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991.
New technologies and potential cost savings related to morbidity and mortality reduction in Class III/IV heart failure patients in Canada 总被引:2,自引:0,他引:2
Bentkover JD Stewart EJ Ignaszewski A Lepage S Liu P Cooper J 《International journal of cardiology》2003,88(1):33-41
BACKGROUND: Heart failure affects 1-2% of the Canadian population. The 1-year mortality rates in New York Heart Association Class III/IV heart failure patients range from 11 to 44%. This study evaluates costs associated with current management of Class III/IV heart failure and potential savings if morbidity and mortality are reduced. OBJECTIVES: To construct an economic model to evaluate the components of treating Class III/IV heart failure patients in Canada and the resulting direct medical costs. The model also estimates the potential savings that could result from the introduction of a new technology such as cardiac resynchronization therapy that reduces morbidity and mortality. METHODS: The model evaluates costs of pharmacological therapy, medical care, laboratory and diagnostic tests, and complications, most commonly hospitalization. Estimates are based on a literature review, expert opinion, and standard cost sources using widely accepted health economic methods. RESULTS: The model, under conservative assumptions, estimates that Class III/IV heart failure costs between CAD$1.4 billion and CAD$2.3 billion in Canada overall. Costs are substantial on the provincial level as well and are estimated to be approximately CAD$700 million, CAD$500 million, and CAD$300 million in Ontario, Québec, and British Columbia, respectively. New treatments could bring substantial savings depending on their effectiveness-measured as reduction in morbidity and mortality-and the number of patients who receive that treatment. Potential savings in Canada could reduce the total annual costs for this group of patients by approximately 10% or up to CAD$200 million annually. CONCLUSIONS: The high level of morbidity and mortality in Class III/IV heart failure patients and costs associated with their care are an impetus for the development of new therapies such as cardiac resynchronization therapy, that could deliver long-term benefits including increased exercise tolerance, reduced hospitalizations, and improved quality of life. Successful therapies could provide substantial savings and present a favorable economic profile in the treatment of heart failure. In order to ensure that appropriate technologies are commercialized and marketed, prospective evaluation of new therapies should include critical assessment of direct medical costs in addition to evaluating morbidity, quality of life and survival. 相似文献
992.
van Laborde S Dover JS Moore M Stewart B Arndt KA Alam M 《Journal of the American Academy of Dermatology》2003,48(6):875-877
BACKGROUND: Injection with botulinum A exotoxin reconstituted with preserved saline has been shown to be less uncomfortable than injection with the same toxin reconstituted with preservative-free saline. OBJECTIVE: We sought to determine whether injection with botulinum toxin type B is similarly less painful when preservative-containing saline is used to further dilute the product. METHODS: We conducted a double-blind, randomized controlled trial. A total of 15 consecutive adult patients presenting for treatment of upper face dynamic lines received treatment to one side (left or right) of the face with toxin type B further diluted with preservative-containing saline, and to the other side with toxin type B further diluted with preservative-free saline. RESULTS: Of 15 patients, 13 (87%) reported less pain in the halves of their faces treated with the preservative-containing saline (P =.0006). Pain on the preservative-containing side was on average 32% less among patients as a whole, and 39% less among patients noting some reduction. The 95% confidence interval for pain reduction associated with preservative-containing injection was -46.9% to -16.1%. Neither investigators nor patients observed any difference in clinical efficacy between the 2 treatment sides. CONCLUSIONS: Use of preservative-containing saline to further dilute botulinum toxin type B can significantly decrease patient discomfort on injection. 相似文献
993.
994.
The accuracy of dental panoramic tomographs in determining the root morphology of mandibular third molar teeth before surgery 总被引:4,自引:0,他引:4
Bell GW Rodgers JM Grime RJ Edwards KL Hahn MR Dorman ML Keen WD Stewart DJ Hampton N 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2003,95(1):119-125
OBJECTIVE: The objective of this study was to assess the accuracy of dental panoramic tomograph (DPT) in the presurgical assessment of mandibular third molar teeth by correlating the radiologic interpretation with surgical findings. STUDY DESIGN: DPTs of 300 mandibular third molar teeth were assessed by 9 staff oral surgeons for root morphology and proximity to the inferior alveolar neurovascular bundle. Detailed records were made at surgery. RESULTS: The sensitivity and specificity for observation of root curvatures (+/-15%) were 29% and 94%, respectively. The sensitivity and specificity of determining an intimate relationship between the root and the neurovascular bundle were 66% and 74%, respectively. Kappa analysis demonstrated poor levels of agreement between radiologic interpretation and surgical findings when the number of roots was determined (0.191) and also when the roots were fused or separate (0.466). CONCLUSION: Using DPTs to assess mandibular third molar teeth before surgery gives poor diagnostic accuracy of anatomic form and structures. 相似文献
995.
