PubMed Health⌕ Search

Biomedical subjects

Dave P Miller

Publications and source records attributed to Dave P Miller.

9 recordsLinked to original sources

Hospital delays in reperfusion for ST-elevation myocardial infarction: implications when selecting a reperfusion strategy.

BACKGROUND: It has been suggested that the survival benefit associated with primary percutaneous coronary intervention (PPCI) in ST-segment elevation myocardial infarction may be attenuated if door-to-balloon (DB) time is delayed by >1 hour beyond door-to-needle (DN) times for fibrinolytic therapy. Whereas DB times are rapid in randomized trials, they are often prolonged in routine practice. We hypothesized that in clinical practice, longer DB-DN times would be associated with higher mortality rates and reduced PPCI survival advantage. We also hypothesized that in addition to PPCI delays, patient risk factors would significantly modulate the relative survival advantage of PPCI over fibrinolysis. METHODS AND RESULTS: DB-DN times were calculated by subtracting median DN time from median DB time at a hospital using data from 192,509 patients at 645 National Registry of Myocardial Infarction hospitals. Hierarchical models that adjusted simultaneously for both patient-level risk factors and hospital-level covariates were used to evaluate the relationship between PCI-related delay, patient risk factors, and in-hospital mortality. Longer DB-DN times were associated with increased mortality (P<0.0001). The DB-DN time at which mortality rates with PPCI were no better than that of fibrinolysis varied considerably depending on patient age, symptom duration, and infarct location. CONCLUSIONS: As DB-DN times increase, the mortality advantage of PPCI over fibrinolysis declines, and this advantage varies considerably depending on patient characteristics. As indicated in the American College of Cardiology/American Heart Association guidelines, both the hospital-based PPCI-related delay (DB-DN time) and patient characteristics should be considered when a reperfusion strategy is selected.

Aged↗

Recent asthma exacerbations: a key predictor of future exacerbations.

OBJECTIVE: The objective of this analysis was to investigate whether patients with severe or difficult-to-treat asthma who experienced recent severe asthma exacerbations are at increased risk of future asthma exacerbations. METHODS: We conducted a 1.5-year prospective analysis of 2780 patients 12 > or =years of age from The Epidemiology and Natural History of Asthma: Outcomes and Treatment Regimens study. Severe exacerbations were defined as either an asthma-related emergency department visit or night of hospitalization in the 3 months prior to study visit; a secondary analysis assessed prior steroid bursts as an independent predictor and outcome. Potential confounding was assessed by statistical adjustment for demographic and clinical factors, as well as asthma severity and asthma control. RESULTS: Compared with patients without a recent severe exacerbation, patients with a recent exacerbation were at increased risk of future exacerbation (odds ratio=6.33; 95% CI 4.57, 8.76), even after adjustment for demographics and clinical factors (odds ratio=3.77; 95% CI 2.62, 5.43), asthma severity (physician-assessed: odds ratio=5.62; 95% CI 4.03, 7.83), National Asthma Education and Prevention Program (odds ratio=5.07; 95% CI 3.62, 7.11), Global Initiative for Asthma (odds ratio=5.32; 95% CI 3.80, 7.47), and asthma control (odds ratio=3.90; 95% CI 2.77, 5.50). CONCLUSION: This analysis suggests that recent severe asthma exacerbations are a strong independent factor predicting future exacerbations and, as such, should be considered as part of the clinical assessment of patients with severe or difficult-to-treat asthma.

Adolescent↗

Computer-aided detection of solid lung nodules in lossy compressed multidetector computed tomography chest exams.

RATIONALE AND OBJECTIVES: To assess the effect of three-dimensional (3D) lossy image compression of multidetector computed tomography chest scans on computer-aided detection (CAD) of solid lung nodules greater than 4 mm in size. MATERIALS AND METHODS: A total of 120 cases, acquired with 1.25-mm collimation, were collected from 5 different sites, of which 66/120 were low-dose cases. Two chest radiologists established that 37 cases had no actionable lung nodules; the remaining 83 cases contained 169 nodules (range 3.8-35.0 mm, mean 5.8 mm +/- 3.0 [SD]). All cases were compressed using the 3D Set Partitioning in Hierarchical Trees algorithm to 24:1, 48:1, and 96:1 levels. A study of the effect of compression on computer-aided detection (CAD) sensitivity was performed at operating points of 2.5 false marks (FM), 5 FM, and 10 FM per case using McNemar's test. Logistic regression models were used to evaluate the impact on CAD sensitivity by compression level on nodule and image characteristics. RESULTS: Compared with no compression, there was no significant degradation in CAD sensitivity found at any of the studied compression levels and operating points. However, between compression levels, there was marginal association with sensitivity. Specifically, 24:1 level was significantly better than 96:1 at all operating points, and occasionally better than no compression at 10 FM/case. Based on multivariate analysis, nodule location was found to be a significant predictor (P = .01) with a lower sensitivity associated with juxtapleural nodules. Nodule size, dose, reconstruction filter, and contrast medium were not significant predictors. CONCLUSION: CAD detection performance of solid lung nodules did not suffer until 48:1 compression.

