401
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Feagan BG, McDonald JW, Rochon J, Laupacis A, Fedorak RN, Kinnear D, Saibil F, Groll A, Archambault A, Gillies R. Low-dose cyclosporine for the treatment of Crohn's disease. The Canadian Crohn's Relapse Prevention Trial Investigators. N Engl J Med 1994; 330:1846-51. [PMID: 8196727 DOI: 10.1056/nejm199406303302602] [Citation(s) in RCA: 170] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
BACKGROUND Long-term corticosteroid therapy for Crohn's disease is associated with important types of morbidity, such as osteoporosis. Safe and effective alternative treatments are required. Although a short-term benefit of cyclosporine in active Crohn's disease has been suggested, the long-term safety and efficacy of this treatment have not been established. METHODS We conducted a randomized, double-blind, placebo-controlled evaluation of the effect of 18 months of low-dose cyclosporine treatment on the course of Crohn's disease. Adult patients whose disease had been active within the previous two years were randomly assigned to receive cyclosporine (151 patients) or placebo (154 patients) in addition to their usual therapy. Randomization was stratified according to center and score on the Crohn's Disease Activity Index (193 patients had scores of 150 or less, and 112 had scores greater than 150). The primary outcome measure was clinically important worsening of Crohn's disease, defined as a 100-point increase in the Crohn's Disease Activity Index from the patient's base-line value. Secondary outcomes were the use of prednisone and 5-amino-salicylates, mean score on the Crohn's Disease Activity Index and mean quality-of-life score, and the need for surgery. RESULTS The condition of more patients worsened with cyclosporine than with placebo (91 of 151, or 60.3 percent, vs. 80 of 154, or 51.9 percent; P = 0.10). The median time to worsening of disease in patients receiving cyclosporine was 338 days, as compared with 492 days in patients receiving placebo (P = 0.25; relative risk, 1.22; 95 percent confidence interval, 0.86 to 1.72). Analyses of the mean Crohn's Disease Activity Index and quality-of-life scores and of the use of prednisone and 5-aminosalicylates also failed to demonstrate benefit. CONCLUSIONS In our patient population, the addition of low-dose cyclosporine to conventional treatment for Crohn's disease did not improve symptoms or reduce requirements for other forms of therapy.
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403
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Bourne RB, Rorabeck CH, Laupacis A, Feeny D, Wong C, Tugwell P, Leslie K, Bullas R. A randomized clinical trial comparing cemented to cementless total hip replacement in 250 osteoarthritic patients: the impact on health related quality of life and cost effectiveness. THE IOWA ORTHOPAEDIC JOURNAL 1994; 14:108-14. [PMID: 7719764 PMCID: PMC2329023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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404
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Rorabeck CH, Bourne RB, Laupacis A, Feeny D, Wong C, Tugwell P, Leslie K, Bullas R. A double-blind study of 250 cases comparing cemented with cementless total hip arthroplasty. Cost-effectiveness and its impact on health-related quality of life. Clin Orthop Relat Res 1994:156-64. [PMID: 8118970] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The success of a total hip arthroplasty (THA) is dependent on many more parameters than simply the prosthesis used. This study has demonstrated that a randomized controlled clinical trial of 250 patients comparing two types of hip prostheses (cemented versus cementless) with virtually complete follow-up examination is feasible. It also demonstrates that patients are willing to answer extensive quality-of-life questionnaires that allow complete assessment of the impact of hip arthroplasty on the patient's overall health-related quality of life. This study has also demonstrated that THA is an extremely effective intervention when one assesses its ability to impact on patients health-related quality of life with no difference between cement versus cementless at two years' follow-up examination.
