Duration of anticoagulation following venous thromboembolism: a meta-analysis

David Ost, MD; Josh Tepper, MD; Hanako Mihara, MD, MPH; Owen Lander, MD; Raphael Heinzer, MD; Alan Fein, MD

JAMA. 2005;294:706-715.

Context  Patients with venous thromboembolism (VTE) are susceptible to recurrent events, but whether prolonging anticoagulation is warranted in patients with VTE remains controversial.

Objective  To review the available evidence and quantify the risks and benefits of extending the duration of anticoagulation in patients with VTE.

Data Sources  PubMed, EMBase Pharmacology, the Cochrane database, clinical trial Web sites, and a hand search of reference lists.

Study Selection  Included studies were randomized controlled trials with results published from 1969 through 2004 and evaluating the duration of anticoagulation in patients with VTE that measured recurrent VTE. Excluded studies were those enrolling only pure populations of high-risk patients. Two independent reviewers assessed each article for inclusion and exclusion criteria, with adjudication by a third reviewer in cases of disagreement. Fifteen of 67 studies were included in the analysis.

Data Extraction  Two independent reviewers performed data extraction using a standardized form, with adjudication by the remainder of the investigators in cases of disagreement. Data regarding recurrent VTE, major bleeding, person-time at risk, and study quality were extracted.

Data Synthesis  If patients in the long-term therapy group remained receiving anticoagulation, the risk of recurrent VTE with long- vs short-term therapy was reduced (weighted incidence rate, 0.020 vs 0.126 events/person-year; rate difference, –0.106 [95% confidence interval {CI}, –0.145 to –0.067]; P<.001; pooled incidence rate ratio [IRR], 0.21 [95% CI, 0.14 to 0.31]; P<.001). If anticoagulation in the long-term therapy group was discontinued, the risk reduction was less pronounced (weighted incidence rate, 0.052 vs 0.072 events/person-year; rate difference, –0.020 [95% CI, –0.039 to –0.001]; P = .04; pooled IRR, 0.69 [95% CI, 0.53 to 0.91]; P = .009). The risk of major bleeding with long- vs short-term therapy was similar (weighted incidence rate, 0.011 vs 0.006 events/person-year; rate difference, 0.005 [95% CI, –0.002 to 0.011]; P = .14; pooled IRR, 1.80 [95% CI, 0.72 to 4.51]; P = .21).

Conclusions  Patients who receive extended anticoagulation are protected from recurrent VTE while receiving long-term therapy. The clinical benefit is maintained after anticoagulation is discontinued, but the magnitude of the benefit is less pronounced.

     

Burden, features, and outcome of neurological involvement in acute falciparum malaria in Kenyan children

