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At least 253 records · Page 14Linked to original sources
PubMed1985

Participants in prospective, randomized clinical trials for resected non-small cell lung cancer have improved survival compared with nonparticipants in such trials.

The survival of 78 patients with resected non-small cell lung cancer entered in prospective, randomized investigational trials is compared to that of a population-based group of control patients not included in such trials. The survival of trial patients is significantly better than that of controls (P less than 0.001). This survival advantage for trial participants is most apparent among late Stage I patients, and is observed after matching for known prognostic factors (i.e., primary tumor size, nodal status, tumor histology) and after adjusting in the analysis for age, sex, and the administration of radiation therapy. Several explanations for the improved outcome for trial patients are explored, including differences in preoperative evaluation, staging, surgical technique, placebo effects, and patient motivation. These results suggest the possibility that inclusion in these controlled cancer trials may have had an inherent advantage for all participants.

Adult↗
PubMed1991

Rationale and design of a secondary prevention trial of lowering normal plasma cholesterol levels after acute myocardial infarction: the Cholesterol and Recurrent Events trial (CARE)

Recent clinical trials of primary and secondary prevention of cardiovascular disease have demonstrated that lowering plasma cholesterol decreases the incidence of coronary heart disease in patients with elevated plasma cholesterol. However, it is not known whether patients with established coronary artery disease and normal plasma cholesterol can be benefited. Several previous prevention trials reviewed in this report found that patients who had plasma cholesterol levels at baseline in the upper portion of the eligibility range (e.g., greater than 240 mg/dl) received greater benefit from hypolipidemic diet or drug therapy than patients who had lower plasma cholesterol levels at baseline. The recent availability of drugs that are more potent and less prone to cause adverse reactions than previous regimens permits this important question to be addressed. The Cholesterol and Recurrent Events trial is testing whether pravastatin, a hydroxymethylglutaryl coenzyme A reductase inhibitor, will decrease the sum of fatal coronary heart disease and nonfatal myocardial infarction (MI) in patients who have recovered from a MI and who have normal total cholesterol levels. Fatal cardiovascular disease and total mortality are important secondary end points. The trial is enrolling 4,000 men and women from 80 centers throughout North America, age 21 to 75 years, who have survived MI for 3 to 20 months, who have plasma total cholesterol less than 240 mg/dl (6.2 mmol/liter) and low-density cholesterol of 115 to 174 mg/dl (3.0 to 4.5 mmol/liter), and who are representative of the general population of patients with MI. Patients are randomized to either active or inactive drug therapy. Active therapy consists of pravastatin, 40 mg/day, designed to achieve an average decrease in low-density lipoprotein cholesterol of approximately 30%, and an increase in high-density lipoprotein of 5%. The average duration of follow-up will be greater than or equal to 5 years. To protect against a lower than expected rate of recurrent events, the trial will be continued until a predetermined fixed number of coronary heart disease events occurs in the entire cohort so that the original sensitivity of the trial will be maintained.

Adult↗
PubMed1990

Isotretinoin-basal cell carcinoma prevention trial. Design, recruitment results, and baseline characteristics of the trial participants. The ISO-BCC Study Group.

The Isotretinoin-Basal Cell Carcinoma Prevention Trial (ISO-BCC Study) is a double-masked, randomized, placebo controlled, multicenter clinical trial. It is the first intramural cancer chemoprevention trial sponsored by the Division of Cancer Prevention and Control of the National Cancer Institute. This trial was designed to evaluate the effectiveness of chronic administration of low dosage levels (10 mg) of a synthetic retinoid, isotretinoin, in reducing the incidence of basal cell carcinoma in a high-risk population and to determine the incidence and severity of side effects associated with this long-term treatment. Between 1984 and 1987, eight clinical centers enrolled 981 participants between the ages of 40 and 75, who had two or more biopsy proven basal cell carcinomas in the 5 years before trial entry. This article describes the trial design, recruitment results, and baseline characteristics of the participant population in the ISO-BCC Study.

