Diagnostic pathways in acute pulmonary embolism: recommendations of the PIOPED II Investigators.
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Acute Disease↗
Biomedical subjects
Sarah E Fowler
Publications and source records attributed to Sarah E Fowler.
Multidetector computed tomography for acute pulmonary embolism.
BACKGROUND: The accuracy of multidetector computed tomographic angiography (CTA) for the diagnosis of acute pulmonary embolism has not been determined conclusively. METHODS: The Prospective Investigation of Pulmonary Embolism Diagnosis II trial was a prospective, multicenter investigation of the accuracy of multidetector CTA alone and combined with venous-phase imaging (CTA-CTV) for the diagnosis of acute pulmonary embolism. We used a composite reference test to confirm or rule out the diagnosis of pulmonary embolism. RESULTS: Among 824 patients with a reference diagnosis and a completed CT study, CTA was inconclusive in 51 because of poor image quality. Excluding such inconclusive studies, the sensitivity of CTA was 83 percent and the specificity was 96 percent. Positive predictive values were 96 percent with a concordantly high or low probability on clinical assessment, 92 percent with an intermediate probability on clinical assessment, and nondiagnostic if clinical probability was discordant. CTA-CTV was inconclusive in 87 of 824 patients because the image quality of either CTA or CTV was poor. The sensitivity of CTA-CTV for pulmonary embolism was 90 percent, and specificity was 95 percent. CTA-CTV was also nondiagnostic with a discordant clinical probability. CONCLUSIONS: In patients with suspected pulmonary embolism, multidetector CTA-CTV has a higher diagnostic sensitivity than does CTA alone, with similar specificity. The predictive value of either CTA or CTA-CTV is high with a concordant clinical assessment, but additional testing is necessary when the clinical probability is inconsistent with the imaging results.
Acute Disease↗
Obesity and cardiovascular events in patients with established coronary disease.
AIMS: To explore the association between obesity and major adverse coronary events (MACE) in patients with established coronary artery disease (CAD). METHODS AND RESULTS: The Prevention of Events with Angiotensin Converting Enzyme-Inhibition (PEACE) Trial randomized 8290 patients with stable CAD and left ventricular (LV) ejection fraction (EF) (LVEF) > or =0.40 to trandolapril or placebo and followed them for a median of 4.8 years. In PEACE patients who were non-diabetic at baseline (5693 men and 1171 women), we used proportional hazards models to conduct a post hoc analysis to examine whether obesity, defined as a body mass index (BMI) > or =30 kg/m(2), is an independent risk factor for the composite endpoint of MACE, defined as cardiovascular death, non-fatal myocardial infarction, coronary revascularization, or stroke. The analysis was conducted separately for men and women. The baseline prevalence of obesity was 28.5% in men and 28.9% in women. After adjusting for significant confounders, obesity was associated with MACE in men [hazard ratio (HR) = 1.28, 95% CI 1.13-1.46, P < 0.01], but not in women (HR = 0.96, 95% CI 0.70-1.31, P = 0.77). Further categorization of BMI showed a J-shaped association between BMI and MACE in the men, and no association in the women. CONCLUSION: In the presence of established CAD, obesity is associated with risk for MACE in men, but there is no support of an association in women. This finding requires further evaluation.
Body Mass Index↗
Diagnostic pathways in acute pulmonary embolism: recommendations of the PIOPED II investigators.
PURPOSE: To formulate comprehensive recommendations for the diagnostic approach to patients with suspected pulmonary embolism, based on randomized trials. METHODS: Diagnostic management recommendations were formulated based on results of the Prospective Investigation of Pulmonary Embolism Diagnosis II (PIOPED II) and outcome studies. RESULTS: The PIOPED II investigators recommend stratification of all patients with suspected pulmonary embolism according to an objective clinical probability assessment. D-dimer should be measured by the quantitative rapid enzyme-linked immunosorbent assay (ELISA), and the combination of a negative D-dimer with a low or moderate clinical probability can safely exclude pulmonary embolism in many patients. If pulmonary embolism is not excluded, contrast-enhanced computed tomographic pulmonary angiography (CT angiography) in combination with venous phase imaging (CT venography), is recommended by most PIOPED II investigators, although CT angiography plus clinical assessment is an option. In pregnant women, ventilation/perfusion scans are recommended by many as the first imaging test following D-dimer and perhaps venous ultrasound. In patients with discordant findings of clinical assessment and CT angiograms or CT angiogram/CT venogram, further evaluation may be necessary. CONCLUSION: The sequence for diagnostic test in patients with suspected pulmonary embolism depends on the clinical circumstances.