Context  Plasmodium falciparum appears to have a particular propensity to involve the brain but the burden, risk factors, and full extent of neurological involvement have not been systematically described. Objectives  To determine the incidence and describe the clinical phenotypes and outcomes of neurological involvement in African children with acute falciparum malaria. Design, Setting, and Patients  A review of records of all children younger than 14 years admitted to a Kenyan district hospital with malaria from January 1992 through December 2004. Neurological involvement was defined as convulsive seizures, agitation, prostration, or impaired consciousness or coma. Main Outcome Measures  The incidence, pattern, and outcome of neurological involvement. Results  Of 58 239 children admitted, 19 560 (33.6%) had malaria as the primary clinical diagnosis. Neurological involvement was observed in 9313 children (47.6%) and manifested as seizures (6563/17 517 [37.5%]), agitation (316/11 193 [2.8%]), prostration (3223/15 643 [20.6%]), and impaired consciousness or coma (2129/16 080 [13.2%]). In children younger than 5 years, the mean annual incidence of admissions with malaria was 2694 per 100 000 persons and the incidence of malaria with neurological involvement was 1156 per 100 000 persons. However, readmissions may have led to a 10% overestimate in incidence. Children with neurological involvement were older (median, 26 [interquartile range {IQR}, 15-41] vs 21 [IQR, 10-40] months; P<.001), had a shorter duration of illness (median, 2 [IQR, 1-3] vs 3 [IQR, 2-3] days; P<.001), and a higher geometric mean parasite density (42.0 [95% confidence interval {CI}, 40.0-44.1] vs 30.4 [95% CI, 29.0-31.8] x 10³/µL; P<.001). Factors independently associated with neurological involvement included past history of seizures (adjusted odds ratio [AOR], 3.50; 95% CI, 2.78-4.42), fever lasting 2 days or less (AOR, 2.02; 95% CI, 1.64-2.49), delayed capillary refill time (AOR, 3.66; 95% CI, 2.40-5.56), metabolic acidosis (AOR, 1.55; 95% CI, 1.29-1.87), and hypoglycemia (AOR, 2.11; 95% CI, 1.31-3.37). Mortality was higher in patients with neurological involvement (4.4% [95% CI, 4.2%-5.1%] vs 1.3% [95% CI, 1.1%-1.5%]; P<.001). At discharge, 159 (2.2%) of 7281 patients had neurological deficits. Conclusions  Neurological involvement is common in children in Kenya with acute falciparum malaria, and is associated with metabolic derangements, impaired perfusion, parasitemia, and increased mortality and neurological sequelae. This study suggests that falciparum malaria exposes many African children to brain insults.      

Prophylactic Oral Amiodarone for the Prevention of Arrhythmias that Begin Early After Revascularization, Valve Replacement, or Repair: PAPABEAR: a randomized controlled trial

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      

Fracture prevention with vitamin D supplementation: a meta-analysis of randomized controlled trials

Context  The role and dose of oral vitamin D supplementation in nonvertebral fracture prevention have not been well established. Objective  To estimate the effectiveness of vitamin D supplementation in preventing hip and nonvertebral fractures in older persons. Data Sources  A systematic review of English and non-English articles using MEDLINE and the Cochrane Controlled Trials Register (1960-2005), and EMBASE (1991-2005). Additional studies were identified by contacting clinical experts and searching bibliographies and abstracts presented at the American Society for Bone and Mineral Research (1995-2004). Search terms included randomized controlled trial (RCT), controlled clinical trial, random allocation, double-blind method, cholecalciferol, ergocalciferol, 25-hydroxyvitamin D, fractures, humans, elderly, falls, and bone density. Study Selection  Only double-blind RCTs of oral vitamin D supplementation (cholecalciferol, ergocalciferol) with or without calcium supplementation vs calcium supplementation or placebo in older persons (60 years) that examined hip or nonvertebral fractures were included. Data Extraction  Independent extraction of articles by 2 authors using predefined data fields, including study quality indicators. Data Synthesis  All pooled analyses were based on random-effects models. Five RCTs for hip fracture (n = 9294) and 7 RCTs for nonvertebral fracture risk (n = 9820) met our inclusion criteria. All trials used cholecalciferol. Heterogeneity among studies for both hip and nonvertebral fracture prevention was observed, which disappeared after pooling RCTs with low-dose (400 IU/d) and higher-dose vitamin D (700-800 IU/d), separately. A vitamin D dose of 700 to 800 IU/d reduced the relative risk (RR) of hip fracture by 26% (3 RCTs with 5572 persons; pooled RR, 0.74; 95% confidence interval [CI], 0.61-0.88) and any nonvertebral fracture by 23% (5 RCTs with 6098 persons; pooled RR, 0.77; 95% CI, 0.68-0.87) vs calcium or placebo. No significant benefit was observed for RCTs with 400 IU/d vitamin D (2 RCTs with 3722 persons; pooled RR for hip fracture, 1.15; 95% CI, 0.88-1.50; and pooled RR for any nonvertebral fracture, 1.03; 95% CI, 0.86-1.24). Conclusions  Oral vitamin D supplementation between 700 to 800 IU/d appears to reduce the risk of hip and any nonvertebral fractures in ambulatory or institutionalized elderly persons. An oral vitamin D dose of 400 IU/d is not sufficient for fracture prevention.      