Adult↗
PubMed2006

Design paper: the DEMO trial: a randomized, parallel-group, observer-blinded clinical trial of aerobic versus non-aerobic versus relaxation training for patients with light to moderate depression.

BACKGROUND: In western countries, the yearly incidence of depression is estimated to be 3-5% and the lifetime prevalence is 17%. In patient populations with chronic diseases the point prevalence may be 20%. Depression is associated with increased risk for various conditions such as osteoporoses, cardiovascular diseases, and dementia. WHO stated in 2000 that depression was the fourth leading cause of disease burden in terms of disability. In 2000 the cost of depression in the US was estimated to 83 billion dollars. A predominance of trials suggests that physical exercise has a positive effect on depressive symptoms. However, a meta-analysis from 2001 stated: "The effectiveness of exercise in reducing symptoms of depression cannot be determined because of a lack of good quality research on clinical populations with adequate follow-up." OBJECTIVES: The major objective for this randomized trial is to compare the effect of non-aerobic, aerobic, and relaxation training on depressive symptoms using the blindly assessed Hamilton depression scale (HAM-D(17)) as primary outcome. The secondary outcome is the effect of the intervention on working status (i.e., lost days from work, employed/unemployed) and the tertiary outcomes consist of biological responses. DESIGN: The trial is designed as a randomized, parallel-group, observer-blinded clinical trial. Patients are recruited through general practitioners and psychiatrist and randomized to three different interventions: 1) non-aerobic, -- progressive resistance training, 2) aerobic training, -- cardio respiratory fitness, and 3) relaxation training with minimal impact on strength or cardio respiratory fitness. Training for all three groups takes place twice a week for 4 months. Evaluation of patients' symptoms takes place four and 12 months after inclusion. The trial is designed to include 45 patients in each group. Statistical analysis will be done as intention to treat (all randomized patients). Results from the DEMO trial will be reported according to the CONSORT guidelines in 2008-2009.

Adolescent↗
PubMed2003

Impact of lesion complexity on the capacity of a trial to detect differences in stent performance: results from the ISAR-STEREO trial.

BACKGROUND: A number of stent-versus-stent trials have not been able to disclose differences in stent performance. It has been hypothesized that the selection of patient subsets with simple lesion morphologies may have masked differences among the stent designs under testing. The randomized Intracoronary Stenting and Angiographic Results Strut Thickness Effect on Restenosis Outcome (ISAR-STEREO) trial has shown that a reduced stent strut thickness is associated with a reduced risk for restenosis. The rationale of this study was to investigate the role of lesion complexity on the capacity of a stent-versus-stent trial to distinguish between superior and inferior stents. METHODS: In the ISAR-STEREO trial, 651 patients were randomly assigned to receive either a thin-strut (n = 326) or a thick-strut stent (n = 325) with a comparable stent design. Restenosis, defined as a > or =50% diameter stenosis at follow-up angiography, was analyzed according to the lesion complexity, which was assessed with the use of the American College of Cardiology/American Heart Association classification system. RESULTS: The restenosis rate did not differ between stent designs in patients with noncomplex lesions (type A or B(1); restenosis rate: 16.7% vs 16.7%, P = 1.0 for thin-strut vs thick-strut stents). In patients with complex lesions (type B2 or C), there was a significant reduction in restenosis in the thin-strut stent group (restenosis rate: 14.5% vs 29.0%; P <.01 for thin-strut vs thick-strut stents). CONCLUSIONS: The results of this study suggest that the potential to detect differences in the risk for restenosis in stent-versus-stent trials is strongly dependent on the inclusion of patients with complex lesions. These findings may be relevant when planning new stent-versus-stent trials.

Aged↗
PubMed2000

Coordination and management of a large multicenter screening trial: the Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial.

The Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial is a large and complex multi-institutional, multifaceted organization with a 20-year horizon. The implementation of the trial began with the creation of an organizational structure that supports strong leadership, cooperation, and effective communication among the trial collaborators including an operational framework for the development, review, and pretest of instruments, data collection, and management procedures; the setting of high-quality standards for training of trial staff; and the development of a comprehensive assessment plan for evaluation of all trial activities. This paper describes the process and methods used in the coordination and management of the PLCO trial. These include the role of the steering committee and its subcommittees and working groups, the establishment of regular and ad hoc communications among collaborators, the training of screening center coordinators and examiners, the PLCO manual of operations and procedures, and the development and implementation of a comprehensive quality assurance plan.

