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1.
Transfus Med ; 29 Suppl 1: 42-51, 2019 Apr.
Article in English | MEDLINE | ID: mdl-29767450

ABSTRACT

OBJECTIVES: To evaluate the cost-effectiveness of changing opening times, introducing a donor health report and reducing the minimum inter-donation interval for donors attending static centres. BACKGROUND: Evidence is required about the effect of changes to the blood collection service on costs and the frequency of donation. METHODS/MATERIALS: This study estimated the effect of changes to the blood collection service in England on the annual number of whole-blood donations by current donors. We used donors' responses to a stated preference survey, donor registry data on donation frequency and deferral rates from the INTERVAL trial. Costs measured were those anticipated to differ between strategies. We reported the cost per additional unit of blood collected for each strategy versus current practice. Strategies with a cost per additional unit of whole blood less than £30 (an estimate of the current cost of collection) were judged likely to be cost-effective. RESULTS: In static donor centres, extending opening times to evenings and weekends provided an additional unit of whole blood at a cost of £23 and £29, respectively. Introducing a health report cost £130 per additional unit of blood collected. Although the strategy of reducing the minimum inter-donation interval had the lowest cost per additional unit of blood collected (£10), this increased the rate of deferrals due to low haemoglobin (Hb). CONCLUSION: The introduction of a donor health report is unlikely to provide a sufficient increase in donation frequency to justify the additional costs. A more cost-effective change is to extend opening hours for blood collection at static centres.


Subject(s)
Blood Donors , Donor Selection/economics , Adolescent , Adult , Cost-Benefit Analysis , England , Female , Humans , Male , Middle Aged
2.
BJOG ; 115(5): 653-62, 2008 Apr.
Article in English | MEDLINE | ID: mdl-18333948

ABSTRACT

OBJECTIVE: To estimate the cost-effectiveness of a treatment strategy for symptomatic uterine fibroids, which starts with Magnetic Resonance-guided Focused Ultrasound Surgery (MRgFUS) as compared with current practice comprising uterine artery embolisation, myomectomy and hysterectomy. DESIGN: Cost-utility analysis based on a Markov model. SETTING: National Health Service (NHS) Trusts in England and Wales. POPULATION: Women for whom surgical treatment for uterine fibroids is being considered. METHODS: The parameters of the Markov model of the treatment of uterine fibroids are drawn from a series of clinical studies of MRgFUS, and from the clinical effectiveness literature. Health-related quality of life is measured using the 6D. Costs are estimated from the perspective of the NHS. The impact of uncertainty is examined using deterministic and probabilistic sensitivity analysis. MAIN OUTCOME MEASURES: Incremental cost-effectiveness measured by cost per quality-adjusted life-year (QALY) gained. RESULTS: The base-case results imply a cost saving and a small QALY gain per woman as a result of an MRgFUS treatment strategy. The cost per QALY gained is sensitive to cost of MRgFUS relative to other treatments, the age of the woman and the nonperfused volume relative to the total fibroids volume. CONCLUSIONS: A treatment strategy for symptomatic uterine fibroids starting with MRgFUS is likely to be cost-effective.


Subject(s)
Leiomyoma/therapy , Magnetic Resonance Imaging, Interventional/economics , Ultrasonic Therapy/economics , Uterine Neoplasms/therapy , Adult , Cost-Benefit Analysis , Embolization, Therapeutic/economics , Embolization, Therapeutic/methods , Female , Humans , Hysterectomy/economics , Hysterectomy/methods , Leiomyoma/economics , Markov Chains , Middle Aged , Quality-Adjusted Life Years , Uterine Neoplasms/economics
3.
J Clin Invest ; 99(6): 1313-21, 1997 Mar 15.
Article in English | MEDLINE | ID: mdl-9077541

ABSTRACT

Mast cell activation is a characteristic feature of chronic inflammation, a condition that may lead to fibrosis as a result of increased collagen synthesis by fibroblasts. We have investigated the potential of tryptase, the major protease of human mast cells, to stimulate collagen synthesis in the human lung fibroblast cell line MRC-5. Tryptase was isolated from human lung tissue by ion-exchange and affinity chromatography. At concentrations of 18 and 36 mU/ml, tryptase stimulated both an increase in cell numbers, and a fivefold increase in DNA synthesis as determined by methyl-[3H]thymidine incorporation. Similar concentrations of tryptase resulted in a 2.5-fold increase in collagen synthesis as determined both by incorporation of [3H]proline into collagen, and by assay of hydroxyproline concentrations in the supernatants. There was also a twofold increase in collagenolytic activity in the culture medium after tryptase treatment, indicating that the increase in collagen synthesis was not a consequence of decreased collagenase production. All of these actions of tryptase were reduced in the presence of the protease inhibitors leupeptin and benzamidine hydrochloride, indicating a requirement for an active catalytic site. SDS-PAGE and autoradiographic analysis of the [3H]collagen produced by the cells revealed it to be predominantly type I collagen. Our findings suggest that the release of tryptase from activated mast cells may provide a signal for abnormal fibrosis in inflammatory disease.