Sielski C Conforti N Stewart B Chaknis P Petrone ME DeVizio W Volpe AR Proskin HM 《Compendium of continuing education in dentistry (Jamesburg, N.J. : 1995)》2003,24(8):612-4, 616-8
The objective of this randomized, controlled, examiner-blind, parallel-group clinical study was to determine whether a tooth-whitening gel (Colgate Simply White Night Clear Whitening Gel) can significantly lighten teeth when used once daily at night, as compared with a commercially available dentifrice. Following a baseline tooth shade evaluation using the VITA Shade Guide, qualifying adult male and female subjects from the Buffalo, New York area were randomized into 2 treatment groups, which were balanced for baseline VITA Shade Guide scores, gender, and age. The treatment groups were: (1) a commercially available dentifrice only; and (2) a tooth-whitening gel in addition to a commercially available dentifrice. Subjects assigned to the 2 groups were given the dentifrice and a soft-bristled toothbrush. In addition, subjects in one of the groups were given the tooth-whitening gel. All subjects were instructed to brush their teeth for 1 minute twice daily (morning and evening) with the dentifrice. The subjects in the group also using the tooth-whitening gel were further instructed to apply the gel once daily at night, as per manufacturer instructions. Evaluations of tooth shade for each subject were repeated after 2 weeks, and again after 3 weeks of product use. In addition, evaluations of tooth shade for subjects using the tooth-whitening gel were later conducted at 6 months after product use. Seventy-five subjects complied with the protocol and completed the study. At the 2-week and 3-week examinations, subjects using the tooth-whitening gel and dentifrice exhibited statistically significant (P < .05) tooth shade lightening relative to baseline tooth shade. Furthermore, at the 2-week and 3-week examinations, subjects using the tooth-whitening gel exhibited statistically significant (P < .05) tooth shade lightening relative to subjects using only the dentifrice. In addition, the 6-month-postuse examination showed that subjects using the tooth-whitening gel exhibited statistically significant (P < .05) tooth shade lightening relative to baseline, thereby maintaining the tooth shade lightening that was evident at 3 weeks. The results of this clinical study indicate that after once-daily use at night for 2 or 3 weeks, the tooth-whitening gel provided statistically significant tooth shade lightening relative to baseline tooth shade for up to at least 6 months and also provided statistically significant tooth shade lightening relative to a commercially available dentifrice after 2 and 3 weeks of product use. 相似文献
996.
997.
Meta-analysis of the effects of endothelin receptor blockade on survival in experimental heart failure 总被引:1,自引:0,他引:1
Lee DS Nguyen QT Lapointe N Austin PC Ohlsson A Tu JV Stewart DJ Rouleau JL 《Journal of cardiac failure》2003,9(5):368-374
BACKGROUND: Although an initial study of endothelin receptor blockade reported positive findings, subsequent experiments and clinical trials in humans found little or no benefit. METHODS: We applied meta-analytic methods to assess the methodologic rigor of preclinical studies of endothelin blockade and to quantitatively evaluate the totality of evidence regarding the effect of endothelin receptor blockers in experimental heart failure. A total of 396 animals were assigned to control and 594 were assigned to experimental therapy in the pooled analysis. Of the 9 studies identified, no study reported a priori sample size justification. Although there was a tendency to increased mortality with early administration (relative risk 1.39, P=.15) and decreased mortality with late administration (relative risk 0.85, P=.6), in the overall analysis, there was no significant evidence of benefit or harm (relative risk 1.03, P=.9). Studies with a small sample size had estimated effects that tended to deviate further from the pooled estimate of all studies. CONCLUSIONS: Consideration of mortality effects in the totality of studies revealed no significant effect of endothelin antagonists in animal models of experimental heart failure. Given the potential for between-study variability, reliance on studies with small sample size may lead to unrealistic expectations when extrapolating preclinical experimental results to future research. 相似文献
998.
Alcohol use and cardiovascular disease preventive services 总被引:1,自引:0,他引:1
Stewart SH 《Journal of cardiovascular risk》2003,10(3):221-225
BACKGROUND: Moderate drinking is associated with decreased cardiovascular mortality. Biological effects may mediate this association, but differences in utilization of preventive services may be important. DESIGN AND METHODS: Cross-sectional analysis of adults participating in the Third National Health and Nutrition Examination Survey with data on alcohol use and prior use of services for the detection and treatment of hypertension and hypercholesterolaemia. Regression models were analysed to provide age-, sex- and race-adjusted risk estimates for outcomes related to these services for several patterns of alcohol use relative to regular light drinkers. RESULTS: Hypertension was more common in most alcohol use strata compared with regular light drinkers (adjusted prevalence ratios 1.22 for lifelong abstainers, 1.33 for nonlifelong abstainers, 1.35 for infrequent moderate drinkers, 2.01 for frequent moderate drinkers, 1.73 for infrequent heavy drinkers and 1.98 for regular heavy drinkers, P-values < 0.05). Having had blood pressure measured was similar in all drinking strata. The prevalence of hypercholesterolaemia was similar in drinking strata, but most drinking patterns were associated with lower use of services to detect high cholesterol (prevalence ratios 0.7 for lifelong abstainers, 0.8 for nonlifelong abstainers, infrequent moderate and regular moderate drinkers, 0.6 for infrequent heavy drinkers, and 0.7 for regular heavy drinkers, P-values < 0.05). CONCLUSIONS: The utilization of cardiovascular disease preventive services may contribute to the beneficial association of moderate drinking with cardiovascular mortality. Additional research is needed to estimate the influence of differences in health services utilization on the association of alcohol use with cardiovascular disease outcomes. 相似文献
999.
1000.
Melnick DM Maio RF Blow FC Hill EM Wang SC Pomerantz R Kane ML Graham-Bermann S Weber J Farber MS 《The Journal of trauma》2002,53(1):33-37
BACKGROUND: Despite the increasing recognition of the problem of domestic violence (DV), it has not been studied in surgical populations. METHODS: Eligible patients underwent screening for a recent history of DV and alcohol abuse (AA). Other demographic, health, and injury-related data were also collected. RESULTS: Of 127 subjects entered into the study, 18% screened positive for DV and 21% screened positive for AA. Of those screening positive for DV, 65% screened positive for AA compared with 12% of those screening negative for DV (p < 0.001.) Screening for DV was recommended by a vast majority of subjects, with only 6% of subjects responding that it was not appropriate. CONCLUSION: Both DV and AA have a high prevalence among female trauma patients admitted to trauma centers. Nearly all subjects recommended screening for DV. Screening for DV should be incorporated into the routine care of female trauma patients. 相似文献