Colorectal Neoplasms↗
PubMed2003

An open-label randomized clinical trial of novel therapeutic strategies for HIV-infected patients in whom antiretroviral therapy has failed: rationale and design of the OPTIMA Trial.

OPTIMA (OPTions In Management with Antiretrovirals) is a clinical trial with a factorial randomization to evaluate the hypotheses that mega-antiretroviral therapy (ART) consisting of five or more anti-HIV drugs compared to standard-ART consisting of four or fewer anti-HIV drugs and a 3-month antiretroviral drug-free period (ARDFP) compared to no ARDFP will delay the occurrence of new or recurrent acquired immunodeficiency syndrome events or death, and prove to be more cost-effective in treating human immunodeficiency virus-infected individuals previously exposed to ART drugs from the current three main classes. The aim is to randomize 1,700 participants to four treatment strategy arms: (1) ARDFP+standard-ART; (2) ARDFP+mega-ART; (3) no ARDFP+standard-ART; (4) no ARDFP+mega-ART. The planned study duration is 3.5 years with 2.5 years of intake and a minimum 1 year of follow-up. The OPTIMA Trial was initiated in June 2001 at 30 U.S. Department of Veterans' Affairs hospitals, 22 hospitals in Canada, and 25 hospitals in the United Kingdom. This is the first large-scale, multicenter, randomized controlled trial to compare the relative efficacy of these different therapeutic strategies. We discuss the rationale behind the OPTIMA Trial design as well as the issues arising from the conduct of a trial that involves three national clinical trial agencies.

Adult↗
PubMed2004

Anastrozole ('Arimidex') versus tamoxifen as first-line therapy in postmenopausal women with advanced breast cancer: results of the double-blind cross-over SAKK trial 21/95--a sub-study of the TARGET (Tamoxifen or 'Arimidex' Randomized Group Efficacy and Tolerability) trial.

It is desirable to identify the most effective sequence of endocrine therapies for the treatment of postmenopausal women with advanced, hormone-responsive breast cancer. In a retrospective analysis of two large, randomized, comparative Phase III trials in this patient population, the Tamoxifen or 'Arimidex' Randomized Group Efficacy and Tolerability (TARGET) trial and the North American trial, we ascertained that tumors responding to anastrozole as first-line therapy may subsequently respond to tamoxifen as second-line therapy. In a double-blind cross-over trial, the SAKK 21/95 sub-trial (including patients from the Swiss centres in the TARGET trial), we further investigated the clinical impact of anastrozole followed by tamoxifen compared with that of tamoxifen followed by anastrozole. Patients with locally advanced or metastatic breast cancer who had continued on randomized treatment until objective disease progression and were still considered suitable for endocrine therapy, could continue on blinded therapy crossing-over to the alternative treatment. They were assessed for time to progression (TTP) from treatment randomization, TTP after crossing-over treatments, time from randomization to progression after crossing-over treatments and overall survival. Median TTP from randomization for patients receiving first-line treatment with anastrozole (n = 31) and tamoxifen (n = 29) was 11.3 and 8.3 months, respectively, p = 0.75. Median TTP from treatment cross-over was 6.7 months for tamoxifen after progression on anastrozole (n = 19) and 5.7 months for anastrozole after progression on tamoxifen (n = 18), while median time from randomization to second progression was 28.2 and 19.5 months, respectively. Overall survival from randomization for the anastrozole-tamoxifen sequence and the tamoxifen-anastrozole sequence was 69.7 versus 59.3 months, respectively, p = 0.10. The relative risk of death was higher for the tamoxifen followed by anastrozole sequence (1.63; 95% confidence interval [CI] 0.89-2.98). Tamoxifen is an effective second-line therapy after anastrozole. Our data, together with the better tolerability profile of anastrozole compared with tamoxifen, support the use of anastrozole as first-line therapy for advanced breast cancer in postmenopausal women with hormone receptor-positive tumors. Treatment with tamoxifen may still be useful upon subsequent progression.