Subject(s)
Collagen/biosynthesis , Fibroblasts/metabolism , Lung/metabolism , Mast Cells/enzymology , Serine Endopeptidases/pharmacology , Cell Division/drug effects , Cell Line , Chromatography, Ion Exchange , Chymases , Collagen/isolation & purification , Collagen/metabolism , Fibroblasts/cytology , Fibroblasts/enzymology , Humans , Hydroxyproline/metabolism , Lung/cytology , Lung/enzymology , Proline/metabolism , Time Factors , Tritium , Tryptases
4.
Eur J Cancer ; 43(17): 2506-14, 2007 Nov.
Article in English | MEDLINE | ID: mdl-17962011

ABSTRACT

AIM: The TELEMAM trial aimed to assess the clinical effectiveness and costs of telemedicine in conducting breast cancer multi-disciplinary meetings (MDTs). METHODS: Over 12 months 473 MDT patient discussions in two district general hospitals (DGHs) were cluster randomised (2:1) to the intervention of telemedicine linkage to breast specialists in a cancer centre or to the control group of 'in-person' meetings. Primary endpoints were clinical effectiveness and costs. Economic analysis was based on a cost-minimisation approach. RESULTS: Levels of agreement of MDT members on a scale from 1 to 5 were high and similar in both the telemedicine and standard meetings for decision sharing (4.04 versus 4.17), consensus (4.06 versus 4.20) and confidence in the decision (4.16 versus 4.07). The threshold at which the telemedicine meetings became cheaper than standard MDTs was approximately 40 meetings per year. CONCLUSION: Telemedicine delivered breast cancer multi-disciplinary meetings have similar clinical effectiveness to standard 'in-person' meetings.


Subject(s)
Breast Neoplasms/therapy , Decision Making , Telemedicine/statistics & numerical data , Attitude of Health Personnel , Breast Neoplasms/economics , Consumer Behavior , Costs and Cost Analysis , Female , Hospitals, District , Humans , Patient Care Team , Rural Health , Scotland , Telemedicine/economics , Treatment Outcome
5.
Can J Cardiol ; 23(2): 125-31, 2007 Feb.
Article in English | MEDLINE | ID: mdl-17311118

ABSTRACT

There is strong evidence from randomized clinical trials that the highly selective cox-2 inhibitors (coxibs), compared with placebo, cause an excess of serious cardiovascular events that are not mitigated by low-dose acetylsalicylic acid. Both Health Canada and the Food and Drug Administration have concluded that the excess cardiovascular events may be a 'class effect' of all the nonsteroidal anti-inflammatory drugs (NSAIDs), including traditional NSAIDs (tNSAIDs) and coxibs, and now require appropriate black box labelling of all these agents. Celecoxib and lumiracoxib are the only coxibs remaining on the market in Canada. The prostanoid pathways, the roles of cox-1 and cox-2, as well as the inhibitory effects of acetylsalicylic acid, traditional tNSAIDs and the coxibs, are briefly reviewed. Current recommendations for the ongoing use of coxibs and the tNSAIDs are summarized.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Aspirin/pharmacology , Cardiovascular Diseases/chemically induced , Cyclooxygenase 2 Inhibitors/pharmacology , Humans
6.
Circulation ; 99(17): 2268-75, 1999 May 04.
Article in English | MEDLINE | ID: mdl-10226092

ABSTRACT

BACKGROUND: Investigations with in vitro and animal models suggest an interaction between amiodarone and beta-blockers. The objective of this work was to explore if an interaction with beta-blocker treatment plays a role in the decrease of cardiac arrhythmic deaths with amiodarone in patients recovered from an acute myocardial infarction. METHODS AND RESULTS: A pooled database from 2 similar randomized clinical trials, the European Amiodarone Myocardial Infarction Trial (EMIAT) and the Canadian Amiodarone Myocardial Infarction Trial (CAMIAT), was used. Four groups of post-myocardial infarction patients were defined: beta-blockers and amiodarone used, beta-blockers used alone, amiodarone used alone, and neither used. All analyses were done on an intention-to-treat basis. Unadjusted and adjusted relative risks for all-cause mortality, cardiac death, arrhythmic cardiac death, nonarrhythmic cardiac death, arrhythmic death, or resuscitated cardiac arrest were lower for patients receiving beta-blockers and amiodarone than for those without beta-blockers, with or without amiodarone. The interaction was statistically significant for cardiac death and arrhythmic death or resuscitated cardiac arrest (P=0.05 and 0.03, respectively). Findings were consistent across subgroups. CONCLUSIONS: These findings are based on a post hoc analysis. However, they confirm prior results from in vitro and animal experiments suggesting an interaction between beta-blockers and amiodarone. In practice, not only is the adjunct of amiodarone to beta-blockers not hazardous, but beta-blocker therapy should be continued if possible in patients in whom amiodarone is indicated.