Medicine residents' understanding of the biostatistics and results in the medical literature

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.      

Walking and leisure-time activity and risk of hip fracture in postmenopausal women

Context  Physical activity can reduce the risk of hip fractures in older women, although the required type and duration of activity have not been determined. Walking is the most common activity among older adults, and evidence suggests that it can increase femoral bone density and reduce fracture risk. Objective  To assess the relationship of walking, leisure-time activity, and risk of hip fracture among postmenopausal women. Design, Setting, and Participants  Prospective analysis begun in 1986 with 12 years of follow-up in the Nurses' Health Study cohort of registered nurses within 11 US states. A total of 61 200 postmenopausal women (aged 40-77 years and 98% white) without diagnosis of cancer, heart disease, stroke, or osteoporosis at baseline. Main Outcome Measures  Incident hip fracture resulting from low or moderate trauma, analyzed by intensity and duration of leisure-time activity and by time spent walking, sitting, and standing, measured at baseline and updated throughout follow-up. Results  From 1986 to 1998, 415 incident hip fracture cases were identified. After controlling for age, body mass index, use of postmenopausal hormones, smoking, and dietary intakes in proportional hazards models, risk of hip fracture was lowered by 6% (95% confidence interval [CI], 4%-9%; P<.001) for each increase of 3 metabolic equivalent (MET)–hours per week of activity (equivalent to 1 h/wk of walking at an average pace). Active women with at least 24 MET-h/wk had a 55% lower risk of hip fracture (relative risk [RR], 0.45; 95% CI, 0.32-0.63) compared with sedentary women with less than 3 MET-h/wk. Even women with a lower risk of hip fracture due to higher body weight experienced a further reduction in risk with higher levels of activity. Risk of hip fracture decreased linearly with increasing level of activity among women not taking postmenopausal hormones (P<.001), but not among women taking hormones (P = .24). Among women who did no other exercise, walking for at least 4 h/wk was associated with a 41% lower risk of hip fracture (RR, 0.59; 95% CI, 0.37-0.94) compared with less than 1 h/wk. More time spent standing was also independently associated with lower risks. Conclusion  Moderate levels of activity, including walking, are associated with substantially lower risk of hip fracture in postmenopausal women.      

Effects of reviparin, a low-molecular-weight heparin, on mortality, reinfarction, and strokes in patients with acute myocardial infarction presenting with ST-segment elevation

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.      