Acute Disease↗
Prevention of type 2 diabetes with troglitazone in the Diabetes Prevention Program.
The Diabetes Prevention Program (DPP) was a randomized clinical trial of prevention of type 2 diabetes in high-risk people. Troglitazone, an insulin-sensitizing agent, was used initially but was discontinued during the trial. Troglitazone therapy was compared with other DPP interventions, considering both the short-term "in-trial" results and the longer-term results after troglitazone were discontinued. From 1996 to 1998, participants were randomly assigned to treatment with metformin (n = 587), troglitazone (n = 585), double placebo (n = 582), or intensive lifestyle intervention (ILS) (n = 589). Because of concern regarding its liver toxicity, the troglitazone arm was discontinued in June 1998, after which follow-up of all participants continued. During the mean 0.9 year (range 0.5-1.5 years) of troglitazone treatment, the diabetes incidence rate was 3.0 cases/100 person-years, compared with 12.0, 6.7, and 5.1 cases/100 person-years in the placebo, metformin, and ILS participants (P < 0.001, troglitazone vs. placebo; P = 0.02, troglitazone vs. metformin; P = 0.18, troglitazone vs. ILS). This effect of troglitazone was in part due to improved insulin sensitivity with maintenance of insulin secretion. During the 3 years after troglitazone withdrawal, the diabetes incidence rate was almost identical to that of the placebo group. Troglitazone, therefore, markedly reduced the incidence of diabetes during its limited period of use, but this action did not persist. Whether other thiazolidinedione drugs used for longer periods can safely prevent diabetes remains to be determined.
Chromans↗
Role of insulin secretion and sensitivity in the evolution of type 2 diabetes in the diabetes prevention program: effects of lifestyle intervention and metformin.
Insulin resistance and beta-cell dysfunction, two factors central to the pathogenesis of type 2 diabetes, were studied in relation to the development of diabetes in a group of participants with impaired glucose tolerance in the Diabetes Prevention Program (DPP) at baseline and after specific interventions designed to prevent diabetes. Participants were randomly assigned to placebo (n = 1,082), metformin (850 mg twice a day) (n = 1,073), or intensive lifestyle intervention (n = 1,079). The diabetes hazard rate was negatively associated with baseline insulin sensitivity (hazard rate ratio = 0.62-0.94 per SD difference, depending on treatment group and measure of sensitivity) and with baseline insulin secretion (hazard rate ratio = 0.57-0.76 per SD). Improvements in insulin secretion and insulin sensitivity were associated with lower hazard rates in all treatment arms (hazard rate ratio = 0.46-0.95 per SD increase and 0.29-0.79 per SD increase, respectively). In multivariate models that included the three metabolic variables (changes in body weight, insulin sensitivity, and insulin secretion) each significantly and independently predicted progression to diabetes when adjusted for the other two variables. The intensive lifestyle intervention, which elicited the greatest reduction in diabetes incidence, produced the greatest improvement in insulin sensitivity and the best preservation of beta-cell function after 1 year, whereas the placebo group, which had the highest diabetes incidence, had no significant change in insulin sensitivity and beta-cell function after 1 year. In the metformin group, diabetes risk, insulin sensitivity, and beta-cell function at 1 year were intermediate between those in the intensive lifestyle and placebo groups. In conclusion, higher insulin secretion and sensitivity at baseline and improvements in response to treatment were associated with lower diabetes risk in the DPP. The better preventive effectiveness of intensive lifestyle may be due to improved insulin sensitivity concomitant with preservation of beta-cell function.
Adult↗
Angiotensin-converting-enzyme inhibition in stable coronary artery disease.