Subject(s)
Adrenergic beta-Antagonists/therapeutic use , Amiodarone/therapeutic use , Anti-Arrhythmia Agents/therapeutic use , Myocardial Infarction/drug therapy , Adrenergic beta-Antagonists/administration & dosage , Adult , Aged , Amiodarone/administration & dosage , Drug Interactions , Drug Therapy, Combination , Female , Heart Rate/drug effects , Humans , Male , Middle Aged
7.
J Am Coll Cardiol ; 18(2): 349-55, 1991 Aug.
Article in English | MEDLINE | ID: mdl-1856403

ABSTRACT

The Canadian Atrial Fibrillation Anticoagulation Study was a randomized double-blind placebo-controlled trial to assess the potential of warfarin to reduce systemic thromboembolism and its inherent risk of hemorrhage. As a result of the publication of two other "positive" studies of similar design and objective, this study was stopped early before completion of its planned recruitment of 630 patients. There were 187 patients randomized to warfarin and 191 to placebo. Permanent discontinuation of study medication occurred in 26% of warfarin-treated and 23% of placebo-treated patients. The target range of the international normalized ratio was 2 to 3. For the warfarin-treated patients, the international normalized ratio was in the target range 43.7% of the study days, above it 16.6% of the study days and below it 39.6% of the study days. Fatal or major bleeding occurred at annual rates of 2.5% in warfarin-treated and 0.5% in placebo-treated patients. Minor bleeding occurred in 16% of patients receiving warfarin and 9% receiving placebo. The primary outcome event cluster was nonlacunar stroke, noncentral nervous systemic embolism and fatal or intracranial hemorrhage. Events were included in the primary analysis of efficacy if they occurred within 28 days of permanent discontinuation of the study medication. The annual rates of the primary outcome event cluster were 3.5% in warfarin-treated and 5.2% in placebo-treated patients, with a relative risk reduction of 37% (95% confidence limits, -63.5%, 75.5%, p = 0.17).(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Atrial Fibrillation/complications , Cerebrovascular Disorders/prevention & control , Thromboembolism/prevention & control , Warfarin/therapeutic use , Aged , Canada , Cerebrovascular Disorders/epidemiology , Double-Blind Method , Female , Humans , Male , Risk Factors , Statistics as Topic , Thromboembolism/epidemiology
8.
Cardiovasc Res ; 13(3): 127-35, 1979 Mar.
Article in English | MEDLINE | ID: mdl-476739

ABSTRACT

Maximal changes in haemodynamics and segmental wall motion were seen 2 min after coronary occlusion and were examined in relation to the loading conditions of the left ventricle before occlusion in 20 open chest dogs. There was a significant inverse relationship between the preligation mean aortic pressure and the percentage decrease in stroke volume following ligation. This relationship was observed whether afterload was distributed randomly (mean aortic pressure ranging from 9.7 to 17.6 kPa [73 to 132 mmHg]) between all dogs (r = 0.65; P less than 0.001) or altered by methoxamine (+4 kPa [+30 mmHg]) and nitroprusside (-3.2 kPa [-24 mmHg]) within the same dog (r = 0.82; P less than 0.001; n = 8). Although occlusion of the anterior descending artery caused a small (+5.5%) but significant increase in end-diastolic length of the non-ischaemic epicardial segment, the capacity for compensatory ventricular dilatation was not dependent on preligation afterload. However, the capacity of the ischaemic segment to undergo systolic expansion was significantly greater (+30.2% of end-systolic segment length) in those dogs with the lowest preligation MAP (8 to 12 kPa [60 to 90 mmHg]) compared with systolic lengthening of only 15.8% in the high afterload group (15 to 18 kPa [112 to 135 mmHg]). These data indicate that the loading conditions of the left ventricle predetermine the extent of global and segmental left ventricular dysfunction during the early phase of acute ischaemic injury.


