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J R Hampton

Publications and source records attributed to J R Hampton.

At least 55 records · Page 3Linked to original sources
PubMed1997

The concept of equivalence and its application to the assessment of thrombolytic effects.

Very large clinical trials have become the norm in the evaluation of thrombolytic agents, and these 'megatrials' are administratively complex and expensive. It remains to be seen whether new thrombolytics will lead to further large reductions in fatality from an acute myocardial infarction, but new agents may well have advantages in areas such as safety and ease of administration, in addition to other clinical benefits (i.e. fewer cases of cardiac shock, heart failure and atrial fibrillation). The problem is how to introduce such new agents without a megatrial for each one. Endpoints other than fatality have some advantages and, in thrombolysis, angiographic studies are a necessary step in the development of new agents. However, such studies may not always correlate precisely with the results of mortality endpoint studies. Measurements of the resolution of ST segment elevation in myocardial infarction seem to provide a very useful method of assessing thrombolysis, but although such a technique can be applied to large numbers of patients, it cannot totally replace mortality endpoint trials. The 'equivalence' of two treatments is a clinical, not a statistical, concept, although statistical principles that allow equivalence to be investigated with medium-sized trials should be applied. Demonstrating equivalence in outcome between the new thrombolytic reteplase and streptokinase was the aim of the INJECT study.

Clinical Trials as Topic↗
PubMed1996

Quality of life, employment status, and anginal symptoms after coronary angioplasty or bypass surgery. 3-year follow-up in the Randomized Intervention Treatment of Angina (RITA) Trial.

BACKGROUND: The Randomized Intervention Treatment of Angina (RITA) trial compares initial policies of percutaneous transluminal coronary angioplasty (PTCA) and coronary artery bypass graft surgery (CABG) in 1011 patients with angina. This report assesses the impact of these revascularization procedures on angina, quality of life (according to the Nottingham Health Profile), and employment over 3 years of follow-up. METHODS AND RESULTS: Both interventions produced marked improvement in all quality-of-life dimensions (energy, pain, emotional reactions, sleep, social isolation, and mobility) and seven aspects of daily living. Patients with angina at 2 years had more quality-of-life impairment than angina-free patients, whose perceived health was similar to population norms. This reflects the close link at baseline between angina grade and quality of life. The slightly greater impairment of quality of life in PTCA compared with CABG patients is a result of their significantly higher chances of having angina, especially after 6 months. Employment status was investigated mainly for men < or = 60 years old. PTCA patients returned to work sooner (40% at 2 months compared with 10% of CABG patients), but the latter caught up by 5 months. After 2 years, 22% and 26% of CABG and PTCA patients, respectively, were not working for cardiac reasons. Patients with angina at 2 years were much more likely to be unemployed than those without. CONCLUSIONS: The impact of angina on quality of life and unemployment is greatly alleviated by PTCA or CABG. Angina is avoided more successfully with CABG, but PTCA offers a speedier return to work. Both intervention strategies then produce similar benefits for quality of life and employment over several years.

Angina Pectoris↗
PubMed1996

Beta-blockers in heart failure--the evidence from clinical trials.

There are good theoretical reasons for supposing that long-term treatment with a beta-blocker would improve symptoms and survival in patients with heart failure. A series of small studies have shown that beta-blockers improve haemodynamic parameters, but it is well known that these correlate poorly with symptoms. There is some evidence that exercise tolerance is also improved. Although there is so far no convincing evidence that beta-blockers prolong survival in patients with heart failure the development of a new generation of these drugs with additional vasodilating properties makes further large studies essential.

Adrenergic beta-Antagonists↗
PubMed1996

Mega-trials and equivalence trials: experience from the INJECT study.

As treatments for acute myocardial infarction have grown in number and effectiveness, the post-infarction mortality rate has fallen, and new therapies can provide only a small additional advantage in extending survival. To prove such an advantage of a new drug over its predecessors in the same drug class requires a trial of at least 20,000 patients. Proving 'equivalence' rather than superiority requires only 6000 patients. The INJECT trial was designed with the modest goal of determining whether the novel agent reteplase (recombinant plasminogen activator) has an effect on mortality equivalent to that of streptokinase. Between August 1993 and September 1994, 6010 patients were randomized to receive either reteplase (n = 3004) or streptokinase (n = 3006). Both treatment groups had similar rates of bleeding events, extension or recurrence of myocardial infarction, and in-hospital stroke followed by 6 months of disability. Reteplase recipients had a lower incidence of cardiac events in hospital and fewer allergic reactions. Although the number of diagnosed haemorrhagic strokes was higher in reteplase recipients, more patients receiving streptokinase had strokes of uncertain aetiology. At 35 days, the mortality rate associated with reteplase use was approximately 0.5% lower than that associated with streptokinase administration, and the upper limit of the 90% confidence interval for the difference between these rates was a superiority of streptokinase of 0.73%. Because the INJECT trial provided a probability of 0.95 that the mortality rate associated with reteplase use would be either lower than that with streptokinase administration or at most 0.73% worse, reteplase and streptokinase were proved equivalent according to the trial definition and limits.