Adult↗
PubMed2003

Representativeness of trial populations: an example from a trial of adenotonsillectomy in children.

OBJECTIVE: To compare demographic and disease-specific characteristics of children included in a trial of the effectiveness of adenotonsillectomy with those of children who, although eligible, were not randomized. MATERIAL AND METHODS: Characteristics were compared between (i) randomized children (n = 270); (ii) eligible children whose parents immediately decided not to participate (n = 243); and (iii) eligible children whose parents were informed about the trial by a member of the study team but did not give their informed consent for participation in the trial (n = 406). RESULTS: Statistically significant but relatively small differences were observed between the groups. Notably. breathing difficulties at night and abnormal appearance of the tonsils were more prevalent among eligible children whose parents immediately refused participation in the trial than in the other two groups. In contrast, cervical lymphadenopathy and previous ENT surgery were less prevalent among eligible children whose parents immediately refused participation in the trial. CONCLUSION: Few and relatively small differences were observed between randomized and eligible, non-randomized children. The trial population appears to be representative of the relevant patient domain, i.e. children currently undergoing adenotonsillectomy in The Netherlands.

Adenoidectomy↗
PubMed2004

Vasectomy techniques for male sterilization: systematic Cochrane review of randomized controlled trials and controlled clinical trials.

BACKGROUND: The review aimed to compare the effectiveness, safety and acceptability of vasectomy techniques for male sterilization. METHODS: We searched five computerized databases and reference lists of relevant articles and book chapters for randomized controlled trials (RCTs) and controlled clinical trials (CCTs) comparing vasectomy techniques. Two reviewers independently extracted data from eligible articles. RESULTS: Two poor-quality trials compared vas occlusion with clips versus a conventional technique, and four poor-quality trials examined vas irrigation with water versus no irrigation or irrigation with euflavine. No significant differences regarding the primary outcome of time to azoospermia were found. However, one trial reported fewer median number of ejaculations to azoospermia with euflavine rather than water irrigation. An interim report of a high-quality trial comparing vasectomy with and without fascial interposition found more azoospermia with fascial interposition but also more surgical difficulties. CONCLUSIONS: No conclusions can be reached regarding the effectiveness, safety and acceptability of vas occlusion techniques or vas irrigation since only low-quality, underpowered studies were available. Fascial interposition had improved vasectomy success but also increased surgical difficulty. High-quality, adequately reported RCTs are required. More work is also needed in the standardization of follow-up protocols, evaluation of vasectomy success and failure, recanalization and analytical methods.

Controlled Clinical Trials as Topic↗
PubMed2005

Prostate Cancer Screening in the Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial: findings from the initial screening round of a randomized trial.

BACKGROUND: The benefit of screening for prostate cancer using prostate-specific antigen (PSA) testing and digital rectal examination (DRE) is uncertain and is under evaluation in a randomized prospective trial, the Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial. Although the final results are several years away, the initial round of screening is complete. We describe the population enrolled in the PLCO trial, their baseline PSA and DRE screening results, and diagnostic follow-up results during the first year of follow-up. METHODS: A total of 38,350 men were randomly assigned to the screening arm of the PLCO trial from November 1993 through June 2001. Men were advised to seek diagnostic follow-up from their primary care provider if their DRE was suspicious for cancer and/or if their serum PSA level was higher than 4 ng/mL. PLCO trial staff obtained records related to diagnostic follow-up. RESULTS: Compliance with both screening tests was high (more than 89%). At screening, 7.5% of men had a positive DRE (i.e., suspicious for cancer) and 7.9% had a PSA level higher than 4 ng/mL. Of the men with positive screening tests, 74.2% underwent additional diagnostic testing, and 31.5% underwent a prostatic biopsy within 1 year. Overall, 1.4% of the men in the screening arm were diagnosed with prostate cancer, the majority of whom had clinically localized cancer. These compliance, biopsy, and cancer detection rates appear to be representative of contemporary practice patterns. CONCLUSION: The PLCO trial is evaluating PSA- and DRE-based screening for prostate cancer in a clinically valid manner. Whether such screening will result in a reduction of prostate cancer mortality cannot be answered until the randomized comparison is completed.