Subject(s)
Coronary Disease/physiopathology , Heart/physiopathology , Hemodynamics , Animals , Aorta, Thoracic , Blood Pressure/drug effects , Dogs , Female , Heart Ventricles/physiopathology , Male , Methoxamine/pharmacology , Myocardial Contraction , Nitroprusside/pharmacology , Stroke Volume
9.
Clin Pharmacol Ther ; 42(3): 250-3, 1987 Sep.
Article in English | MEDLINE | ID: mdl-3621780

ABSTRACT

In a multicenter trial of aspirin or sulfinpyrazone in the treatment of unstable angina, we examined the possible importance to the outcome of mentioning potential side effects in the consent form. Inclusion, in two of the three centers, of a statement outlining possible gastrointestinal side effects resulted in a sixfold increase (P less than 0.001) in the number of subjects in these centers withdrawing from the study because of subjective, minor gastrointestinal symptoms. Major gastrointestinal complications such as peptic ulcer or bleeding as diagnosed by study physicians were similar in the three centers. Furthermore, no patient discontinued therapy because of subjective, nongastrointestinal side effects. Post hoc analysis suggests that the inclusion of gastrointestinal side effects in the consent form may have increased the likelihood of patients attributing gastrointestinal symptoms to drug therapy, leading to subsequent withdrawal from the study.


Subject(s)
Angina Pectoris/drug therapy , Aspirin/adverse effects , Clinical Trials as Topic , Informed Consent , Sulfinpyrazone/adverse effects , Aspirin/therapeutic use , Digestive System/drug effects , Humans , Placebos , Sulfinpyrazone/therapeutic use , Surveys and Questionnaires
10.
Neurology ; 51(3): 674-81, 1998 Sep.
Article in English | MEDLINE | ID: mdl-9748009

ABSTRACT

OBJECTIVE: To review the risk and pathogenesis of stroke associated with nonvalvular atrial fibrillation (AF) and the efficacies and risks of stroke prevention strategies. BACKGROUND: About 16% of ischemic strokes are associated with AF; AF is an independent risk factor for stroke. METHODS: Review of the literature, focusing on 13 randomized trials of antithrombotic therapy. RESULTS: The overall risk of stroke in AF patients averages about 5%/y, but with wide variation depending on the presence of coexistent thromboembolic risk factors. AF patients with low (about 1% per year), moderate (about 3% per year), and high (about 6% per year) stroke risks have been identified, but the generalizability of risk stratification schemes to clinical practice has not been fully assessed. AF patients with prior stroke or transient ischemic attack, even if remote, are at highest risk (about 12% per year). Adjusted-dose warfarin (target International Normalized Ratio [INR] 2-3) is highly efficacious for preventing stroke in AF patients (about 70% risk reduction) and is safe for selected patients, if carefully monitored. Aspirin has a modest effect on reducing stroke (about 20% risk reduction). The numbers of AF patients that would need to be treated with warfarin instead of aspirin for 1 year to prevent one ischemic stroke are about 200, 70, and 20 for those with low, moderate and high risk, respectively. CONCLUSIONS: Many patients with nonvalvular AF have substantial rates of ischemic stroke. Stratification of stroke risk identifies AF patients who benefit most and least from lifelong anticoagulation. Warfarin is recommended for high-risk AF patients who can safely receive it. Aspirin may be indicated for those with a low stroke risk and for those who cannot receive warfarin. For AF patients considered to have a moderate risk of stroke, individual bleeding risk during anticoagulation and patient preference should particularly influence the choice of antithrombotic prophylaxis.


Subject(s)
Atrial Fibrillation/complications , Cerebrovascular Disorders/prevention & control , Aged , Aged, 80 and over , Aspirin/therapeutic use , Cerebrovascular Disorders/complications , Cerebrovascular Disorders/etiology , Clinical Trials as Topic , Female , Humans , Male , Randomized Controlled Trials as Topic , Risk Factors , Treatment Outcome , Vitamin K/antagonists & inhibitors , Warfarin/therapeutic use
11.
Am J Cardiol ; 69(4): 308-13, 1992 Feb 01.
Article in English | MEDLINE | ID: mdl-1734640

ABSTRACT

To compare 1-, 6- and 24-hour ambulatory electrocardiograms for prediction of mortality after acute myocardial infarction (AMI), all patients with AMI hospitalized in Hamilton, Ontario during 1 year were identified. There were 683 patients discharged alive after AMI. One-, 6- and 24-hour ambulatory electrocardiographic results were available in 565 patients, and follow-up mortality data at 1 year was available in 560. Mean age of the patients was 64 years; 160 (29%) had previous AMI and 105 (19%) had had congestive heart failure. One hundred and fifty-two patients (27%) were receiving beta blockers, and 31 (6%) were receiving antiarrhythmic drugs. Regression modeling of survival times up to 1 year showed that all 3 durations of recording were univariate predictors of mortality. Using greater than 10 ventricular premature complexes/hour as the criterion of a positive test, neither the 6- nor 24-hour data contained statistically significant residual explanatory power after the 1-hour data were accounted for by the model. The longer durations of recording increased sensitivity at a cost of decreased specificity. The positive and negative predictive values of the 3 durations of recording were virtually identical. The presence of ventricular tachycardia was not a significant predictor of mortality in this population. There appears to be no benefit to ambulatory electrocardiographic recordings greater than 1 hour when they are to be used for prediction of 1-year mortality after AMI.


