Testing Strategies and Poor Outcomes of Syncope among Medicare Beneficiaries

Background: Syncope is a common problem among older patients in the United States and national guidelines recommend a variety of tests to determine the etiology. However, few data are available regarding how tests are used nationwide and outcomes of patients presenting with syncope. Methods: Using the nationally representative 5% sample of Medicare beneficiaries 65 years or older, we identified patients who had at least 1 inpatient or 2 outpatient claims for syncope between 2001 and 2010. We excluded beneficiaries with a pacemaker or implantable cardioverter defibrillator in situ prior to the incident syncope encounter that required no prior claim of syncope in the prior 365 days. Results: The overall incidence of syncope in 2001 was 11.8 per 1000 person years and remained stable over time ranging from 10.3 to 14.6 per 1000 person years. The average age of beneficiaries with syncope was 79, with the majority being women (63.3%) and white (87.5%). Hypertension was the most common comorbid condition (84%) followed by coronary heart disease (46.5%). When considering the tests ordered within 90 days of the incident encounter, the most frequently ordered tests were CT head (57%) and echocardiogram (50%). Holter monitors were ordered for 18% of beneficiaries, implantable loop recorders for 0.2%, tilt table testing for 4% and electrophysiology study for 2.7% of beneficiaries. From 2001 to 2010, the frequency of these tests did not significantly vary. Mortality at one year was 13% overall (17% for inpatients and 6% for outpatients). All cause readmission at one year was 44% with readmissions for syncope 9% (figure). Conclusion: Syncope is a common condition and is associated with a high mortality and hospitalization within 1 year of initial presentation. Guideline recommended diagnostic tests are ordered infrequently and represent an opportunity to improve care by developing a structured approach for the evaluation of syncope.