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61.
OBJECTIVES: Clinicians are told to use the number needed to treat (NNT) to compare the benefits of therapeutic strategies, and researchers are asked to report results this way, generally without considering differences among the studies from which these were derived. METHODS: The crude NNT currently advocated is compared to the NNT standardized for a common outcome, follow-up time, study population and comparator. An NNT model for cardiovascular disease is described as an example that addresses differences among studies of secondary prevention of cardiovascular disease. Crude NNTs are compared to those obtained from the model. RESULTS: Follow-up in the 18 trials identified varied from 1.0 to 6.2 years; rates of cardiovascular events in the untreated subgroups ranged from 4.8% to 45.9%. The crude NNTs were more variable (9.1-163.7) than those obtained from the model (9.1-75.2). The effect of standardization was substantial in some cases, with proportional changes ranging from a 91% decrease to a 223% increase. CONCLUSION: Using an NNT model to account for differences in study design allows for more meaningful comparisons.  相似文献   
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Until recently, cardiorespiratory fitness (CRF) has been overlooked as a potential modifier of the inverse association between obesity and mortality (the so-called obesity paradox), observed in patients with known or suspected cardiovascular (CV) disease. Evidence from five observational cohort studies of 30,104 patients (87% male) with CV disease indicates that CRF significantly alters the obesity paradox. There is general agreement across studies that the obesity paradox persists among patients with low CRF, regardless of whether adiposity is assessed by body mass index, waist circumference, or percentage body fat. However, among patients with high CRF, risk of all-cause mortality is lowest for the overweight category in some, but not all, studies, suggesting that higher levels of fitness may modify the relationship between body fatness and survival in patients manifesting an obesity paradox. Further study is needed to better characterize the joint contribution of CRF and obesity on mortality in diverse populations.  相似文献   
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Mobile phone social networking applications such as GRINDR are potential tools for recruitment of men who have sex with men (MSM) for HIV prevention research. Demographics and sexual risk behaviors of men recruited through GRINDR and through traditional media were compared. GRINDR participants were younger (mean age 31 vs. 42, p?<?0.0001), more White identified (44 vs. 30?%, p?<?0.01), and had more sex partners in the previous 14 days (1.88 vs. 1.10, p?<?0.05) than other recruits. Email responses were less successful for enrollment than phone calls (5 vs. 50?%). This approach resulted in successful recruitment of younger and more educated, White identified MSM.  相似文献   
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BackgroundThe Heart Truth Professional Education Campaign was developed to facilitate education of health care providers in evidence-based strategies to prevent cardiovascular disease (CVD) in women.MethodsAs part of the 3-year campaign, lectures based on the American Heart Association's evidence-based guidelines for CVD prevention in women were presented by local speakers to healthcare providers and students in three high-risk states: Delaware, Ohio, and New York. Participants' responses to pretest and posttest questions about CVD in women are presented. We performed t-test and multivariable linear regression to assess the influence of provider characteristics on baseline knowledge and knowledge change after the lecture.ResultsBetween 2008 and 2011, 2,995 healthcare providers, students, and other participants completed the baseline assessment. Knowledge scores at baseline were highest for physicians, with obstetrician/gynecologists scoring lowest (63%) and cardiologists highest (76%). Nurses had intermediate total knowledge (56%) and students had the lowest total knowledge (49%) at baseline. Pre- and post-lecture assessments were completed by 1,893 (63%) of attendees. Scores were significantly higher after the educational lecture (p ≤ .001), with greater increase for those with lower baseline scores. Baseline knowledge of the use of statins, hormone therapy, and antioxidants, as well as approaches to smoking cessation and treatment of hypertension, differed by provider type.ConclusionTailoring of lectures for non-physician audiences may be beneficial given differences in baseline knowledge. More emphasis is needed on statin use for all providers and on smoking cessation and treatment of hypertension for nurses, students, and other healthcare professionals.  相似文献   
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Antiphospholipid syndrome is a hypercoagulable disease that can present foot and ankle surgeons with a unique challenge in treating patients who present with thrombosis and ischemia despite having normal pedal pulses. Appropriate perioperative management is imperative in these patients, because limb- and life-threatening complications can occur postoperatively, despite aggressive anticoagulation. We present the case of a 46-year-old male who underwent a transmetatarsal amputation and, despite aggressive therapy, developed a myriad of complications postoperatively. At 10 months postoperatively, the patient was doing well in an accommodative orthotic with minimal pain while receiving continued aggressive therapy and follow-up examinations by a number of specialists to treat his antiphospholipid syndrome.  相似文献   
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Medical devices have been targets of hacking for over a decade, and this cybersecurity issue has affected many types of medical devices. Lately, the potential for hacking of cardiac devices (pacemakers and defibrillators) claimed the attention of the media, patients, and health care providers. This is a burgeoning problem that our newly electronically connected world faces. In this paper from the Electrophysiology Section Council, we briefly discuss various aspects of this relatively new threat in light of recent incidents involving the potential for hacking of cardiac devices. We explore the possible risks for the patients and the effect of device reconfiguration in an attempt to thwart cybersecurity threats. We provide an outline of what can be done to improve cybersecurity from the standpoint of the manufacturer, government, professional societies, physician, and patient.  相似文献   
69.

Background context

It has been reported that newly developed osteoporotic vertebral compression fractures (OVCFs) occur at a relatively high frequency after treatment. While there are many reports on possible risk factors, these have not yet been clearly established.

Purpose

The purpose of this study was to investigate the risk factors for newly developed OVCFs after treatment by vertebroplasty (VP), kyphoplasty (KP), or conservative treatment.

Study design/setting

A retrospective comparative study.

Patient sample

One hundred thirty-two patients who had radiographic follow-up data for one year or longer among 356 patients who were diagnosed with OVCF and underwent VP, KP or conservative treatment between March 2007 and February 2016.

Outcome measures

All records were examined for age, sex, body mass index (BMI), rheumatoid arthritis and other medical comorbidities, osteoporosis medication, bone mineral density (BMD), history of vertebral and nonvertebral fractures, treatment methods used, level of fractures, and presence of multiple fracture sites.

Methods

Patients were divided into those who manifested new OVCF (Group A) and those who did not (Group B). For the risk factor analysis, student's t-tests and chi-square tests were used in univariate analysis. Multivariate logistic regression analysis was carried out on variables with a p<.1 in the univariate analysis.

Results

Newly developed OVCFs occurred in 46 of the 132 patients (34.8%). Newly developed OVCF increased significantly with factors such as average age (p=.047), low BMD T-score of the lumbar spine (p=.04) and of the femoral neck (p=.046), advanced age (>70 years) (p=.011), treatment by cement augmentation (p=.047) and low compliance with osteoporosis medication (p=.029). In multivariate regression analysis, BMD T-score of the lumbar spine (p=.009) and treatment by cement augmentation (p=.044) showed significant correlations with the occurrence of new OVCFs with a predictability of 71.4%.

Conclusion

Osteoporotic vertebral compression fracture patients with low BMD T-score of the lumbar spine and those who have been treated by cement augmentation have an increased risk of new OVCFs after treatment and, therefore, require especially careful observation and attention.  相似文献   
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