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405
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Sauvé JS, Laupacis A, Ostbye T, Feagan B, Sackett DL. The rational clinical examination. Does this patient have a clinically important carotid bruit? JAMA 1993; 270:2843-5. [PMID: 8133624 DOI: 10.1001/jama.1993.03510230081040] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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406
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407
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Laupacis A, Bourne R, Rorabeck C, Feeny D, Wong C, Tugwell P, Leslie K, Bullas R. The effect of elective total hip replacement on health-related quality of life. J Bone Joint Surg Am 1993; 75:1619-26. [PMID: 8245054 DOI: 10.2106/00004623-199311000-00006] [Citation(s) in RCA: 379] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The effect of total hip replacement on the health-related quality of life of patients who have osteoarthrosis was examined as part of a randomized, controlled trial comparing femoral head prostheses that were inserted with or without cement. One hundred and eighty-eight patients were followed for three months: 179 of them, for six months; 156, for one year; and ninety, for two years. The health-related quality of life was assessed with use of the Harris hip score, the Merle d'Aubigné hip score, the Sickness Impact Profile, the Western Ontario and McMaster University (WOMAC) Osteoarthritis Index, the McMaster--Toronto Arthritis (MACTAR) Patient Preference Disability Questionnaire, and the time trade-off technique as a measure of utility. Patients also took the six-minute-walk test. The mean age of the patients in the study was sixty-four years (range, forty to seventy-five years); ninety-seven patients (53 per cent) were men and ninety-four (50 per cent) had a prosthesis inserted with cement. Only three of 188 patients refused to return for quality-of-life assessments. There was significant improvement in all health-related quality-of-life measures and in the six-minute-walk test after the operation (p < 0.01 for all items, except for the work dimension of the Sickness Impact Profile at three months [p = 0.07]). Most of the improvement had occurred by three months postoperatively.(ABSTRACT TRUNCATED AT 250 WORDS)
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408
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Turpie AG, Gent M, Laupacis A, Latour Y, Gunstensen J, Basile F, Klimek M, Hirsh J. A comparison of aspirin with placebo in patients treated with warfarin after heart-valve replacement. N Engl J Med 1993; 329:524-9. [PMID: 8336751 DOI: 10.1056/nejm199308193290802] [Citation(s) in RCA: 359] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
BACKGROUND Despite the use of warfarin, major systemic embolism remains an important complication in patients with heart-valve replacement. Although the addition of antiplatelet agents has the potential to reduce this complication, their efficacy and safety when given in combination with warfarin are uncertain. METHODS In a randomized, double-blind, placebo-controlled trial, we assessed the efficacy and safety of adding aspirin (100 mg per day) to warfarin treatment (target international normalized ratio, 3.0 to 4.5) in 370 patients with mechanical heart valves or with tissue valves plus atrial fibrillation or a history of thromboembolism. RESULTS A total of 186 patients were randomly assigned to aspirin and 184 to placebo, and they were followed for up to 4 years (average, 2.5). Major systemic embolism or death from vascular causes occurred in 6 aspirin-treated patients (1.9 percent per year) and 24 placebo-treated patients (8.5 percent per year) (risk reduction with aspirin, 77 percent; 95 percent confidence interval, 44 to 91 percent; P < 0.001). Major systemic embolism, nonfatal intracranial hemorrhage, or death from hemorrhage or vascular causes occurred in 12 patients assigned to aspirin (3.9 percent per year) and 28 patients assigned to placebo (9.9 percent per year) (risk reduction, 61 per cent; 95 percent confidence interval, 24 to 80 percent; P = 0.005); major systemic embolism or death from any cause occurred in 13 patients (4.2 percent) and 33 patients (11.7 percent), respectively (risk reduction, 65 percent; 95 percent confidence interval, 33 to 82 percent; P < 0.001); and death from all causes occurred in 9 patients (2.8 percent) and 22 patients (7.4 percent), respectively (risk reduction, 63 percent; 95 percent confidence interval, 19 to 83 percent; P = 0.01). Bleeding occurred in 71 patients in the aspirin group (35.0 percent), as compared with 49 patients in the placebo group (22.0 percent) (increase in risk, 55 percent; 95 percent confidence interval, 8 to 124 percent; P = 0.02); major bleeding occurred in 24 and 19 patients, respectively (increase in risk, 27 percent; 95 percent confidence interval, -30 to 132 percent; P = 0.43). CONCLUSIONS In patients with mechanical heart valves and high-risk patients with prosthetic tissue valves, the addition of aspirin to warfarin therapy reduced mortality, particularly mortality from vascular causes, together with major systemic embolism. Although there was some increase in bleeding, the risk of the combined treatment was more than offset by the considerable benefit.
