Citations

Background: In CREST2, intensive medical management of subjects’ vascular risk factors is overseen by the site Principal Investigator (PI) and implemented by a designated Medical Management Physician (MMP) and coordinator. These physicians have different specialties and experience with risk factor management. We sought to determine the relationship between risk factor control and PI and MMP specialty. Methods: Data on 613 patients with at least 1 follow-up visit from 105 CREST2 sites were used for these analyses. CREST2 sites were categorized based on both PI specialty and MMP specialty. Specialty of the site-designated primary MMP was used for sites with more than one MMP. We compared the percentage of patients in target at last follow-up visit for the primary risk factors, LDL < 70 mg/dL and SBP <140 mm Hg, among PI specialties and MMP specialties, using the chi-square test. Results: The table shows the number of patients by PI and MMP specialty, as well as their control of SBP and LDL. There were no significant differences in control of SBP or LDL by PI specialty. There was a trend toward an association between LDL control and MMP specialty, with higher rates of LDL control at sites with Internal Medicine MMP specialists and lower rates of control with Vascular Surgery MMPs. SBP control rates were not significantly different across MMP specialties. Conclusions: In this early analysis of risk factor control in the CREST2 study, site PI and MMP specialty did not have a significant effect on LDL and SBP during follow-up. This suggests that protocol care pathways are generalizable to diverse physicians.

Background and Purpose— Multicenter clinical trials attempt to select sites that can move rapidly to randomization and enroll sufficient numbers of patients. However, there are few assessments of the success of site selection. Methods— In the CREST-2 (Carotid Revascularization and Medical Management for Asymptomatic Carotid Stenosis Trials), we assess factors associated with the time between site selection and authorization to randomize, the time between authorization to randomize and the first randomization, and the average number of randomizations per site per month. Potential factors included characteristics of the site, specialty of the principal investigator, and site type. Results— For 147 sites, the median time between site selection to authorization to randomize was 9.9 months (interquartile range, 7.7, 12.4), and factors associated with early site activation were not identified. The median time between authorization to randomize and a randomization was 4.6 months (interquartile range, 2.6, 10.5). Sites with authorization to randomize in only the carotid endarterectomy study were slower to randomize, and other factors examined were not significantly associated with time-to-randomization. The recruitment rate was 0.26 (95% confidence interval, 0.23–0.28) patients per site per month. By univariate analysis, factors associated with faster recruitment were authorization to randomize in both trials, principal investigator specialties of interventional radiology and cardiology, pre-trial reported performance >50 carotid angioplasty and stenting procedures per year, status in the top half of recruitment in the CREST trial, and classification as a private health facility. Participation in StrokeNet was associated with slower recruitment as compared with the non-StrokeNet sites. Conclusions— Overall, selection of sites with high enrollment rates will likely require customization to align the sites selected to the factor under study in the trial. Clinical Trial Registration— URL: http://www.clinicaltrials.gov . Unique identifier: NCT02089217.

Rationale Trials conducted decades ago demonstrated that carotid endarterectomy by skilled surgeons reduced stroke risk in asymptomatic patients. Developments in carotid stenting and improvements in medical prevention of stroke caused by atherothrombotic disease challenge understanding of the benefits of revascularization. Aim Carotid Revascularization and Medical Management for Asymptomatic Carotid Stenosis Trial (CREST-2) will test whether carotid endarterectomy or carotid stenting plus contemporary intensive medical therapy is superior to intensive medical therapy alone in the primary prevention of stroke in patients with high-grade asymptomatic carotid stenosis. Methods and design CREST-2 is two multicenter randomized trials of revascularization plus intensive medical therapy versus intensive medical therapy alone. One trial randomizes patients to carotid endarterectomy plus intensive medical therapy versus intensive medical therapy alone; the other, to carotid stenting plus intensive medical therapy versus intensive medical therapy alone. The risk factor targets of centrally directed intensive medical therapy are LDL cholesterol <70 mg/dl and systolic blood pressure <140 mmHg. Study outcomes The primary outcome is the composite of stroke and death within 44 days following randomization and stroke ipsilateral to the target vessel thereafter, up to four years. Change in cognition and differences in major and minor stroke are secondary outcomes. Sample size Enrollment of 1240 patients in each trial provides 85% power to detect a treatment difference if the event rate in the intensive medical therapy alone arm is 4.8% higher or 2.8% lower than an anticipated 3.6% rate in the revascularization arm. Discussion Management of asymptomatic carotid stenosis requires contemporary randomized trials to address whether carotid endarterectomy or carotid stenting plus intensive medical therapy is superior in preventing stroke beyond intensive medical therapy alone. Whether carotid endarterectomy or carotid stenting has favorable effects on cognition will also be tested. Trial registration United States National Institutes of Health Clinicaltrials.gov NCT02089217