Subject(s)
Arrhythmias, Cardiac/diagnosis , Electrocardiography, Ambulatory/methods , Myocardial Infarction/mortality , Aged , Arrhythmias, Cardiac/etiology , Female , Humans , Male , Middle Aged , Myocardial Infarction/complications , Predictive Value of Tests , Prognosis , Proportional Hazards Models , Sensitivity and Specificity , Time Factors
12.
Am J Cardiol ; 72(16): 87F-94F, 1993 Nov 26.
Article in English | MEDLINE | ID: mdl-8237836

ABSTRACT

The Canadian Amiodarone Myocardial Infarction Trial (CAMIAT) is a multicenter, triple-blind, randomized, placebo-controlled trial. Eligible patients are those found on 24-hour ambulatory electrocardiographic monitoring within 6-45 days of acute myocardial infarction to have ventricular premature depolarizations (VPDs) that are frequent (> or = 10/hr) or repetitive (> or = 1 three-beat run of ventricular tachycardia). Consenting patients are randomized to amiodarone or placebo with an oral loading dose of 10 mg/kg/day for 2 weeks; maintenance dose is 300-400 mg/day for 3.5 months, 200-300 mg/day for 4 months, and 200 mg/day for 5 or 7 days/week for 16 months. Patients are followed by alternate telephone and clinical visit at 2-month intervals for 24 months. The principal outcome is a composite of presumed arrhythmic death or resuscitated ventricular fibrillation. Outcomes are determined by an external validation committee. The anticipated rate of arrhythmic death is 7.5% over 2 years; the sample size is 1,200 patients. CAMIAT began in June 1990 and is anticipated to conclude enrollment by June 1994 and follow-up by June 1995. Recruitment rate is about 92% of projected.


Subject(s)
Amiodarone/therapeutic use , Myocardial Infarction/complications , Tachycardia/drug therapy , Canada , Humans , Pilot Projects , Proportional Hazards Models , Research Design , Tachycardia/etiology , Treatment Outcome
13.
Am J Cardiol ; 78(12): 1345-9, 1996 Dec 15.
Article in English | MEDLINE | ID: mdl-8970404

ABSTRACT

This study documents mortality from acute myocardial infarction (AMI), in hospital and at 1 year, for each of 3 selected 1-year periods in a stable community over a 13-year period beginning in 1979 and continuing into the thrombolytic era, to detect any changes occurring in conjunction with the introduction of new therapies. Every patient with AMI occurring in a geographically defined stable community (Hamilton, Ontario, Canada) in 3 1-year periods (1979 to 1980 [n = 816], 1986 to 1987 [n = 816], and 1991 to 1992 [n = 831]) was identified and clinically characterized by standardized criteria. Subsequent in-hospital and 1-year survival were ascertained prospectively. The 3 cohorts were similar in prognostic factors. Mean age was progressively greater over the study period from 63 years in 1979 to 1980, to 67 years in 1991 to 1992 (p = 0.02). There was no change in in-hospital mortality rates from 1979 to 1980 (17%) and 1986 to 1987 (16%). However, from 1986 to 1987 and 1991 to 1992, in-hospital mortality decreased from 16% to 9% (p < 0.001) and 1-year mortality decreased from 26% to 19% (p < 0.001). For patients who survived the hospital phase of AMI, 1-year mortality did not change and was between 11% and 12% in each of the 3 study periods. From 1986 to 1987 and 1991 to 1992, there was an increase in the use of thrombolytic therapy from 5% to 44% of patients. The acute use of aspirin increased from 30% to 88% and the acute use of beta blockers increased from 19% to 48% of patients. The observed increase in use of these agents could account for half of the actual mortality reduction observed. This prospective population-based survey demonstrates improved in-hospital survival after AMI associated with increased use of established effective therapies between 1987 and 1992. The 1-year mortality of hospital survivors of AMI was unchanged throughout the period of study, remaining at 11% to 12%.


Subject(s)
Hospital Mortality/trends , Myocardial Infarction/mortality , Age Factors , Aged , Humans , Middle Aged , Myocardial Infarction/drug therapy , Ontario/epidemiology , Prospective Studies , Sex Factors , Survival Rate , Thrombolytic Therapy
14.
Chest ; 99(4 Suppl): 141S-149S, 1991 Apr.
Article in English | MEDLINE | ID: mdl-2009811