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409
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Laupacis A, Feagan B, Wong C. Effectiveness of perioperative recombinant human erythropoietin in elective hip replacement. COPES Study Group. Lancet 1993; 342:378. [PMID: 8101624 DOI: 10.1016/0140-6736(93)91527-s] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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410
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Laupacis A, Feeny D, Detsky AS, Tugwell PX. Tentative guidelines for using clinical and economic evaluations revisited. CMAJ 1993; 148:927-9. [PMID: 8448707 PMCID: PMC1490721] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
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411
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Hayward RS, Laupacis A. Initiating, conducting and maintaining guidelines development programs. CMAJ 1993; 148:507-12. [PMID: 8431814 PMCID: PMC1490514] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
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412
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Laupacis A, Pus N, Muirhead N, Wong C, Ferguson B, Keown P. Disease-specific questionnaire for patients with a renal transplant. Nephron Clin Pract 1993; 64:226-31. [PMID: 8321355 DOI: 10.1159/000187318] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
A disease-specific questionnaire to assess the quality of life of renal transplant recipients was developed. A list of items of potential relevance to these patients was created and 50 transplant recipients rated the importance of each item. A combination of factor analysis and clinical judgment was then used to create the final questionnaire which consists of 25 questions in 5 dimensions (physical symptoms, fatigue, uncertainty/fear, appearance and emotions). The physical symptoms dimension is patient specific. All questions are scored on a 7-point Likert scale. The reproducibility of the questionnaire when it was administered to stable transplant recipients was high (intraclass correlation coefficients between 0.82 and 0.91 for the 5 dimensions). The scores of all dimensions except appearance improved 6 months after transplantation, when compared to pretransplantation scores. Patients who had a well-functioning graft (creatinine < 250 mmol/l) had higher scores than those with poorly functioning grafts. This questionnaire is easy to administer and is valid, reproducible in stable patients and responsive to change.
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413
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Cook DJ, Guyatt GH, Laupacis A, Sackett DL. Rules of evidence and clinical recommendations on the use of antithrombotic agents. Chest 1992. [PMID: 1395818 DOI: 10.1378/chest.102.4_supplement.305s] [Citation(s) in RCA: 59] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
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414
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Cook DJ, Guyatt GH, Laupacis A, Sackett DL. Rules of evidence and clinical recommendations on the use of antithrombotic agents [published erratum appears in Chest 1994 Feb;105(2):647]. Chest 1992. [DOI: 10.1378/chest.102.4.305s] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
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415
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416
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Laupacis A. Erythropoietin: a hormone finds a purpose. J Rheumatol 1992; 19:1007. [PMID: 1404115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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417
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Sheingold S, Churchill D, Muirhead N, Laupacis A, Labelle R, Goeree R. The impact of recombinant human erythropoietin on medical care costs for hemodialysis patients in Canada. Soc Sci Med 1992; 34:983-91. [PMID: 1631611 DOI: 10.1016/0277-9536(92)90129-e] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Recombinant human erythropoietin (r-HuEPO) is an established and effective therapy for anemia related to end stage renal disease. In addition to its clinical effects, it has been associated with significant improvements in quality of life for anemic hemodialysis patients. The therapy's impact on overall medical care expenditures for these patients remains uncertain, however. In this study, we examine the costs of r-HuEPO as well as potential offsetting reductions in other medical care costs that might result from the therapy. We used data from a randomized clinical trial, a longitudinal study of hemodialysis patients and the clinical literature to estimate the impact of r-HuEPO on transfusion requirements, transfusion-related illness, hospitalization and transplant success for these patients. We estimate that for patients that otherwise would be transfused, the therapy would reduce blood requirements by nearly 10 units per patient annually and hospital use by 8 days per year. In addition, increased transplant success due to r-HuEPO might result in 150 fewer patient months of dialysis treatments each year. Comparing the dollar value of these reductions with the cost of therapy yields a base case net increase in medical care expenditures of $3425 per patient year. Under varying assumptions, the estimates range from a net cost of $8320 to a net saving of $1775 per patient year.
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418
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Laupacis A, Feeny D, Detsky AS, Tugwell PX. How attractive does a new technology have to be to warrant adoption and utilization? Tentative guidelines for using clinical and economic evaluations. CMAJ 1992; 146:473-81. [PMID: 1306034 PMCID: PMC1488412] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Because economic evaluations of health care services are being published with increasing frequency it is important to (a) evaluate them rigorously and (b) compare the net benefit of the application of one technology with that of others. Four "levels of evidence" that rate economic evaluations on the basis of their methodologic rigour are proposed. They are based on the quality of the methods used to estimate clinical effectiveness, quality of life and costs. With the use of the magnitude of the incremental net benefit of a technology, therapies can also be classified into five "grades of recommendation." A grade A technology is both more effective and cheaper than the existing one, whereas a grade E technology is less or equally effective and more costly. Those of grades B through D are more effective and more costly. A grade B technology costs less than $20,000 per quality-adjusted life-year (QALY), a grade C one $20,000 to $100,000/QALY and a grade D one more than $100,000/QALY. Many issues other than cost effectiveness, such as ethical and political considerations, affect the implementation of a new technology. However, it is hoped that these guidelines will provide a framework with which to interpret economic evaluations and to identify additional information that will be useful in making sound decisions on the adoption and utilization of health care services.