Fibrinolytic Agents↗
PubMed1996

Mode of death in chronic heart failure. A request and proposition for more accurate classification.

The proportion of patients reported to die suddenly or from progressive circulatory failure is not consistent among studies of heart failure. Lack of an adequate or consistent classification of how patients die contributes to the current confusion over the mode of death in heart failure. Defining how patients with heart failure die could be important in developing strategies to reduce the continuing high mortality associated with this condition. We identified 27 studies that reported 50 or more deaths among patients with heart failure to ascertain how death was classified. Definitions of sudden death appeared heterogeneous and the majority of studies failed to publish or make reference to how circulatory failure was defined. A framework for the classification of the mode of death has been developed in which clear separation of the activity and place at the time of death, cause of death, mode of death, and events prior to death is made (ACME: Activity, Cause, Mode and Event). This mode of classifying death has been successfully piloted in two mortality studies; AIRE and NETWORK. Classifying mortality in this way will help identify pathways leading to death and hence suggest therapies and strategies to reduce mortality in patients with heart failure, a group of patients whose prognosis remains poor.

Adult↗
PubMed1995

Meta-analysis of randomised trials comparing coronary angioplasty with bypass surgery.

A patient with severe angina will often be eligible for either angioplasty (PTCA) or bypass surgery (CABG). Results from eight published randomised trials have been combined in a collaborative meta-analysis of 3371 patients (1661 CABG, 1710 PTCA) with a mean follow-up of 2.7 years. The total deaths in the CABG and PTCA groups were 73 and 79, respectively, with a relative risk (RR) of 1.08 (95% CI 0.79-1.50). The combined endpoint of cardiac death and non-fatal myocardial infarction occurred in 169 PTCA patients and 154 CABG patients (RR 1.10 [0.89-1.37]). Amongst patients randomised to PTCA 17.8% required additional CABG within a year, while in subsequent years the need for additional CABG was around 2% per annum. The rate of additional non-randomised interventions (PTCA and/or CABG) in the first year of follow-up was 33.7% and 3.3% in patients randomised to PTCA and CABG, respectively. The prevalence of angina after one year was considerably higher in the PTCA group (RR 1.56 [1.30-1.88]) but at 3 years this difference had attenuated (RR 1.22 [0.99-1.54]). Overall there was substantial similarity in outcome across the trials. Separate analyses for the 732 single-vessel and 2639 multivessel disease patients were largely compatible, though the rates of mortality, additional intervention, and prevalent angina were slightly lower in single vessel disease. The combined evidence comparing PTCA with CABG shows no difference in prognosis between these two initial revascularisation strategies. However, the treatments differ markedly in the subsequent requirement for additional revascularisation procedures and in the relief of angina. These results will influence the choice of revascularisation procedure in future patients with angina.

Angina Pectoris↗
PubMed1995

Open access.

Explore the source record for details and available documents.

Family Practice↗
PubMed1995

ACE for whom? Implications for clinical practice of post-infarct trials.

OBJECTIVE: To determine how many lives would be saved if patients were routinely treated with ACE inhibitors after myocardial infarction according to the criteria of four recent major clinical trials, and to estimate the costs and benefits of these approaches. DESIGN: Retrospective survey. SETTING: The Nottingham Health District. PATIENTS: Data from 7855 patients admitted between 1989 and 1990 were combined and the selection criteria of four major clinical trials (AIRE, SAVE, GISSI-3, and ISIS-4) were applied. RESULTS: Of the patients admitted in Nottingham with confirmed myocardial infarcts 39% were eligible for AIRE and 8% for SAVE. In patients with suspected myocardial infarction as defined by the major trials, 60% would have been eligible for GISSI-3 and 63% for ISIS-4. Treating appropriate patients in accordance with these trials would have saved 20 (AIRE), 3 (SAVE), 4 (GISSI-3) and 5 (ISIS-4) lives each year in Nottingham at a drug cost of 5400 pounds, 33 pounds 791, 2730 pounds, and 4116 pounds per life per year saved respectively. CONCLUSIONS: Short-term treatment with ACE inhibition appears to be cheaper but such an approach would save fewer lives. The AIRE study is the most applicable to current clinical practice but ACE inhibitors should be offered routinely to patients satisfying the criteria of any of the four major clinical trials.

Angiotensin-Converting Enzyme Inhibitors↗
PubMed1995

Variations in the use of coronary arteriography in the UK: the RITA trial coronary arteriogram register.

