Heat Waves and Cold Spells and Their Effect on Mortality: An Analysis of Micro-Data for the Netherlands In the Nineteenth and Twentieth Century

Peter Ekamper, Netherlands Interdisciplinary Demographic Institute (NIDI)
Frans W.A. van Poppel, Netherlands Interdisciplinary Demographic Institute (NIDI)
Coen van Duin, Statistics Netherlands
Kees Mandemakers, Erasmus University Rotterdam

To gain insight into the changing impact of cold and heat on mortality, we analyze Dutch individual death records in relation to daily temperature for the period 1855-1950 for three Dutch provinces. Using negative binomial regression models we studied whether the effect of extreme heat and cold varied by province, age, sex, and social class and analyze the changes in the vulnerability to temperature fluctuations. Our study showed that between 1855 and 1950 total mortality underwent an immediate increase when temperature increased above the optimal value. We observed increases in mortality related to increases in temperature 1-2 days before the day of death, and strong delayed effects for lag-days 7-14 and 15-30. The immediate and delayed effects of heat were strongest for infants and unskilled workers, but their vulnerability to heat declined after 1930. Short-term delayed effects of heat and longer-term delayed effects declined from 1900 or 1930 on.