ABSTRACT

The beneficial effects of coronary thrombolytic therapy may be enhanced by certain adjunctive therapies. Some of these are of proven value, some appear to offer no benefit in spite of theoretical advantages, and some remain to be evaluated in clinical trials. Acetylsalicylic acid markedly enhances the mortality reduction of thrombolytic therapy and should be used routinely. There is a strong theoretical rationale for the use of heparin, but evidence for its benefit exists primarily in small angiographic trials, and convincing clinical benefit has not yet been demonstrated. Early intravenous beta-blockers were shown in the prethrombolysis era to confer modest benefit, but extensive data on their adjuvant use with thrombolysis are available from only one trial. Intravenous nitrates were demonstrated to reduce mortality in the prethrombolysis era, and are soon to be evaluated in trials employing thrombolytic therapy. The calcium channel blockers, in spite of a variety of theoretical benefits, have proved to be of no value acutely, and in the subacute setting, only diltiazem appears to confer benefit in the subgroup of patients with non-O-wave infarction. Angiotensin-converting enzyme inhibitors are likely to be of value in survivors of acute myocardial infarction with left ventricular dysfunction, and benefits observed with acute use in experimental infarction are now being evaluated in clinical trials.


Subject(s)
Fibrinolytic Agents/therapeutic use , Thrombolytic Therapy/methods , Drug Therapy, Combination , Humans , Myocardial Infarction/drug therapy , Myocardial Infarction/pathology
15.
Chest ; 79(3): 277-85, 1981 Mar.
Article in English | MEDLINE | ID: mdl-7471859

ABSTRACT

Propranolol was administered intravenously to 12 patients with presumed acute myocardial infarction in the attempt to limit infarct size. Patients' conditions were uncomplicated (heart rate greater than or equal to 60/min, systolic blood pressure greater than or equal to 100 mm Hg, mean pulmonary capillary wedge pressure mean [PCWP] less than or equal to 20 mm mercury). The aim was to produce beta-blockade that was early, complete, and continuous. Target loading dose was achieved in seven patients and full maintenance was achieved in six patients. The remaining patients received smaller loading or maintenance doses or both because of varying degrees of bradycardia, hypotension, or elevated mean PCWP. Myocardial CK release in the propranolol group was 2651 mIU/ml +/- 843 (mean +/- SE, n = 12) vs 2987 mIU/ml +/- 422 in 21 comparison patients, a difference not statistically significant. The time to CK plateau (completion of infarction) was related to total CK release in both propranolol and comparison patients.


Subject(s)
Myocardial Infarction/drug therapy , Propranolol/administration & dosage , Adult , Aged , Creatine Kinase/blood , Female , Hemodynamics/drug effects , Humans , Injections, Intravenous , Male , Middle Aged , Models, Biological , Myocardial Infarction/blood , Myocardial Infarction/pathology , Pain/blood , Recurrence , Regression Analysis , Time Factors
16.
J Appl Physiol (1985) ; 91(3): 1372-9, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11509538

ABSTRACT

Airway remodeling with smooth muscle cell (SMC) hyperplasia is a feature of chronic asthma. We investigated the potential for tryptase, the major secretory product of human mast cells, to act as a growth factor for human airway SMCs. Because this serine protease can activate proteinase-activated receptor-2 (PAR-2), we also examined the actions of SLIGKV, a peptide agonist of PAR-2. Incubation with lung tryptase provoked a twofold increase in [(3)H]thymidine incorporation; a similar increase in cell numbers was found when we used the MTS assay. The effect was catalytic site dependent, being abolished by the protease inhibitors leupeptin and benzamidine and by heat inactivation of the enzyme. Tryptase-induced DNA synthesis was inhibited by preincubation of the cells with pertussis toxin, calphostin C, or genistein. Transduction mechanisms are thus likely to involve a pertussis toxin-sensitive G protein, protein kinase C, and tyrosine kinase. SLIGKV elicited a response on SMCs similar to that of tryptase. Tryptase could provide an important stimulus for SMC proliferation in asthmatic airways, by acting on PAR-2.


Subject(s)
Lung/cytology , Muscle, Smooth/cytology , Receptors, Thrombin/agonists , Serine Endopeptidases/pharmacology , Asthma/enzymology , Cell Division/drug effects , Cell Division/physiology , DNA/biosynthesis , Humans , In Vitro Techniques , Mast Cells/metabolism , Oligopeptides/pharmacology , Protease Inhibitors/pharmacology , Receptor, PAR-2 , Signal Transduction/drug effects , Signal Transduction/physiology , Tryptases
17.
Health Technol Assess ; 1(14): i-vi, 1-149, 1997.
Article in English | MEDLINE | ID: mdl-9483162

