Minimizing Attrition for Multisite Emergency Care Research

Loss to follow-up of enrolled patients (a.k.a. attrition) is a major threat to study validity and power. Minimizing attrition can be challenging even under ideal research conditions, including the presence of adequate funding, experienced study personnel, and a refined research infrastructure. Emergency care research is shifting toward enrollment through multisite networks, but there have been limited descriptions of approaches to minimize attrition for these multicenter emergency care studies. This concept paper describes a stepwise approach to minimize attrition, using a case example of a multisite emergency department prospective cohort of over 3,000 patients that has achieved a 30-day direct phone follow-up attrition rate of <3%. The seven areas of approach to minimize attrition in this study focused on patient selection, baseline contact data collection, patient incentives, patient tracking, central phone banks, local enrollment site assistance, and continuous performance monitoring. Appropriate study design, including consideration of these methods to reduce attrition, will be time well spent and may improve study validity

Comparison of 30-Day Serious Adverse Clinical Events for Elderly Patients Presenting to the Emergency Department With Near-Syncope Versus Syncope

Study objectiveControversy remains in regard to the risk of adverse events for patients presenting with syncope compared with near-syncope. The purpose of our study is to describe the difference in outcomes between these groups in a large multicenter cohort of older emergency department (ED) patients.MethodsFrom April 28, 2013, to September 21, 2016, we conducted a prospective, observational study across 11 EDs in adults (≥60 years) with syncope or near-syncope. A standardized data extraction tool was used to collect information during their index visit and at 30-day follow-up. Our primary outcome was the incidence of 30-day death or serious clinical events. Data were analyzed with descriptive statistics and multivariate logistic regression analysis adjusting for relevant demographic or historical variables.ResultsA total of 3,581 patients (mean age 72.8 years; 51.6% men) were enrolled in the study. There were 1,380 patients (39%) presenting with near-syncope and 2,201 (61%) presenting with syncope. Baseline characteristics revealed a greater incidence of congestive heart failure, coronary artery disease, previous arrhythmia, nonwhite race, and presenting dyspnea in the near-syncope compared with syncope cohort. There were no differences in the primary outcome between the groups (near-syncope 18.7% versus syncope 18.2%). A multivariate logistic regression analysis identified no difference in 30-day serious outcomes for patients with near-syncope (odds ratio 0.94; 95% confidence interval 0.78 to 1.14) compared with syncope.ConclusionNear-syncope confers risk to patients similar to that of syncope for the composite outcome of 30-day death or serious clinical event

Recurrent syncope is not an independent risk predictor for future syncopal events or adverse outcomes

Almost 20% of patients with syncope will experience another event. It is unknown whether recurrent syncope is a marker for a higher or lower risk etiology of syncope. The goal of this study is to determine whether older adults with recurrent syncope have a higher likelihood of 30-day serious clinical events than patients experiencing their first episode.MethodsThis study is a pre-specified secondary analysis of a multicenter prospective, observational study conducted at 11 emergency departments in the US. Adults 60 years or older who presented with syncope or near syncope were enrolled. The primary outcome was occurrence of 30-day serious outcome. The secondary outcome was 30-day serious cardiac arrhythmia. In multivariate analysis, we assessed whether prior syncope was an independent predictor of 30-day serious events.ResultsThe study cohort included 3580 patients: 1281 (35.8%) had prior syncope and 2299 (64.2%) were presenting with first episode of syncope. 498 (13.9%) patients had 1 prior episode while 771 (21.5%) had >1 prior episode. Those with recurrent syncope were more likely to have congestive heart failure, coronary artery disease, previous diagnosis of arrhythmia, and an abnormal ECG. Overall, 657 (18.4%) of the cohort had a serious outcome by 30 days after index ED visit. In multivariate analysis, we found no significant difference in risk of events (adjusted odds ratio 1.09; 95% confidence interval 0.90-1.31; p = 0.387).ConclusionIn older adults with syncope, a prior history of syncope within the year does not increase the risk for serious 30-day events