Layout 1 ISDS Annual Conference Proceedings 2012. This is an Open Access article distributed under the terms of the Creative Commons Attribution- Noncommercial 3.0 Unported License (http://creativecommons.org/licenses/by-nc/3.0/), permitting all non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. ISDS 2012 Conference Abstracts Risk of Cardiovascular Morbidity and Mortality in Relation to Temperature Robert Mathes*, Kazuhiko Ito and Thomas Matte New York City Department of Health and Mental Hygiene, Queens, NY, USA Objective To examine the effects of temperature on cardiovascular-related (CVD) morbidity and mortality among New York City (NYC) resi- dents. Introduction Extreme temperatures are consistently shown to have an effect on CVD-related mortality [1, 2]. A large multi-city study of mortality demonstrated a cold-day and hot-day weather effect on CVD-related deaths, with the larger impact occurring on the coldest days [3]. In contrast, the association between weather and CVD-related morbid- ity is less clear [4, 5]. The purpose of this study is to characterize the effect of temperature on CVD-related emergency department (ED) visits, hospitalizations, and mortality on a large, heterogeneous pop- ulation. Additionally, we conducted a sensitivity analysis to deter- mine the impact of air pollutants, specifically fine particulates (PM2.5) and ozone (O3), along with temperature, on CVD outcomes. Methods We analyzed daily weather conditions, ED visits classified as CVD-related based on chief complaint text, hospitalizations, and nat- ural cause deaths that occurred in NYC between 2002 and 2006. ED visits were obtained from data reported daily to the city health de- partment for syndromic surveillance. Inpatient admissions were ob- tained from the Statewide Planning and Research Cooperative System, a data reporting system developed by New York State. Mor- tality data were obtained from the NYC Office of Vital Statistics. Data for PM2.5 and O3 were obtained from all available air quality monitors within the five boroughs of NYC. To estimate risk of CVD morbidity and mortality, we used generalized linear models using a Poisson distribution to calculate relative risks (RR) and 95% confi- dence intervals (CI). A non-linear distributed lag was used to model mean temperature in order to allow for its effect on the same day and on subsequent days. Models were fit separately for cold season (Oc- tober through March) and warm season (April through September) given season may modify the effect on CVD outcomes. For our sen- sitivity analysis, we included PM2.5 and O3 in our model. Results During the cold season, CVD-related ED visits and hospitaliza- tions increased, while mortality decreased, with increasing mean tem- perature on the same day and lagged days. Extremely cold temperature was associated with a small increase of same day in-hos- pital mortality though generally cold temperatures did not appear to be associated with higher mortality. The opposite was observed in the warm season as ED visits and hospitalizations decreased, and mortality increased, with increasing mean temperature on the same day and on lagged days. Our sensitivity analysis, in which we con- trolled for PM2.5 and O3, demonstrated little effect of these air pol- lutants on the relationship between temperature and CVD outcomes. Conclusions Our results suggest a decline in risk of a CVD-related ED visit and hospitalization during extreme temperatures on the same day and on recent day lags for both cold and warm seasons. In contrast, our find- ings for mortality indicate an increase in risk of CVD-related deaths during hot temperatures. No mortality effect was observed during cold temperatures. The effects of extreme temperatures on CVD-re- lated morbidity may be explained by behavioral patterns, as people are more likely to stay indoors on the coldest and hottest days. Keywords Morbidity; Mortality; Cardiovascular; Temperature Acknowledgments This research was funded by the Environmental Protection Agency, STAR Grant R833623010, and in conjunction with the Alfred P. Sloan Founda- tion, grant 2010-12-14. We thank the members of the New York City De- partment of Health and Mental Hygiene Syndromic Surveillance Unit. References 1. Basu, R. and B.D. Ostro, A multicounty analysis identifying the pop- ulations vulnerable to mortality associated with high ambient tem- perature in California. Am J Epidemiol, 2008. 168(6): p. 632-7. 2. Braga, A.L., A. Zanobetti, and J. Schwartz, The effect of weather on respiratory and cardiovascular deaths in 12 U.S. cities. Environ Health Perspect, 2002. 110(9): p. 859-63. 3. Medina-Ramon, M. and J. Schwartz, Temperature, temperature ex- tremes, and mortality: a study of acclimatisation and effect modifica- tion in 50 US cities. Occup Environ Med, 2007. 64(12): p. 827-33. 4. Josseran, L., et al., Syndromic surveillance and heat wave morbidity: a pilot study based on emergency departments in France. BMC Med Inform Decis Mak, 2009. 9: p. 14. 5. Knowlton, K., et al., The 2006 California heat wave: impacts on hos- pitalizations and emergency department visits. Environ Health Per- spect, 2009. 117(1): p. 61-7. *Robert Mathes E-mail: rmathes@health.nyc.gov Online Journal of Public Health Informatics * ISSN 1947-2579 * http://ojphi.org * 5(1):e144, 2013