Contemporary clinical profile and outcome of prosthetic valve endocarditis

Context  Prosthetic valve endocarditis (PVE) is associated with significant mortality and morbidity. The contemporary clinical profile and outcome of PVE are not well defined. Objectives  To describe the prevalence, clinical characteristics, and outcome of PVE, with attention to health care–associated infection, and to determine prognostic factors associated with in-hospital mortality. Design, Setting, and Participants  Prospective, observational cohort study conducted at 61 medical centers in 28 countries, including 556 patients with definite PVE as defined by Duke University diagnostic criteria who were enrolled in the International Collaboration on Endocarditis-Prospective Cohort Study from June 2000 to August 2005. Main Outcome Measure  In-hospital mortality. Results  Definite PVE was present in 556 (20.1%) of 2670 patients with infective endocarditis. Staphylococcus aureus was the most common causative organism (128 patients [23.0%]), followed by coagulase-negative staphylococci (94 patients [16.9%]). Health care–associated PVE was present in 203 (36.5%) of the overall cohort. Seventy-one percent of health care–associated PVE occurred within the first year of valve implantation, and the majority of cases were diagnosed after the early (60-day) period. Surgery was performed in 272 (48.9%) patients during the index hospitalization. In-hospital death occurred in 127 (22.8%) patients and was predicted by older age, health care–associated infection (62/203 [30.5%]; adjusted odds ratio [OR], 1.62; 95% confidence interval [CI], 1.08-2.44; P = .02), S aureus infection (44/128 [34.4%]; adjusted OR, 1.73; 95% CI, 1.01-2.95; P = .05), and complications of PVE, including heart failure (60/183 [32.8%]; adjusted OR, 2.33; 95% CI, 1.62-3.34; P<.001), stroke (34/101 [33.7%]; adjusted OR, 2.25; 95% CI, 1.25-4.03; P = .007), intracardiac abscess (47/144 [32.6%]; adjusted OR, 1.86; 95% CI, 1.10-3.15; P = .02), and persistent bacteremia (27/49 [55.1%]; adjusted OR, 4.29; 95% CI, 1.99-9.22; P<.001). Conclusions  Prosthetic valve endocarditis accounts for a high percentage of all cases of infective endocarditis in many regions of the world. Staphylococcus aureus is now the leading cause of PVE. Health care–associated infection significantly influences the clinical characteristics and outcome of PVE. Complications of PVE strongly predict in-hospital mortality, which remains high despite prompt diagnosis and the frequent use of surgical intervention.      

Efficacy of a hip protector to prevent hip fracture in nursing home residents: the HIP PRO randomized controlled trial

Context  Past studies of the efficacy of hip protectors to prevent hip fracture in nursing home residents have had conflicting results, possibly due to potential biases from clustered randomization designs and modest adherence to intervention. Objective  To determine whether an energy-absorbing and energy-dispersing hip protector would reduce the risk of hip fracture when worn by nursing home residents. Design, Setting, and Participants  Multicenter, randomized controlled clinical trial in which 37 nursing homes were randomly assigned to having residents wear a 1-sided hip protector on the left or right hip. Participants were 1042 nursing home residents (mean [SD] aged 85 [7] years; 79% women) who consented and adhered to the hip protector use during a 2-week run-in period and were enrolled. Participating facilities were in greater Boston, Massachusetts, St Louis, Missouri, and Baltimore, Maryland from October 2002 to October 2004. Mean duration of participation for nursing home residents was 7.8 months. None were withdrawn because of adverse effects. Intervention(s)  Undergarments with a 1-sided hip protector made of a 0.32-cm outer layer of polyethylene (2.7 kg/m³) backed by a hard high-density polyethylene shield (0.95 cm) that was backed by 0.9 kg/m³ of 1.27-kg ethylene vinyl acetate foam. Each facility was visited 3 times per week to assess adherence and provide staff support. Main Outcome Measure  Adjudicated hip fracture occurrences on padded vs unpadded hips. Results  After a 20-month follow-up (676 person-years of observation), the study was terminated due to a lack of efficacy. The incidence rate of hip fracture on protected vs unprotected hips did not differ (3.1%; 95% confidence interval [CI], 1.8%-4.4% vs 2.5%; 95% CI, 1.3%-3.7%; P = .70). For the 334 nursing home residents with greater than 80% adherence to hip protector use, the incidence rate of hip fracture on protected vs unprotected hips did not differ (5.3%; 95% CI, 2.6%-8.8% vs 3.5%; 95% CI, 1.3%-5.7%; P = .42). Overall adherence was 73.8%. Conclusions  In this clinical trial of an energy-absorbing/shunting hip protector conducted in US nursing homes, we were unable to detect a protective effect on the risk of hip fracture, despite good adherence to protocol. These results add to the increasing body of evidence that hip protectors, as currently designed, are not effective for preventing hip fracture among nursing home residents. Trial Registration  clinicaltrials.gov Identifier: NCT00058864      