Algorithms↗

Gender differences in IgE-mediated allergic asthma in the epidemiology and natural history of asthma: Outcomes and Treatment Regimens (TENOR) study.

BACKGROUND: The TENOR study consists of a large cohort of subjects with severe or difficult-to-treat asthma. The objective of this analysis was to evaluate demographic and clinical characteristics of subjects 12 years of age or older with immunoglobulin E (IgE)-mediated allergic asthma (skin test positive with an IgE level = 30 to =700 IU/mL), and specifically, to assess gender differences in this cohort. METHODS: A total of 4,756 subjects were enrolled by 283 US study sites between January and October 2001. Of those subjects 12 years or older at baseline with an IgE measure and who were skin tested (n = 2,843), 1,783 (63%) were skin test positive and had an IgE level between = 30 to = 700 IU/mL. RESULTS: Compared to males, females reported significantly greater healthcare utilization (steroid bursts in previous 3 months: 50% vs 42%, p < 0.001; unscheduled office visits in previous 3 months: 50% vs 36%, p < 0.0001; missed 1+ days of work/school in previous 2 weeks: 14% vs 10%, p < 0.01). Females also reported significantly more asthma control problems and lower asthma-related quality of life (4.6 +/- 1.3 vs 5.2 +/- 1.2; p < 0.0001); the difference was clinically meaningful. Asthma triggers and allergic comorbidities, such as allergic rhinitis and atopic dermatitis, were more common in female subjects. Despite their overall worse health outcomes, female subjects demonstrated better lung function, had similar treatment patterns, and showed no differences in physician-assessed asthma severity when compared with males. CONCLUSIONS: The reasons for these gender differences in subjects with IgE-mediated allergic asthma are complex, but results from this analysis suggest that detailed evaluations of asthma patients, including symptom-related questions and asthma-related healthcare utilization, are needed to accurately assess asthma severity and control.

Adolescent↗

High prevalence of skin test positivity in severe or difficult-to-treat asthma.

BACKGROUND: Skin tests are considered the gold standard for detecting allergen-specific immunoglobulin E (IgE) in the clinical setting and are an important tool for diagnosing and managing allergic asthma. OBJECTIVE: To assess the prevalence of skin testing in patients > or = 12 years enrolled in The Epidemiology and Natural History of Asthma: Outcomes and Treatment Regimens (TENOR) study. METHODS: Patients were asked whether they had ever been skin tested and, if so, they were asked to provide the test results. Clinical characteristics were used to compare positive (ST+), negative (ST-), and skin test not done (STND) patients. RESULTS: Of 2,985 patients eligible, 85.8% recalled being skin tested. Of those tested, 93.5% were positive (allergist 95.7%, pulmonologist 87.3%). A high proportion of Whites (93.5%) and non-Whites (94.0%) were ST+; however, more non-Whites had never been skin tested (21.7% vs. 12.3%, respectively; p < 0.0001). Total serum IgE was 104.6 IU/mL for ST+ patients, 87.1 IU/mL for STND patients, and 32.4 IU/mL for ST- patients. Age at asthma onset, duration of asthma, and the prevalence of atopic disorders and asthma triggers differentiated the ST+ from the ST- group. Disease severity appeared similar between the two groups. In general, values for STND patients were closer to the ST+ group, suggesting that those not tested would have been ST+ if administered a test. CONCLUSIONS: The prevalence of ST+ patients was high in allergy and pulmonology practices, and in White and non-White patients. These data support the utility of a more complete allergic evaluation in severe asthmatics. Skin testing appears associated with disease pathophysiologies in asthma.

Adult↗

Severity assessment in asthma: An evolving concept.