BACKGROUND: Angiotensin-converting-enzyme (ACE) inhibitors are effective in reducing the risk of heart failure, myocardial infarction, and death from cardiovascular causes in patients with left ventricular systolic dysfunction or heart failure. ACE inhibitors have also been shown to reduce atherosclerotic complications in patients who have vascular disease without heart failure. METHODS: In the Prevention of Events with Angiotensin Converting Enzyme Inhibition (PEACE) Trial, we tested the hypothesis that patients with stable coronary artery disease and normal or slightly reduced left ventricular function derive therapeutic benefit from the addition of ACE inhibitors to modern conventional therapy. The trial was a double-blind, placebo-controlled study in which 8290 patients were randomly assigned to receive either trandolapril at a target dose of 4 mg per day (4158 patients) or matching placebo (4132 patients). RESULTS: The mean (+/-SD) age of the patients was 64+/-8 years, the mean blood pressure 133+/-17/78+/-10 mm Hg, and the mean left ventricular ejection fraction 58+/-9 percent. The patients received intensive treatment, with 72 percent having previously undergone coronary revascularization and 70 percent receiving lipid-lowering drugs. The incidence of the primary end point--death from cardiovascular causes, myocardial infarction, or coronary revascularization--was 21.9 percent in the trandolapril group, as compared with 22.5 percent in the placebo group (hazard ratio in the trandolapril group, 0.96; 95 percent confidence interval, 0.88 to 1.06; P=0.43) over a median follow-up period of 4.8 years. CONCLUSIONS: In patients with stable coronary heart disease and preserved left ventricular function who are receiving "current standard" therapy and in whom the rate of cardiovascular events is lower than in previous trials of ACE inhibitors in patients with vascular disease, there is no evidence that the addition of an ACE inhibitor provides further benefit in terms of death from cardiovascular causes, myocardial infarction, or coronary revascularization.
Aged↗
Gadolinium-enhanced magnetic resonance angiography for detection of acute pulmonary embolism: an in-depth review.
STUDY OBJECTIVE: To review the published experience with gadolinium-enhanced magnetic resonance angiography (MRA) for the detection of acute pulmonary embolism (PE) in order to test the hypothesis that gadolinium-enhanced MRA may be potentially sensitive and specific enough to include it among diagnostic alternatives in the evaluation of patients with suspected PE. METHODS: Studies were identified by searching MEDLINE for trials that used gadolinium-enhanced MRA to diagnose acute PE based on the visualization of an intraluminal filling defect or a cutoff vessel, using pulmonary angiography as a reference standard. RESULTS: Twenty-eight investigations were identified in which MRA was used to diagnose PE. Only three studies, however, met the criteria for inclusion in the analysis. In these three case series, the sensitivity of gadolinium-enhanced MRA ranged from 77 to 100%, and the specificity ranged from 95 to 98%. CONCLUSION: Gadolinium-enhanced MRA may be a useful diagnostic alternative in some patients with suspected acute PE, particularly if they have an elevated creatinine level, have an allergy to radiographic contrast material, or should, if possible, avoid exposure to ionizing radiation.
Acute Disease↗
Reduction in the incidence of type 2 diabetes with lifestyle intervention or metformin.
BACKGROUND: Type 2 diabetes affects approximately 8 percent of adults in the United States. Some risk factors--elevated plasma glucose concentrations in the fasting state and after an oral glucose load, overweight, and a sedentary lifestyle--are potentially reversible. We hypothesized that modifying these factors with a lifestyle-intervention program or the administration of metformin would prevent or delay the development of diabetes. METHODS: We randomly assigned 3234 nondiabetic persons with elevated fasting and post-load plasma glucose concentrations to placebo, metformin (850 mg twice daily), or a lifestyle-modification program with the goals of at least a 7 percent weight loss and at least 150 minutes of physical activity per week. The mean age of the participants was 51 years, and the mean body-mass index (the weight in kilograms divided by the square of the height in meters) was 34.0; 68 percent were women, and 45 percent were members of minority groups. RESULTS: The average follow-up was 2.8 years. The incidence of diabetes was 11.0, 7.8, and 4.8 cases per 100 person-years in the placebo, metformin, and lifestyle groups, respectively. The lifestyle intervention reduced the incidence by 58 percent (95 percent confidence interval, 48 to 66 percent) and metformin by 31 percent (95 percent confidence interval, 17 to 43 percent), as compared with placebo; the lifestyle intervention was significantly more effective than metformin. To prevent one case of diabetes during a period of three years, 6.9 persons would have to participate in the lifestyle-intervention program, and 13.9 would have to receive metformin. CONCLUSIONS: Lifestyle changes and treatment with metformin both reduced the incidence of diabetes in persons at high risk. The lifestyle intervention was more effective than metformin.
Adult↗