Exposure to infant siblings during early life and risk of multiple sclerosis

Context  The "hygiene hypothesis" has implicated sibship as a marker of infection load during early life and suggests that exposure or reexposure to infections can influence the developing immune system. Viral infection has also been implicated in the pathogenesis of multiple sclerosis (MS). Objectives  To evaluate whether exposure to infant siblings in early life is associated with the risk of MS, and to explore the possible mechanism for any apparent protective effect, including altered Epstein-Barr virus (EBV) infection patterns. Design, Setting, and Patients  Population-based case-control study in Tasmania, Australia, from 1999 to 2001 based on 136 cases of magnetic resonance imaging–confirmed MS and 272 community controls, matched on sex and year of birth. Main Outcome Measure  Risk of MS by duration of contact with younger siblings aged less than 2 years in the first 6 years of life. Results  Increasing duration of contact with a younger sibling aged less than 2 years in the first 6 years of life was associated with reduced MS risk (adjusted odds ratios [AORs]: <1 infant-year, 1.00 [reference]; 1 to <3 infant-years, 0.57 [95% confidence interval {CI}, 0.33-0.98]; 3 to <5 infant-years, 0.40 [95% CI, 0.19-0.92]; 5 infant-years, 0.12 [95% CI, 0.02-0.88]; test for trend, P = .002). A history of exposure to infant siblings was associated with a reduced IgG response to EBV among controls. Controls with at least 1 infant-year contact had a reduced risk of infectious mononucleosis and a reduced risk of very high composite EBV IgG titers (AOR, 0.33; 95% CI, 0.11-0.98) compared with other controls. The inverse association between higher infant contact and MS was independent of EBV IgG titer. Conclusion  Higher infant sibling exposure in the first 6 years of life was associated with a reduced risk of MS, possibly by altering childhood infection patterns and related immune responses.      

Incidence of childhood distal forearm fractures over 30 years: a population-based study

Context  The incidence of distal forearm fractures in children peaks around the time of the pubertal growth spurt, possibly because physical activity increases at the time of a transient deficit in cortical bone mass due to the increased calcium demand during maximal skeletal growth. Changes in physical activity or diet may therefore influence risk of forearm fracture. Objective  To determine whether there has been a change in the incidence of distal forearm fractures in children in recent years. Design, Setting and Patients  Population-based study among Rochester, Minn, residents younger than 35 years with distal forearm fractures in 1969-1971, 1979-1981, 1989-1991, and 1999-2001. Main Outcome Measure  Estimated incidence of distal forearm fractures in 4 time periods. Results  Comparably age- and sex-adjusted annual incidence rates per 100 000 increased from 263.3 (95% confidence interval [CI], 231.1-295.4) in 1969-1971 to 322.3 (95% CI, 285.3-359.4) in 1979-1981 and to 399.8 (95% CI, 361.0-438.6) in 1989-1991 before leveling off at 372.9 (95% CI, 339.1-406.7) in 1999-2001. Age-adjusted incidence rates per 100 000 were 32% greater among male residents in 1999-2001 compared with 1969-1971 (409.4 [95% CI, 359.9-459.0] vs 309.4 [95% CI, 259.3-359.5]; P = .01) and 56% greater among female residents in the same time periods (334.3 [95% CI, 288.6-380.1] vs 214.6 [95% CI, 174.9-254.4]; P<.001). The peak incidence and greatest increase occurred between ages 11 and 14 years in boys and 8 and 11 years in girls. Conclusions  There has been a statistically significant increase in the incidence of distal forearm fractures in children and adolescents, but whether this is due to changing patterns of physical activity, decreased bone acquisition due to poor calcium intake, or both is unclear at present. Given the large number of childhood fractures, however, studies are needed to define the cause(s) of this increase.      

Effect of glucose-insulin-potassium infusion on mortality in patients with acute ST-segment elevation myocardial infarction: the CREATE-ECLA randomized controlled trial

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.      