ABSTRACT

OBJECTIVES. To try to identify the optimal time at which to start assessing new and fast-evolving health technologies. To provide insight into factors influencing the timing of assessments and the choice of methods for assessing new and fast-changing technologies. HOW THE RESEARCH WAS CONDUCTED. A series of literature reviews were undertaken covering the general principles involved in the timing of health technology assessments (HTAs). Additionally, the reported assessments of laparoscopic cholecystectomy, chorionic villus sampling (CVS), teleradiology, teledermatology, genetic screening for predisposition to breast cancer, and gene therapy for cystic fibrosis were reviewed to try to identify the factors that influenced the timing of these assessments. Key individuals in each field were also interviewed. The selected technologies allowed comparison between those that were new and evolving and those that were relatively well-established. A bibliometric study of publication trends was also undertaken to see whether these trends would suggest points in the development of a technology that could be used as indicators that assessment should be started. RESEARCH FINDINGS. TIMING. The precise point at which assessment should start was not identified but the bibliometric study suggested that extending this approach might give useful results. For all health technologies, more regular reporting of outcomes and side-effects should be encouraged during the period after initial assessment and, where the technology is fast-changing, reassessment should take place from time to time. The precise intervals were not identified and the problem remains of deciding when a technology has changed enough to warrant reassessment. FACTORS INFLUENCING TIMING. Published reports of assessments did not generally specify the reasons for their timing, but a number of factors appear to have influenced the timing of those assessments, directly or indirectly. Product champions and opinion leaders pioneer the introduction of new technologies into clinical practice, and their reports may lead to the rapid diffusion of such technologies before they have been adequately evaluated, as was the case with laparoscopic cholecystectomy; this diffusion may limit the methods of evaluation that can then be used. It is therefore important to assess new health technologies before diffusion takes place. The extent to which regulatory control is imposed on the introduction of new health technologies can also influence the timing of assessments. Such controls might have helped to restrict the diffusion of laparoscopic cholecystectomy, making a large and widely generalisable randomised controlled trial (RCT) feasible. The source and availability of funding for studies may influence the nature and timing of trials. Many telemedicine evaluations were funded by commercial telecommunications organisations and were thus restricted in their timing (and biased towards the technological aspects of the applications) by the availability of funds. Media coverage undoubtedly has an influence although this influence is not always predictable; it may generate 'favourable' publicity about new health technologies, which can lead to immediate demands for the new technique, as was the case with laparosocpic cholecystectomy with its apparent benefits. Thus assessments should be made before media coverage exerts popular pressure on purchasers to adopt the technology and dissuades patients from participating in RCTs (because of fear they may be randomised to the standard treatment as occurred in a US trial of CVS). Innovators should also be cautious in the claims that they make to the media.(ABSTRACT TRUNCATED)


Subject(s)
Medical Laboratory Science , Technology Assessment, Biomedical , Breast Neoplasms/diagnosis , Breast Neoplasms/genetics , Cholecystectomy, Laparoscopic/methods , Cholecystectomy, Laparoscopic/standards , Chorionic Villi Sampling/methods , Chorionic Villi Sampling/standards , Clinical Trials as Topic , Cystic Fibrosis/diagnosis , Cystic Fibrosis/genetics , Diffusion of Innovation , Female , Genetic Testing/methods , Genetic Testing/standards , Humans , Medical Laboratory Science/standards , Medical Laboratory Science/trends , Pregnancy , Technology Assessment, Biomedical/standards , Technology Assessment, Biomedical/trends , Telemedicine/methods , Telemedicine/standards , United Kingdom
18.
Health Technol Assess ; 4(28): 1-89, 2000.
Article in English | MEDLINE | ID: mdl-11074396

