Abstract 19298: Is the Seasonal Variation in Acute Aortic Dissection Occurrence Associated with Flu Activity?
Introduction: Numerous reports have described seasonal patterns of acute aortic dissection (AAD), but reasons for such patterns are unknown. Correlations between cardiovascular morbidity and seasonal influenza have also been described.
Methods: We compared monthly admissions for AADs at our institution to the US seasonal influenza activity based on US Centers for Disease Control statistics over 13 years. Seasonal variation was modeled by autoregressive integrated moving average (ARIMA) analysis, and multivariate effects of season and influenza activity on aortic dissection admissions were assessed by response surface regression.
Results: From January 2001 to December 2013, we treated 869 patients with AAD (398 type A, 442 typical type B, 29 type B variants). Admissions for AAD were identified as highest during the months of November to March (high period-HP). For type A AAD, 3.1 cases per month were admitted during HP, compared to 2.1 cases per month for the remainder of the year (p<0.002). Type B AADs averaged 3.2 cases/month during the HP compared to 2.9 cases/month for the remainder of the year (p=0.40). Influenza activity averaged 2.6% during HP compared to 1.1% in the remaining months (p<0.0001). ARIMA models for AAD over the entire 156 month observation period showed statistically significant seasonality (p<0.0001), and smoothed spline plots showed type A dissection and flu activity moving cyclically and generally in synchrony throughout the period (fig 1). Response surface regression demonstrated significant effects of flu activity (p<0.034) and month of the year (p<0.048) on the rate of AAD occurrence at our center.
Conclusion: Presentation of AAD to our center and seasonal influenza activity in the US were both elevated during the HP, and were significantly correlated. Type A AAD significantly correlated with season or flu activity while Type B did not. Seasonal flu vaccination among high risk patients may be appropriate
Author Disclosures: H.K. Sandhu: None. K.M. Charlton-Ouw: None. S.S. Leake: None. A. Azizzadeh: Consultant/Advisory Board; Modest; Gore Associates, Medtronic. T.C. Nguyen: None. A.L. Estrera: None. H.J. Safi: None. C.C. Miller: None.
- © 2014 by American Heart Association, Inc.