Effects of estrogen plus progestin on risk of fracture and bone mineral density: the Women's Health Initiative randomized trial

Context  In the Women's Health Initiative trial of estrogen-plus-progestin therapy, women assigned to active treatment had fewer fractures. Objective  To test the hypothesis that the relative risk reduction of estrogen plus progestin on fractures differs according to risk factors for fractures. Design, Setting, and Participants  Randomized controlled trial (September 1993-July 2002) in which 16 608 postmenopausal women aged 50 to 79 years with an intact uterus at baseline were recruited at 40 US clinical centers and followed up for an average of 5.6 years. Intervention  Women were randomly assigned to receive conjugated equine estrogen, 0.625 mg/d, plus medroxyprogesterone acetate, 2.5 mg/d, in 1 tablet (n = 8506) or placebo (n = 8102). Main Outcome Measures  All confirmed osteoporotic fracture events that occurred from enrollment to discontinuation of the trial (July 7, 2002); bone mineral density (BMD), measured in a subset of women (n = 1024) at baseline and years 1 and 3; and a global index, developed to summarize the balance of risks and benefits to test whether the risk-benefit profile differed across tertiles of fracture risk. Results  Seven hundred thirty-three women (8.6%) in the estrogen-plus-progestin group and 896 women (11.1%) in the placebo group experienced a fracture (hazard ratio [HR], 0.76; 95% confidence interval [CI], 0.69-0.83). The effect did not differ in women stratified by age, body mass index, smoking status, history of falls, personal and family history of fracture, total calcium intake, past use of hormone therapy, BMD, or summary fracture risk score. Total hip BMD increased 3.7% after 3 years of treatment with estrogen plus progestin compared with 0.14% in the placebo group (P<.001). The HR for the global index was similar across tertiles of the fracture risk scale (lowest fracture risk tertile, HR, 1.20; 95% CI, 0.93-1.58; middle tertile, HR, 1.23; 95% CI, 1.04-1.46; highest tertile, HR, 1.03; 95% CI, 0.88-1.24) (P for interaction = .54). Conclusions  This study demonstrates that estrogen plus progestin increases BMD and reduces the risk of fracture in healthy postmenopausal women. The decreased risk of fracture attributed to estrogen plus progestin appeared to be present in all subgroups of women examined. When considering the effects of hormone therapy on other important disease outcomes in a global model, there was no net benefit, even in women considered to be at high risk of fracture.      

Vitamin A Intake and Hip Fractures Among Postmenopausal Women

Context  Ingestion of toxic amounts of vitamin A affects bone remodeling and can have adverse skeletal effects in animals. The possibility has been raised that long-term high vitamin A intake could contribute to fracture risk in humans. Objective  To assess the relationship between high vitamin A intake from foods and supplements and risk of hip fracture among postmenopausal women. Design  Prospective analysis begun in 1980 with 18 years of follow-up within the Nurses' Health Study. Setting  General community of registered nurses within 11 US states. Participants  A total of 72 337 postmenopausal women aged 34 to 77 years. Main Outcome Measures  Incident hip fractures resulting from low or moderate trauma, analyzed by quintiles of vitamin A intake and by use of multivitamins and vitamin A supplements, assessed at baseline and updated during follow-up. Results  From 1980 to 1998, 603 incident hip fractures resulting from low or moderate trauma were identified. After controlling for confounding factors, women in the highest quintile of total vitamin A intake (3000 µg/d of retinol equivalents [RE]) had a significantly elevated relative risk (RR) of hip fracture (RR, 1.48; 95% confidence interval [CI], 1.05-2.07; P for trend = .003) compared with women in the lowest quintile of intake (<1250 µg/d of RE). This increased risk was attributable primarily to retinol (RR, 1.89; 95% CI, 1.33-2.68; P for trend <.001 comparing 2000 µg/d vs <500 µg/d). The association of high retinol intake with hip fracture was attenuated among women using postmenopausal estrogens. Beta carotene did not contribute significantly to fracture risk (RR, 1.22; 95% CI, 0.90-1.66; P for trend = .10 comparing 6300 µg/d vs <2550 µg/d). Women currently taking a specific vitamin A supplement had a nonsignificant 40% increased risk of hip fracture (RR, 1.40; 95% CI, 0.99-1.99) compared with those not taking that supplement, and, among women not taking supplemental vitamin A, retinol from food was significantly associated with fracture risk (RR, 1.69; 95% CI, 1.05-2.74; P for trend = .05 comparing 1000 µg/d vs <400 µg/d). Conclusions  Long-term intake of a diet high in retinol may promote the development of osteoporotic hip fractures in women. The amounts of retinol in fortified foods and vitamin supplements may need to be reassessed.      

