JM Gohlke, BF Zaitchik, S Kent, TT Smith, LA McClure

1. Preterm birth and non-accidental mortality during heat waves: Trends in urban and rural settings in the Deep South JM Gohlke, BF Zaitchik, S Kent, TT Smith, LA McClure October 30, 2013

2. Adverse health outcomes during heat waves • Previous research indicates non-accidental mortality increases during heat waves in cities (Anderson and Bell 2011; Peng et al. 2011). • Basu et al. 2011 reported an increased risk of preterm birth during heat waves in California. • Previously identified important covariates include SES, age chronic disease status, minority status, and geography (greater risk in northern ‘less hot’ cities). • A variety of heat wave definitions exist. • Risk in rural settings have not been evaluated.

3. Rural Health Challenges Compared with their urban counterparts, residents of rural areas: • Report fair or poor health. • More often have chronic conditions such as diabetes. • Die from heart disease. Rural residents have fewer visits to health care providers and are less likely to receive recommended preventive services. Rural minorities appear to be particularly disadvantaged, and differences are observed in cancer screening, management of cardiovascular disease and diabetes, and mental health.

4. Adult Admissions for Uncontrolled Diabetes per 100,000 Population, by Race Source: Healthcare Cost and Utilization Project, State Inpatient Databases disparities analysis file, 2001.Key: Metropolitan = 50,000 or more inhabitants; micropolitan = 10,000 to 50,000 inhabitants; noncore = not metropolitan or micropolitan.

5. Heat-related illnesses and rurality • 33 of 55 rural Alabama counties do not provide labor & delivery service ADPH, 2012

6. Alabama birth and death record analysis (1990-2010) Time-stratified case-crossover design Responses: • Non-accidental mortality (N=298,879) • Preterm Birth (N=281,546) Exposure metric: North American Land Data Assimilation System (NLDAS), NASA

7. Sixteen definitions for a heat wave Smith et al. 2013 Climatic Change

8. Average number of hw days 1979-2011 average number of HW days b. a. c. d. f. e. g. h. i. j. l. k. o. n. m. Smith et al. 2012 Climatic Change

9. Temporal Trends: HWs in the SE have increased at 2X the rate of HWs in the NE Smith et al. 2012 Climatic Change

10. Number of AL zip-code level avg. heat wave index days per year A=HI02 B=HI07 C=HI12 D=HI15 Kent et al. 2013 Submitted

11. Percent increase in PTB and NAD on a heat wave day

12. Lags, duration of heatwave A=HI02 B=HI07 C=HI12 D=HI15

13. A dose-response relationship is evident

14. Are the HIs actually different? Bootstrapped confidence intervals

15. Is the effect modified by rurality? Kent et al. 2013 BMC Pregnancy and Childbirth

16. Spatial distributions of A: percent poverty and B: percent AA Kent et al. 2013 BMC Pregnancy and Childbirth

17. Spatial distributions of A: preterm birth and B: low birth weight Kent et al. 2013 BMC Pregnancy and Childbirth

18. Area level poverty is associated with increased PTB and low birth weight Kent et al. 2013 BMC Pregnancy and Childbirth

19. PTB rates have been declining, LBW is still increasing in most isolated rural areas Kent et al. 2013 BMC Pregnancy and Childbirth

20. Are PTB effects of heat waves modified by rurality? Kent et al. 2013 Submitted

21. Are NAD effects of heat waves modified by rurality? Kent et al. 2013 Submitted

22. Conclusions • Use of satellite-derived datasets allows for consistent exposure estimation in urban and rural areas. • Analysis of birth and death records in Alabama suggests risk of premature birth is heightened during heat waves. • The current heat wave definition may be improved through use of relative daily mean temperatures.

23. Acknowledgements UAB SOPH • Shia Kent • Molly Bernhard • Mary Evans • Leslie McClure JHU, Dept. of Earth and Planetary Sciences • Tiffany Smith • Ben Zaitchik The National Institute of Environmental Health Sciences Grant R21 ES020205