Heat stress and sudden infant death syndrome incidence: a United States population epidemiologic study.
OBJECTIVE
To determine the role of heat stress in sudden infant death syndrome (SIDS) by examining the SIDS rates during periods of extreme environmental temperatures in a period when most infants were placed prone for sleep.


METHODS
A retrospective study of SIDS rates and mortality rates attributable to excessive environmental heat in relationship to climatologic temperature was performed. Data were collected for each of 454 counties in 4 states (Arkansas, Georgia, Kansas, and Missouri) from May 1 to September 30, 1980, and were then summed to yield the mortality rates for each 5 degrees F (2.8 degrees C) temperature range.


RESULTS
chi2 analyses revealed significant relationships for heat-related mortality rates and both the maximal daily temperature and mean daily temperature but demonstrated no such relationships for SIDS rates. No association between SIDS rates and heat-related mortality rates was found with Spearman's ranked correlation, for either the maximal daily temperature or the mean daily temperature.


CONCLUSIONS
On the basis of our findings of no significant association between SIDS and either measure of temperature during periods of high heat stress-related death rates, it seems unlikely that the heat stress associated with the combination of prone sleep positions and elevated environmental temperatures has a significant role in the development of SIDS.
Scheers-Masters
Joshua R
JR
Edward Mallinckrodt Department of Pediatrics, Washington University School of Medicine, St Louis, Missouri 63110, USA.
Schootman
Mario
M
Thach
Bradley T
BT
D016009:Chi-Square Distribution; D018882:Heat Stress Disorders / Q000150:complications / Q000401:mortality*; D006358:Hot Temperature / Q000009:adverse effects*; D006801:Humans; D015994:Incidence; D007223:Infant; D016684:Prone Position; D012189:Retrospective Studies; D013398:Sudden Infant Death / Q000453:epidemiology* / Q000209:etiology; D014481:United States / Q000453:epidemiology