Differential genetic effects of ESR1 gene polymorphisms on osteoporosis outcomes

Context  Both bone mineral density (BMD) and fracture risk have a strong genetic component. Estrogen receptor (ESR1) is a candidate gene for osteoporosis, but previous studies of ESR1 polymorphisms in this field were hampered by small sample size, lack of standardization, and inconclusive results. Objective  To generate large-scale evidence on whether 3 common ESR1 polymorphisms (intron 1 polymorphisms XbaI [dbSNP: rs9340799] and PvuII [dbSNP: rs2234693] and promoter TA repeats microsatellite) and haplotypes thereof are associated with BMD and fractures. Design and Setting  Meta-analysis of individual-level data involving standardized genotyping of 18 917 individuals in 8 European centers. Main Outcome Measures  BMD of femoral neck and lumbar spine; all fractures and vertebral fractures by genotype. Results  No between-center heterogeneity was observed for any outcome in any genetic contrast. None of the 3 polymorphisms or haplotypes had any statistically significant effect on BMD in adjusted or unadjusted analyses, and estimated differences between genetic contrasts were 0.01 g/cm² or less. Conversely, we found significant reductions in fracture risk. In women homozygous for the absence of an XbaI recognition site, the adjusted odds of all fractures were reduced by 19% (odds ratio, 0.81 [95% CI, 0.71-0.93]; P = .002) and vertebral fractures by 35% (odds ratio, 0.65 [95% CI, 0.49-0.87]; P = .003). Effects on fractures were independent of BMD and unaltered in adjusted analyses. No significant effects on fracture risk were seen for PvuII and TA repeats. Conclusions  ESR1 is a susceptibility gene for fractures, and XbaI determines fracture risk by mechanisms independent of BMD. Our study demonstrates the value of adequately powered studies with standardized genotyping and clinical outcomes in defining effects of common genetic variants on complex diseases.      

Aspirin for the primary prevention of cardiovascular events in women and men: a sex-specific meta-analysis of randomized controlled trials

Context  Aspirin therapy reduces the risk of cardiovascular disease in adults who are at increased risk. However, it is unclear if women derive the same benefit as men. Objective  To determine if the benefits and risks of aspirin treatment in the primary prevention of cardiovascular disease vary by sex. Data Sources and Study Selection  MEDLINE and the Cochrane Central Register of Controlled Trials databases (1966 to March 2005), bibliographies of retrieved trials, and reports presented at major scientific meetings. Eligible studies were prospective, randomized controlled trials of aspirin therapy in participants without cardiovascular disease that reported data on myocardial infarction (MI), stroke, and cardiovascular mortality. Six trials with a total of 95 456 individuals were identified; 3 trials included only men, 1 included only women, and 2 included both sexes. Data Extraction  Studies were reviewed to determine the number of patients randomized, mean duration of follow-up, and end points (a composite of cardiovascular events [nonfatal MI, nonfatal stroke, and cardiovascular mortality], each of these individual components separately, and major bleeding). Data Synthesis  Among 51 342 women, there were 1285 major cardiovascular events: 625 strokes, 469 MIs, and 364 cardiovascular deaths. Aspirin therapy was associated with a significant 12% reduction in cardiovascular events (odds ratio [OR], 0.88; 95% confidence interval [CI], 0.79-0.99; P = .03) and a 17% reduction in stroke (OR, 0.83; 95% CI, 0.70-0.97; P = .02), which was a reflection of reduced rates of ischemic stroke (OR, 0.76; 95% CI, 0.63-0.93; P = .008). There was no significant effect on MI or cardiovascular mortality. Among 44 114 men, there were 2047 major cardiovascular events: 597 strokes, 1023 MIs, and 776 cardiovascular deaths. Aspirin therapy was associated with a significant 14% reduction in cardiovascular events (OR, 0.86; 95% CI, 0.78-0.94; P = .01) and a 32% reduction in MI (OR, 0.68; 95% CI, 0.54-0.86; P = .001). There was no significant effect on stroke or cardiovascular mortality. Aspirin treatment increased the risk of bleeding in women (OR, 1.68; 95% CI, 1.13-2.52; P = .01) and in men (OR, 1.72; 95% CI, 1.35-2.20; P<.001). Conclusions  For women and men, aspirin therapy reduced the risk of a composite of cardiovascular events due to its effect on reducing the risk of ischemic stroke in women and MI in men. Aspirin significantly increased the risk of bleeding to a similar degree among women and men.      

