Abstract MP11: Association of Sick Sinus Syndrome with Incident Cardiovascular Disease and Mortality: the Atherosclerosis Risk in Communities Study and Cardiovascular Health Study
Background: Sick sinus syndrome (SSS) is a disorder characterized by symptomatic dysfunction of the sinoatrial node. Despite being relatively frequent and a major indication for pacemaker implantation (PMI), the impact of SSS on the risk of other cardiovascular diseases (CVD) and mortality is unclear. Thus, we assessed whether SSS incidence was associated with mortality and CVD in two community-based studies.
Methods: We included 19,893 men and women age 45 and older enrolled in the Atherosclerosis Risk in Communities (ARIC) study and the Cardiovascular Health Study (CHS), without pacemaker and free of atrial fibrillation (AF) at baseline. Incident cases of SSS were adjudicated after review of medical charts from hospitalizations with a 427.81 ICD-9 code. Ascertainment of incident CVD (heart failure, myocardial infarction, stroke, AF, PMI) and mortality was done according to standard validated protocols. The association between SSS and the selected outcomes was assessed using age, sex, and race-standardized rates and multivariable Cox models adjusted for potential confounders.
Results: During a mean follow-up of 17 years, 213 incident SSS events were identified and validated (incidence = 6 events per 10,000 person-years). Age, sex, and race-standardized rates for each of the outcomes in those with and without SSS are presented in the Table. Overall, individuals with SSS had higher rates of mortality and CVD. These differences were still present, though weakened, after adjustment for baseline cardiovascular risk factors (Table, Model 2). After additional adjustment for incident CVD (Model 3), SSS was no longer associated with higher mortality, myocardial infarction or stroke, but an association with heart failure, AF and PMI remained.
Conclusion: Individuals who develop SSS are at increased risk of death and incident CVD. Their management should incorporate comprehensive cardiovascular prevention in addition to symptom relief. The mechanisms underlying these associations warrant further investigation.
Author Disclosures: A. Alonso: None. P.N. Jensen: None. F.L. Lopez: None. L.Y. Chen: None. B.M. Psaty: None. A.R. Folsom: None. S.R. Heckbert: None.
This research has received full or partial funding support from the American Heart Association, National Center.
- © 2014 by American Heart Association, Inc.