BACKGROUND: Guidelines for the clinical management of asthma base specific treatment recommendations on the assessment of disease severity. Thus, the accuracy of such assessments is essential for proper clinical management. The consistency of asthma severity assessment in patients with difficult-to-treat disease is unknown. OBJECTIVE: The objectives of this analysis were to compare the asthma severity assessment according to 3 methodologies in patients from The Epidemiology and Natural History of Asthma: Outcomes and Treatment Regimens study. METHODS: Asthma severity on the basis of the National Asthma Education and Prevention Program and the Global Initiative for Asthma guidelines was compared with physician assessment and benchmarked against asthma-related health care use. Guideline-based asthma severity symptom components were derived from patient-reported questionnaires. Lung function levels were determined by prebronchodilator FEV(1) measurements; asthma-related medication and recent health care use were reported by patients. RESULTS: There was a clear lack of agreement among the asthma severity assessment modalities. Asthma severity was associated with asthma-related health care use, and patients considered to have severe asthma according to both sets of guidelines and physicians' assessment had the highest health care and medication use. CONCLUSION: Classification of asthma severity on the basis of current asthma symptoms and lung function may be useful but not completely reflective of a patient's true asthma condition. Clinical assessment of asthma severity should consider a patient's medication use and consumption of health care resources for asthma exacerbations. Additional studies that apply criteria for asthma severity longitudinally are needed to support recommendations for optimal assessment of asthma severity.

Adolescent↗

Aspirin sensitivity and severity of asthma: evidence for irreversible airway obstruction in patients with severe or difficult-to-treat asthma.

BACKGROUND: Patients with aspirin sensitivity experience hyperplastic sinusitis and nasal polyposis. We speculated that similar mechanisms could be acting in the lower airway and that these individuals would demonstrate more severe asthma and irreversible loss of lung function. OBJECTIVE: We sought to investigate the role of aspirin-exacerbated respiratory disease (AERD) as a risk factor for the development of irreversible airway obstruction. METHODS: The Epidemiology and Natural History of Asthma: Outcomes and Treatment Regimens (TENOR) study is a multicenter observational study of subjects with severe or difficult-to-treat asthma. Data were compared between subjects who reported asthma exacerbation after aspirin ingestion and those who did not. The primary measure of bronchodilator-resistant obstruction (possible remodeling) was the maximally achieved postbronchodilator spirometry averaged over the 3-year duration of the study. RESULTS: Adult subjects (>/=18 years) with AERD (n = 459) were compared with subjects with non-aspirin-sensitive asthma (n = 2848). Subjects with AERD had significantly lower mean postbronchodilator percent predicted FEV(1) compared with subjects with non-aspirin-sensitive asthma (75.3% vs 79.9%, P < .001). Differences in spirometry between the 2 cohorts persisted after controlling for potential confounding variables. In addition, subjects with AERD were more likely to have severe asthma by means of physician assessment (66% vs 49%, P < .001), to have been intubated (20% vs 11%, P < .001), to have a steroid burst in the previous 3 months (56% vs 46%, P < .001), and to have required high-dose inhaled corticosteroids (34% vs 26%, P < .001). CONCLUSIONS: These data suggest that aspirin sensitivity is associated with increased asthma severity and possible remodeling of both the upper and lower airways.

Adolescent↗

Aircraft cabin air recirculation and symptoms of the common cold.

CONTEXT: In recent years, new commercial aircraft have been designed to recirculate approximately 50% of the cabin air to increase fuel efficiency. Some older aircraft use only fresh air. Whether air recirculation increases the transmission of infectious disease is unknown; some studies have demonstrated higher rates of the common cold among persons working in buildings that recirculate air. OBJECTIVE: To evaluate the role of air recirculation as a predictor of postflight upper respiratory tract infections (URIs). DESIGN, SETTING, AND PARTICIPANTS: A natural experiment conducted among 1100 passengers departing the San Francisco Bay area in California and traveling to Denver, Colo, during January through early April 1999, and who completed a questionnaire in the boarding area and a follow-up telephone interview 5 to 7 days later. Forty-seven percent traveled aboard airplanes using 100% fresh air for ventilation, and 53% traveled aboard aircraft that recirculated cabin air. MAIN OUTCOME MEASURE: Incidence of reporting new URI symptoms within 1 week of the flight. RESULTS: Passengers on airplanes that did and did not recirculate air had similar rates of postflight respiratory symptoms. The rates of reporting a cold were 19% vs 21% (P =.34); a runny nose and a cold, 10% vs 11%, (P =.70); and an aggregation of 8 URI symptoms, 3% in both groups (P>.99). Results were similar after statistical adjustment for potential confounders. CONCLUSION: We found no evidence that aircraft cabin air recirculation increases the risk for URI symptoms in passengers traveling aboard commercial jets.

Adult↗