Outcomes and complications associated with off-label and untested use of drug-eluting stents

Context  Limited data exist regarding use of drug-eluting stents outside of approved indications in real-world settings. Objectives  To determine the frequency, safety, and effectiveness of drug-eluting stents for off-label (restenosis, bypass graft lesion, long lesions, vessel size outside of information for use recommendation) and untested (left main, ostial, bifurcation, or total occlusion lesions) indications in percutaneous coronary intervention (PCI). Design, Setting, and Patients  Observational, prospective, multicenter registry to evaluate in-hospital, 30-day, and 1-year outcomes among patients undergoing PCI between January and June 2005 in 140 US academic and community medical centers. Of 7752 PCI-treated patients, 6993 (90%) received drug-eluting stents; of these, 5851 (84%) received no other devices. Standard, off-label, and untested use was determined in 5541 (95%) of these 5851 patients, constituting the study cohort. Main Outcome Measures  Frequency of off-label and untested use, 1-year repeat target vessel revascularization, and composite of death, myocardial infarction (MI), or stent thrombosis at in-hospital follow-up and during 1 year of follow-up. Results  Of 5541 patients receiving drug-eluting stents, 2588 (47%) received stents for off-label or untested indications. Adjusted in-hospital risk of death, MI, or stent thrombosis was not statistically different with off-label or untested vs standard use. At 30 days, the risk of this composite end point was significantly higher with off-label use (adjusted hazard ratio [HR], 2.08; 95% confidence interval [CI], 1.24-3.48; P = .005) but not untested use (adjusted HR, 1.45; 95% CI, 0.79-2.67; P = .23). Excluding early events, this end point was not different at 1 year with off-label use (adjusted HR, 1.10; 95% CI, 0.79-1.54; P = .57) or untested use (adjusted HR, 0.91; 95% CI, 0.60-1.38; P = .66). At 1 year, compared with standard use, significantly higher rates of target vessel revascularization were associated with off-label use (adjusted HR, 1.49; 95% CI, 1.13-1.98; P = .005) and untested use (adjusted HR, 1.49; 95% CI, 1.10-2.02; P = .01), although absolute rates were low (standard, 4.4% [n = 113]; off-label, 7.6% [n = 95]; untested, 6.7% [n = 72]). Conclusions  In contemporary US practice, off-label and untested use of drug-eluting stents is common. Compared with standard use, relative early safety is lower with off-label use, and the long-term effectiveness is lower with both off-label and untested use. However, the absolute event rates remain low.      

Certificate of need regulations and use of coronary revascularization after acute myocardial infarction

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.      

Sirolimus-eluting stents vs vascular brachytherapy for in-stent restenosis within bare-metal stents: the SISR randomized trial

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