The Randomised Intervention Treatment of Angina (RITA) trial is comparing the effects of coronary artery bypass surgery and coronary angioplasty. During patient recruitment, the trial participants maintained a register of patients investigated by coronary arteriography. We used the register data to analyse variation in the practice and therapeutic implications of coronary arteriography between the 17 participating centres. Of 33,359 patients undergoing coronary arteriography, 85.2% had significant coronary artery disease (range 81.3%-89.3% between centres). The planned management for patients with coronary disease included coronary bypass surgery (43.3%), coronary angioplasty (15.7%) and RITA randomization (3.2%). The rate of referral for myocardial revascularization varied between centres from 47.6% to 83.4%. Multiple logistic regression analysis identified several correlates of myocardial revascularization, including the indication for investigation, extent of coronary disease and left ventricular function. After adjustment for these variables, the odds of revascularization at the different participating centres varied by a factor of 4.2. This intercentre variation in the use of revascularization procedures may reflect variation in the clinician's view of the appropriateness of myocardial revascularization in different clinical circumstances.

Age Distribution↗
PubMed1995

Acute myocardial infarction in the young--the role of smoking. The Investigators of the International Tissue Plasminogen Activator/Streptokinase Mortality Trial.

Patients who received thrombolytic therapy for acute myocardial infarction in a large international trial were divided into two groups on the basis of age; those < or = 40 years (n = 269) and those > 40 years (n = 7787). The younger group included more men (89.9% vs 75.9%, P = 0.009) and fewer patients had a history of coronary artery disease, hypertension, and diabetes mellitus. A family history of cardiovascular disease was significantly more prevalent among the young patients (53.4% vs 41.9%, P = 0.0002). Significantly more younger patients than older patients were smokers at the time of infarction (76.2% vs 42.9%, P < 0.0001) and the average number of cigarettes smoked per day was also significantly higher in young patients (27.8 +/- 14.3 vs 19.9 +/- 12.9, P < 0.01). Younger patients had a better outcome, with lower rates of cardiogenic shock (1.1% vs 7.0%, P = 0.0002), stroke (0.0% vs 1.9%, P = 0.02) and haemorrhage (1.9% vs 5.9%, P = 0.006), as well as a better Killip class at discharge (Killip > 1 in 4.5% vs 8.0%, P < 0.001), and lower hospital and 6-month mortality (0.7% and 3.1% vs 8.3% and 12%, P < 0.001, respectively). The better outcome of younger patients with acute myocardial infarction is related to their better baseline characteristics. Young patients with acute myocardial infarction have a strong family history of cardiovascular disease and a high prevalence of smoking. Smoking is the most important modifiable risk factor in these patients.

Adolescent↗
PubMed1995

How common is heart failure? Evidence from PACT (prescribing analysis and cost) data in Nottingham.

BACKGROUND: The aim of the study was to determine the prevalence of heart failure in Nottinghamshire by an analysis of prescriptions for loop diuretics. METHODS: An observational study was carried out in the Nottingham Health District, on the basis of Prescribing Analysis and Cost (PACT) data relating to nearly 400,000 kg of frusemide prescribed in the year 1991-1992 and general practitioner (GP) records on two groups of patients (total 903) prescribed frusemide. RESULTS: The total amount of frusemide prescribed on a daily basis in Nottinghamshire in 1,048,566 mg. The mean daily dose of frusemide per patient is 60 mg and the median dose 40 mg. There are between 13,107 and 26,214 patients taking frusemide in Nottinghamshire. Fifty-six per cent of patients prescribed loop diuretics by their GP fulfil diagnostic criteria for heart failure. CONCLUSION: The prevalence of heart failure in Nottinghamshire estimated from loop diuretic prescribing increases from 0.1 per cent in the age-group 30-39 years to 5.45 percent in patients aged over 90 years.

Adult↗
PubMed1994

Outcome of thrombolytic therapy in relation to hospital size and invasive cardiac services. The Investigators of the International Tissue Plasminogen Activator/Streptokinase Mortality Trial.