Aged↗
PubMed2003

The National Institute of Mental Health Clinical Antipsychotic Trials of Intervention Effectiveness (CATIE) project: schizophrenia trial design and protocol development.

The National Institute of Mental Health initiated the Clinical Antipsychotic Trials of Intervention Effectiveness (CATIE) program to evaluate the effectiveness of antipsychotic drugs in typical settings and populations so that the study results will be maximally useful in routine clinical situations. The CATIE schizophrenia trial blends features of efficacy studies and large, simple trials to create a pragmatic trial that will provide extensive information about antipsychotic drug effectiveness over at least 18 months. The protocol allows for subjects who receive a study drug that is not effective to receive subsequent treatments within the context of the study. Medication dosages are adjusted within a defined range according to clinical judgment. The primary outcome is all-cause treatment discontinuation because it represents an important clinical endpoint that reflects both clinician and patient judgments about efficacy and tolerability. Secondary outcomes include symptoms, side effects, neurocognitive functioning, and cost-effectiveness. Approximately 50 clinical sites across the United States are seeking to enroll a total of 1,500 persons with schizophrenia. Phase 1 is a double-blinded randomized clinical trial comparing treatment with the second generation antipsychotics olanzapine, quetiapine, risperidone, and ziprasidone to perphenazine, a midpotency first generation antipsychotic. If the initially assigned medication is not effective, subjects may choose one of the following phase 2 trials: (1) randomization to open-label clozapine or a double-blinded second generation drug that was available but not assigned in phase 1; or (2) double-blinded randomization to ziprasidone or another second generation drug that was available but not assigned in phase 1. If the phase 2 study drug is discontinued, subjects may enter phase 3, in which clinicians help subjects select an open-label treatment based on individuals' experiences in phases 1 and 2.

Adolescent↗
PubMed2004

The effect of an empirical trial of high-dose lansoprazole on symptom response of patients with non-cardiac chest pain--a randomized, double-blind, placebo-controlled, crossover trial.

BACKGROUND: Empirical trial with high-dose omeprazole has been shown to be a sensitive tool for diagnosing patients with gastro-oesophageal reflux disease-related non-cardiac chest pain. AIM: To determine the clinical value of an empirical trial of high-dose lansoprazole in detecting patients with gastro-oesophageal reflux disease-related non-cardiac chest pain. METHODS: Patients who were referred by a cardiologist after a comprehensive evaluation, with at least three episodes per week of unexplained chest pain as the predominant symptom, were enrolled into the study. Oesophageal mucosal disease was determined by upper endoscopy followed by 24-h oesophageal pH monitoring to assess acid exposure. Patients were then randomized to either placebo or lansoprazole 60 mg am and 30 mg pm for 7 days. After a washout period of 1 week, patients crossed over to the other arm of the study for an additional 7 days. Patients completed a daily diary assessing severity and frequency of chest pain as the predominant symptom throughout the baseline treatment and washout periods. The lansoprazole empirical trial was considered diagnostic if chest pain score improved > or =50% than baseline. RESULTS: Of the 40 patients with non-cardiac chest pain that were enrolled, 18 (45%) had erosive oesophagitis and/or abnormal pH test (gastro-oesophageal reflux disease-positive) and 22 (55%) had both tests negative (gastro-oesophageal reflux disease-negative). Of the gastro-oesophageal reflux disease-positive patients, 14 (78%) had significantly higher symptom improvement on lansoprazole than on placebo (22%) (P = 0.0143). Of the gastro-oesophageal reflux disease-negative group, two (9.1%) markedly improved on the medication and eight (36.3%) on placebo (P = 0.75). The sensitivity and specificity of the lansoprazole empirical trial was 78 and 80%, respectively. By day 2, 12 (85.7%) of the gastro-oesophageal reflux disease-related non-cardiac chest pain responders had either complete or almost complete symptom resolution. CONCLUSIONS: The lansoprazole empirical trial is highly sensitive and specific for diagnosing gastro-oesophageal reflux disease-related non-cardiac chest pain patients. The trial enables diagnosing most of the responders within the first 2 days and thus a shorter duration of therapy may be considered in a subset of non-cardiac chest pain patients.