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419
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Laupacis A, Muirhead N, Keown P, Wong C. A disease-specific questionnaire for assessing quality of life in patients on hemodialysis. Nephron Clin Pract 1992; 60:302-6. [PMID: 1565182 DOI: 10.1159/000186769] [Citation(s) in RCA: 98] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
A disease-specific questionnaire was developed for patients receiving chronic hemodialysis by interviewing patients to determine which aspects of their quality of life were adversely affected by their disease. The final questionnaire contained 26 questions in five dimensions (physical symptoms, fatigue, depression, relationships with others, frustration). The questionnaire demonstrated construct validity when compared with the Sickness Impact Profile, time trade-off technique and an exercise stress test. It was reproducible in stable, placebo-treated patients (correlation coefficient 0.85-0.98 for the 5 dimensions). It was more responsive than other measures in detecting an improvement with erythropoietin therapy in a randomized, placebo-controlled trial. This questionnaire should be useful for the assessment of the effect of various interventions upon the quality of life of hemodialysis patients.
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420
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Laupacis A, Connolly SJ, Gent M, Roberts RS, Cairns J, Joyner C. How should results from completed studies influence ongoing clinical trials? The CAFA Study experience. Ann Intern Med 1991; 115:818-22. [PMID: 1834003 DOI: 10.7326/0003-4819-115-10-818] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Seven randomized studies during the past 5 years have evaluated or are evaluating the efficacy of warfarin or aspirin or both in decreasing the risk of embolic events in patients with nonrheumatic atrial fibrillation. By March 1990, two of the studies had been published, both of which showed a statistically significant decrease in embolic events in patients treated with warfarin and a low rate of major bleeding events. The investigators associated with the other ongoing studies were forced to consider how these results should affect the decision to recruit and continue follow-up of patients in their own studies. The Steering Committee of the Canadian Atrial Fibrillation Anticoagulation (CAFA) study thought the newly published results from other studies were valid, clinically important, and generalizable. The committee considered the following options for the CAFA study: continue patient recruitment as planned, provide the data available in CAFA to its External Safety and Efficacy Monitoring Committee for analysis to determine whether the CAFA data already showed a benefit of warfarin, stop patient recruitment but continue to follow patients in the group to which they were assigned, stop the trial immediately and perform a final analysis, and attempt to perform a meta-analysis of all data available from all trials. The Steering Committee of CAFA decided that the evidence of benefit with warfarin, from the two published studies, was sufficiently compelling as to stop recruitment into CAFA without any preliminary examination of the CAFA data.