OBJECTIVE: The outcome of patients with acute myocardial infarction who received thrombolytic therapy was assessed in relation to the size and comprehensiveness of cardiovascular services in the admitting hospitals. METHODS: Two characteristics were obtained for each of the 438 hospitals: number of beds and in-house availability of cardiovascular services (coronary catheterization laboratory and coronary angioplasty or bypass surgery). Hospitals were grouped into four categories on the basis of size (< or = 300 vs > 300 beds) and availability of cardiovascular services. Baseline and outcome variables were compared by chi 2 analysis and logistic regression. Patients were followed up for 6 months. RESULTS: Baseline variables were comparable among hospital categories except for significant differences in the distribution of antecedent angina and time to treatment. Significantly more coronary angioplasties and bypass surgeries were performed in patients first treated in hospitals with coronary revascularization services (4.1% and 4.2% vs 1.0% and 1.9%, P < .0001). Rates of strokes (1.9% vs 1.3% and 1.6%, P = .54), hospital mortality (11.9% vs 8.5%, (P = .11), and 6-month mortality (17.0% vs 11.8% and 12.3%, P = .03) were highest among patients treated in small hospitals that had coronary revascularization facilities. The rate of invasive procedures was higher in the smaller hospitals (odds ratio [OR], 1.44; 95% confidence limits [CL], 1.11 and 1.87; P = .006) and in hospitals with coronary revascularization services (OR, 4.05; 95% CL, 3.14 and 5.22; P < .0001); hemorrhage was more frequent in centers with coronary revascularization facilities (OR, 1.39; 95% CL, 1.13 and 1.71; P = .002). Rates of hospital mortality and 6-month mortality were similar. CONCLUSIONS: Patients with acute myocardial infarction treated with thrombolytic therapy have the same mortality in small centers without in-house coronary revascularization services as in larger centers with such services.

Aged↗
PubMed1994

Health service costs of coronary angioplasty and coronary artery bypass surgery: the Randomised Intervention Treatment of Angina (RITA) trial.

For some patients with coronary artery disease, percutaneous transluminal coronary angioplasty (PTCA) is an alternative to coronary artery bypass grafting (CABG). We report comparative health service costs of these interventions within the Randomised Intervention Treatment of Angina (RITA) trial. Medications were costed at published UK prices; other resource use was costed with a set of unit costs estimated at two recruiting centres to the RITA trial, one in London and one outside. Over 2-year follow-up of 1011 patients, the estimated mean additional cost for those randomised to CABG compared with PTCA was 1050 pounds (95% CI 621 pounds-1479 pounds), with unit costs from the non-London centre, and 1823 pounds (1202 pounds-2444 pounds), with unit costs from the London centre. The initial average cost of treating a patient randomised to PTCA is about 52% of that of CABG, but after 2 years this increased to about 80% because of the greater need for subsequent interventions. The balance of advantage between PTCA and CABG may change after several years: funding has been obtained to continue RITA follow-up for 10 years. However, on the basis of patients' status at 2 years, the cost advantages of PTCA cannot be ignored. Further research is necessary to assess whether the advantage of PTCA in terms of cost is translated into one of cost-effectiveness.

Angina Pectoris↗
PubMed1994

Do women with acute myocardial infarction receive the same treatment as men?

OBJECTIVE: To determine whether women with acute myocardial infarction in the Nottingham health district receive the same therapeutic interventions as their male counterparts. DESIGN: Retrospective study. SETTING: University and City Hospitals, Nottingham. PATIENTS: All patients admitted with a suspected myocardial infarction during 1989 and 1990. MAIN OUTCOME MEASURES: Route and timing of admission to hospital, ward of admission, treatment, interventions in hospital, and mortality. RESULTS: Women with myocardial infarction took longer to arrive in hospital than men. They were less likely to be admitted to the coronary care unit and were therefore also less likely to receive thrombolytic treatment. They seemed to have more severe infarcts, with higher Killip classes, and had a slightly higher mortality during admission. They were less likely than men to receive secondary prophylaxis by being discharged taking beta blockers or aspirin. CONCLUSIONS: Survival chances both in hospital and after discharge in women with acute myocardial infarction are reduced because they do not have the same opportunity for therapeutic intervention as men.

Adrenergic beta-Antagonists↗
PubMed1994

Long-term evaluation of treatment for chronic heart failure: a 1 year comparative trial of flosequinan and captopril.

Two hundred and nine patients with moderate to severe chronic heart failure, all of whom remained symptomatic despite at least 80 mg of frusemide daily, were randomized to 12 months treatment with flosequinan or captopril. The patients were stratified into two groups, a treadmill group and a corridor walk test group, depending upon their exercise capability. Sixty-five out of 102 patients randomized to flosequinan and 43 out of 107 randomized to captopril (p < 0.001) did not complete the study. There was no difference between the groups in mortality: 19 patients died while taking flosequinan and 15 while taking captopril. Both drugs had similar effects on treadmill exercise tolerance; the mean increase at week 52 was 117 seconds in the flosequinan group and 156 seconds (p = 0.57) for the captopril group. For those patients stratified to the corridor walk test only, there was also very little difference in the improvement at 52 weeks; the mean increase for patients randomized to flosequinan was 61 meters and captopril was 75 meters (p = 0.65). However, when the walk tests from all patients are examined, captopril produced a significant improvement compared with flosequinan at week 52 (p = 0.015). Flosequinan has similar long-term efficacy to captopril but is associated with a higher incidence of adverse events.

Blood Pressure↗