2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed2000

The impact of metrifonate therapy on caregivers of patients with Alzheimer's disease: results from the MALT clinical trial. Metrifonate in Alzheimer's Disease Trial.

OBJECTIVE: To assess the impact on burden reported by caregivers of patients with mild to moderate Alzheimer's disease (AD) who were treated with metrifonate during a randomized double blind clinical trial. DESIGN: Randomized clinical trial, with a 2-week screening period and a 26-week double blind, placebo controlled, treatment phase. Caregivers were assessed at baseline, at 12 weeks, and at end of trial. SETTING: Caregivers were interviewed at clinics as part of the assessment of the patients. PARTICIPANTS: Six hundred and three caregivers of AD patients who were enrolled in the MALT trial; 591 (98%) provided data suitable for analysis at baseline, and 546 (91%) provided data allowing for inclusion in the analysis of change scores. MEASUREMENTS: The Caregiver Burden Assessment consisted of the Screen for Caregiver Burden, including both subjective (SCB-subj) and objective (SCB-obj) scores; the cognitive subscale of Poulshock and Deimling (PD); an abridged version of the Relatives Stress Scale (aRSS); assessments of time spent in providing care, including the Caregiver Activity Time Scale (CATS); and demographic and background variables on both the patient and caregiver. RESULTS: Treatment of mild to moderate AD patients with metrifonate for a duration of 26 weeks significantly reduced the psychological burden of care to the caregivers, as measured by the SCB-subj, the PD, and the aRSS. There were no statistically significant differences on the measures assessing the time spent in caregiving, except for the caregiver's subjective impression of the change in time spent providing care during the trial. When comparing individual dose groups, most of the measures of burden showed the largest benefits in burden for the 60/80 mg group, followed by the 40/50 mg group, and then the placebo group. However, there was no statistically significant dose effect. CONCLUSIONS: This study provides the first evidence from a randomized clinical trial of any acetylcholinesterase inhibitor used in the treatment of AD demonstrating a positive impact on the patient's caregiver as well as benefits to the patient. These results were shown consistently across several measurement scales and were observed after six months of treatment. These findings reinforce the clinical significance of research that has shown that metrifonate has beneficial impacts on the cognitive, behavioral, and functional abilities of AD patients. Because caregiver burden is a leading factor in the decision for institutional care placement, the ability to favorably impact that burden through pharmacological treatment of the patient is important.

Aged↗
PubMedDate not supplied

The diabetes control and complications trial (DCCT): the trial coordinator perspective. Report by the DCCT Research Group.

We present an overview of the role of the trial coordinator in the Diabetes Control and Complications Trial (DCCT). The DCCT is a multicenter clinical trial designed to examine the effects of two different diabetes treatment regimens on the appearance and progression of the early vascular complications of IDDM. Although the specific responsibilities assumed by the trial coordinators differ from center to center, in general they include administration, recruitment, eligibility testing, and patient management. The trial coordinator's role has evolved with the needs of the DCCT, and may serve as a model for other large multicenter trials.

Administrative Personnel↗
PubMed2005

Design issues of randomized phase II trials and a proposal for phase II screening trials.