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421
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Mahon J, Steel K, Feagan BG, Laupacis A, Pederson LL. Use of acetylsalicylic acid by physicians and in the community. CMAJ 1991; 145:1107-16. [PMID: 1751930 PMCID: PMC1335868] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
OBJECTIVE To determine physicians' attitudes toward prescribing acetylsalicylic acid (ASA), physicians' own use of ASA and the prevalence of ASA use in the community following the trials of ASA for primary prevention of coronary heart disease. DESIGN Random sample surveys of physicians and the general public by mail and telephone respectively and a mail survey of a selected panel of expert cardiologists and neurologists. SETTING London, Ont., and surrounding Middlesex County. PARTICIPANTS A total of 210 physicians (77% of eligible subjects), including family practitioners and most types of specialists, with an active medical licence and 666 English-speaking people (75% of eligible subjects) aged 18 years or more living in a household with active, listed telephone service. MAIN OUTCOME MEASURE Long-term ASA use (at least 80 mg on alternate days for 4 or more consecutive weeks) for the treatment of atherosclerosis. MAIN RESULTS Sampled physicians and experts agreed that long-term ASA therapy was indicated in patients with unstable angina, a transient ischemic episode or recent myocardial infarction but not for primary prevention in healthy middle-aged men and women at low risk for ischemic vascular disease. Both groups were uncertain about the role of ASA in primary prevention in asymptomatic people with risk factors for atherosclerosis. Nine (16%) of the 55 male physicians aged 50 years or more took ASA routinely for primary prevention. In the community survey almost all those who used ASA routinely were 50 years or older. The proportions of men and women in this age group who used ASA routinely for any reason were 19% (95% confidence limits [CLs] 11 and 28) and 14% (95% CLs 8 and 19) respectively; the proportions of men and women who used ASA routinely and apparently for primary prevention were 8% and 1% respectively. A total of 43% (95% CLs 30 and 57) of those with apparent ischemic vascular disease took ASA routinely. Medically unsupervised long-term ASA use for primary or secondary prevention of ischemic vascular disease was uncommon (reported by 2% of those who used the drug routinely). CONCLUSIONS Physicians generally agree on a role for long-term ASA therapy in the secondary prevention of ischemic vascular disease. However, the prevalence of long-term ASA use in people with overt atherosclerosis in the community may be less than optimal. The role of the drug in the primary prevention of ischemic vascular disease is less accepted. Long-term ASA use in the community for primary prevention is uncommon but detectable.
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422
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Laupacis A. Results from clinical trials: How should they influence other ongoing clinical studies? ACTA ACUST UNITED AC 1991. [DOI: 10.1016/0197-2456(91)90116-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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423
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Laupacis A, Wong C, Churchill D. The use of generic and specific quality-of-life measures in hemodialysis patients treated with erythropoietin. The Canadian Erythropoietin Study Group. CONTROLLED CLINICAL TRIALS 1991; 12:168S-179S. [PMID: 1663853 DOI: 10.1016/s0197-2456(05)80021-2] [Citation(s) in RCA: 86] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The effect of recombinant human erythropoietin (EPO) on the quality of life and exercise capacity of 118 hemodialysis patients was assessed in a randomized, double-masked placebo-controlled trial. Patients were randomized into three groups: 1) placebo, 2) EPO to achieve a hemoglobin of 95-110 g/L and 3) EPO to achieve a hemoglobin of 115-130 g/L. Patients were followed for six months. Quality of life was assessed using a disease-specific measure [the Kidney Disease Questionnaire (KDQ)] and two generic measures [Sickness Impact Profile (SIP) and the Time Trade OFF (TTO)]. The KDQ contains five dimensions. Functional capacity was assessed with a Six-Minute Walk test (SMW) and an Exercise Stress Test (EST). The mean hemoglobin at six months was 74, 102, and 117 gm/l in groups one, two and three, respectively. There was a marked improvement in quality of life with EPO therapy, but no difference between groups 2 and 3. The outcome measure that was the most responsive to change was the KDQ (P less than .001 for the fatigue and physical symptoms dimensions). The aggregate global (P less than .02) and physical (P = .005) scores of the SIP improved with EPO therapy, the psychosocial score did not. There was no improvement in the TTO. There was an improvement in the EST (P = .02) but not in the SMW. The reproducibility of the outcome measures in placebo-treated patients varied between 0.80 and 0.98 (intra-class correlation coefficient). The correlation among the outcome measures at six months was statistically significant in most cases, as was the correlation of change scores between baseline and six months.
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424
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Connolly SJ, Laupacis A, Gent M, Roberts RS, Cairns JA, Joyner C. Canadian Atrial Fibrillation Anticoagulation (CAFA) Study. J Am Coll Cardiol 1991; 18:349-55. [PMID: 1856403 DOI: 10.1016/0735-1097(91)90585-w] [Citation(s) in RCA: 726] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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)
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425
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Laupacis A. A randomized double-blind study of recombinant human erythropoietin in anaemic hemodialysis patients. Canadian Erythropoietin Study Group. Transplant Proc 1991; 23:1825-6. [PMID: 2053167] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
This study suggests that both the quality of life and exercise capacity of anaemic hemodialysis patients is improved with EPO therapy. This was seen most convincingly in the dimensions of fatigue and physical symptoms. There was no difference in improvement in quality of life or exercise capacity between patients with a mean hemoglobin level of 102 g/L and those with a mean hemoglobin level of 117 g/L. There was an increase in diastolic blood pressure in the EPO-treated patients, especially those randomized to the high EPO group.
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