ABSTRACT

OBJECTIVES: (1) To establish recruitment rates of newly presenting asthmatic children. (2) To establish acceptability of study protocols. (3) To pilot age-specific quality of life (QoL) assessment. (4) To assess short-term (6 months) outcomes of inhaled corticosteroids (ICS) treatment. (5) To refine sample size calculations for a definitive study. DESIGN: A randomised pragmatic longitudinal trial design was used, with no blinding or placebo, to examine early ICS introduction similar to its use in practice. Subjects were assessed at entry, 3 and 6 months. SETTING: Subjects were recruited from six general practices. Children under 6 years were assessed at the Craig Research and Investigation Unit, Royal Aberdeen Children's Hospital, or their family home, and subjects 6 years and over were assessed at their general practice. SUBJECTS: Children (aged 6 months-16 years) with symptoms suggestive of asthma/wheeze that had commenced no longer than 12 months before were identified retrospectively and prospectively from general practices. Subjects were also required to be naïve to prophylactic therapy with no other lung disease/concomitant illness. INTERVENTIONS: Subjects were randomised to ss2-agonist (ss2-only group) or ss2-agonist and ICS (ICS group) for 6 months. Physicians could later prescribe ICS in controls if needed. MAIN OUTCOME MEASURES: (1) Pulmonary function. (2) Asthma symptom diary. (3) Symptomatic health status questionnaire. (4) Caregiver's and child's QoL. (5) Growth. (6) Bone mass. (7) Bone turnover. (8) Economic issues. RESULTS: Of over 15,000 children yielded from general practice records, 11% had symptoms suggestive of asthma/wheeze, and two-thirds of these already used ICS. Of the remaining, 141 subjects met the criterion of early asthma, and 86 were randomised. Two-thirds of those randomised were < 6 years old, the males:females ratio was 2:1, and 67% had a family history of atopy. RESULTS - PHYSIOLOGICAL DEVELOPMENT: Pulmonary function did not significantly improve in the older children. Although tidal breathing measures in the pre-school children were significantly higher at 6 months in the ss2-only group, there was great variability. Incidence of wheeze and night-time cough reduced equally in both groups. Reduction of night-time symptom score and reliever use, and increase in symptom-free days were only significant in the ss2-only group. No significant differences were found in growth and bone mass between the two groups, but bone metabolism was significantly reduced at 6 months in the ICS group. RESULTS - PSYCHOLOGICAL DEVELOPMENT: The caregiver's QoL questionnaire was sensitive to child symptom changes over 3 months, but absolute impact of child symptoms on their QoL varied, whereas the child-centred questionnaire was not sensitive to change. RESULTS - ECONOMICS: There were no significant differences in medical consultation costs between the groups, but, as expected, prescription costs in the ICS group were higher over 6 months. Combined healthcare costs were significantly higher for patients assigned to ICS, but there were no significant differences in any effectiveness measures between the groups. CONCLUSIONS: Most (96%) of the proposed sample was recruited, and the low drop-out rate (8%) demonstrated acceptability of the study protocol. Most children first presenting with symptoms suggestive of asthma were < 6 years old and represented a group biased towards mild to moderate asthma, or virally induced wheeze. The caregiver's QoL questionnaire was found to better reflect a child's symptom changes than a child-centred instrument. In the short term, no adverse effects were seen on growth, but ICS treatment significantly reduced bone metabolism. Most of the young children with asthma/wheeze improved over time with ss2-agonist treatment alone, and clinical benefits of early ICS intervention amongst these children were not detected; however, there was inadequate power in this pilot study to establish this. (AB


Subject(s)
Androstadienes/therapeutic use , Anti-Asthmatic Agents/therapeutic use , Asthma/drug therapy , Asthma/physiopathology , Bone and Bones/metabolism , Bronchodilator Agents/therapeutic use , Budesonide/therapeutic use , Adolescent , Anthropometry , Asthma/economics , Asthma/psychology , Bone Density , Child , Child, Preschool , Cost-Benefit Analysis , Female , Fluticasone , Health Care Costs , Humans , Infant , Longitudinal Studies , Male , Pilot Projects , Quality of Life , Regression Analysis , Respiratory Function Tests , Statistics, Nonparametric , Surveys and Questionnaires , Treatment Outcome , United Kingdom
19.
Soc Sci Med ; 29(5): 653-8, 1989.
Article in English | MEDLINE | ID: mdl-2799414

ABSTRACT

The provision of abortion services in England and Wales is modelled with particular emphasis given to the relationship between the public and private sectors. The presence of excess demand in the public sector is established and its importance as a determinant of private demand is analysed. This study replicates the analysis and findings of one based on 1971 data with data for 1983. It is estimated that nearly one-half of the private sector demand arises as a result of excess demand in the public sector.


Subject(s)
Abortion, Legal/statistics & numerical data , Health Services Needs and Demand/statistics & numerical data , Health Services Research/statistics & numerical data , Adolescent , Adult , England , Female , Humans , Privatization , Socioeconomic Factors , State Medicine , Wales
20.
Cardiol Clin ; 12(3): 495-504, 1994 Aug.
Article in English | MEDLINE | ID: mdl-7805082

ABSTRACT

Patients with atrial fibrillation have an annual risk of stroke of 4.5%. Randomized clinical trials have reliably demonstrated that for every 1000 atrial fibrillation patients treated with warfarin, there is a reduction of 31 strokes per year at a cost of 3 major bleeds per year (including cerebral hemorrhage). Aspirin therapy is also effective for the reduction of stroke, although less so than warfarin; the bleeding risk is less with aspirin. It is possible to select patients at particularly high risk of cerebral embolism based upon simple clinical and echocardiographic parameters. Ongoing clinical trials are evaluating regimens of warfarin versus aspirin, combinations of warfarin and aspirin, and low-dose warfarin.


Subject(s)
Atrial Fibrillation/complications , Cerebrovascular Disorders/prevention & control , Embolism/prevention & control , Anticoagulants/administration & dosage , Anticoagulants/therapeutic use , Cerebrovascular Disorders/etiology , Embolism/etiology , Fibrinolytic Agents/administration & dosage , Fibrinolytic Agents/therapeutic use , Humans , Randomized Controlled Trials as Topic , Risk
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