEDLINE, PubMed) from from January 1990 to December 2004. Study Selection  We examined all completed, published, randomized trials of abciximab in STEMI. The following key words were used for study selection: randomized trial, myocardial infarction, reperfusion, primary angioplasty, facilitated angioplasty, stenting, fibrinolysis, IIb-IIIa inhibitors, and abciximab. Data Extraction  Information on study design, type and dosage of drugs, inclusion and exclusion criteria, number of patients, and clinical outcome was extracted by 2 investigators. Disagreements were resolved by consensus. Data Synthesis  Eleven trials were analyzed, involving 27115 patients (12 602 [46.5%] in the abciximab group, 14 513 [53.5%] in the control group). When compared with the control group, abciximab was associated with a significant reduction in short-term (30 days) mortality (2.4% vs 3.4%, P = .047) and long-term (6-12 months) mortality (4.4% vs 6.2%, P = .01) in patients undergoing primary angioplasty but not in those treated with fibrinolysis or in all trials combined. Abciximab was associated with a significant reduction in 30-day reinfarction, both in all trials combined (2.1% vs 3.3%, P<.001), in primary angioplasty (1.0% vs 1.9%, P = .03), and in fibrinolysis trials (2.3% vs 3.6%, P<.001). Abciximab did not result in an increased risk of intracranial bleeding (0.61% vs 0.62%, P = .62) but was associated with an increased risk of major bleeding complications when combined with fibrinolysis (5.2% vs 3.1%, P<.001) but not with primary angioplasty (4.7% vs 4.1%, P = .36). Conclusions  This meta-analysis shows that, when compared with the control group, adjunctive abciximab for STEMI is associated with a significant reduction in 30-day and long-term mortality in patients treated with primary angioplasty but not in those receiving fibrinolysis. The 30-day reinfarction rate is significantly reduced in patients treated with either fibrinolysis or primary angioplasty. A higher risk of major bleeding complications is observed with abciximab in association with fibrinolysis.   相似文献   

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