Future progress in improving cancer therapy can be expedited by better prioritization of new treatments for phase III evaluation. Historically, phase II trials have been key components in the prioritization process. There has been a long-standing interest in using phase II trials with randomization against a standard-treatment control arm or an additional experimental arm to provide greater assurance than afforded by comparison to historic controls that the new agent or regimen is promising and warrants further evaluation. Relevant trial designs that have been developed and utilized include phase II selection designs, randomized phase II designs that include a reference standard-treatment control arm, and phase II/III designs. We present our own explorations into the possibilities of developing "phase II screening trials," in which preliminary and nondefinitive randomized comparisons of experimental regimens to standard treatments are made (preferably using an intermediate end point) by carefully adjusting the false-positive error rates (alpha or type I error) and false-negative error rates (beta or type II error), so that the targeted treatment benefit may be appropriate while the sample size remains restricted. If the ability to conduct a definitive phase III trial can be protected, and if investigators feel that by judicious choice of false-positive probability and false-negative probability and magnitude of targeted treatment effect they can appropriately balance the conflicting demands of screening out useless regimens versus reliably detecting useful ones, the phase II screening trial design may be appropriate to apply.

Clinical Trials, Phase II as Topic↗
PubMed2003

Including a 'no active intervention' arm in surgical trials is possible: evidence from the CLasP randomised trial.

OBJECTIVES: To examine the impact of including a 'no active intervention' arm (called 'conservative management') in a randomised controlled trial comparing treatments (including surgery) for men with lower urinary tract symptoms related to benign prostatic enlargement. METHODS: Outcomes 7.5 months after randomisation were acceptability of randomisation, overall acceptability of and satisfaction with conservative management, impact on quality of life, perceived need for further treatment and treatment failure (defined a priori). RESULTS: In total, 177 (out of 755) patients refused randomisation, including 31% who did not want surgery and 22% who wanted surgery. Most men randomised to conservative management were willing to undertake it as part of a trial but at the end of the trial they were divided between those who wanted to continue with it and those who expected surgery. At follow-up, 39% of conservative management patients requested surgery, and interference of symptoms with life and an unsuccessful outcome were more commonly reported in this arm. There were no appreciable differences between treatment groups in terms of treatment failures. CONCLUSIONS: Including a 'no active intervention' arm did not appear to have a detrimental effect on patient recruitment or the completion of this trial in the short-term; overall, conservative management was successfully completed by the majority of patients during the trial period, suggesting that researchers need not avoid including a no-intervention arm in surgical trials as long as they take care with its presentation.

Aged↗
PubMed1993

The ABCD (Appropriate Blood Pressure Control in Diabetes) trial. Rationale and design of a trial of hypertension control (moderate or intensive) in type II diabetes.

OBJECTIVE: The primary objective of the ABCD (Appropriate Blood Pressure Control in Diabetes) Trial is to determine the efficacy of intensive versus moderate antihypertensive control on the outcome of type II diabetic end-organ complications in normotensive and hypertensive populations. The secondary objective is to determine whether any differential effect on end-organ complications exists between an angiotensin converting enzyme inhibitor (enalapril) and a calcium channel blocker (nisoldipine). DESIGN: The ABCD Trial is a prospective, controlled, randomized, double-blind trial, with a planned follow-up of 5 years. SETTING: All patients are seen at the Colorado Prevention Center, site of the ABCD Trial, for follow-up visits. PATIENTS: Patients are type II diabetic males and females between the ages of 40 and 74 years with entry diastolic blood pressures > or = 80 mmHg. Patients were recruited from University of Colorado-affiliated hospitals, several health maintenance organizations, and mailing lists from the Colorado affiliate of the American Diabetes Association. INTERVENTIONS: Patients were randomized to intensive antihypertensive drug therapy or moderate antihypertensive drug therapy. Patients were also randomized to nisoldipine or enalapril, with open-label medications added if further blood pressure control was necessary. MAIN OUTCOME MEASURES: The primary outcome measure is glomerular filtration rate as assessed by 24-hour creatinine clearance. Secondary outcome measures are microalbumin urinary excretion, left ventricular hypertrophy, retinopathy, and neuropathy. Cardiovascular morbidity and mortality will also be evaluated. CONCLUSION: Given the data showing the impact of hypertension on diabetic complications, the ABCD Trial was designed to determine if intensive antihypertensive therapy will be more efficacious than moderate antihypertensive therapy on the outcome of these complications. Results from the ABCD Trial are expected to lend interpretable and clinically relevant findings with regards to the treatment of hypertension in type II diabetes.

Adult↗