Excess mortality during heat waves and cold spells in Moscow, Russia.
OBJECTIVE
To estimate excess mortality during heat waves and cold spells, and to identify vulnerable population groups by age and cause of death.


METHODS
Daily mortality in Moscow, Russia from all non-accidental, cardiovascular and respiratory causes between January 2000 and February 2006 was analysed. Mortality and displaced mortality during cold spells and heat waves were estimated using independent samples t tests.


RESULTS
Cumulative excess non-accidental mortality during the 2001 heat wave was 33% (95% CI 20% to 46%), or approximately 1200 additional deaths, with short-term displaced mortality contributing about 10% of these. Mortality from coronary heart disease increased by 32% (95% CI 16% to 48%), cerebrovascular mortality by 51% (95% CI 29% to 73%) and respiratory mortality by 80% (95% CI 57% to 101%). In the 75+ age group, corresponding mortality increments were consistently higher except respiratory deaths. An estimated 560 extra deaths were observed during the three heat waves of 2002, when non-accidental mortality increased by 8.5%, 7.8% and 6.1%, respectively. About 40% of these deaths were brought forward by only a few days, bringing net mortality change down to 3.2% (95% CI 0.8% to 5.5%). The cumulative effects of the two cold spells in 2006 on mortality were significant only in the 75+ age group, for which average daily mortality from all non-accidental causes increased by 9.9% (95% CI 8.0% to 12%) and 8.9% (95% CI 6.7% to 11%), resulting in 370 extra deaths; there were also significant increases in coronary disease mortality and cerebrovascular mortality.


CONCLUSIONS
This study confirms that daily mortality in Moscow increases during heat waves and cold spells. A considerable proportion of excess deaths during heat waves occur a short time earlier than they would otherwise have done. Harvesting, or short-term mortality displacement, may be less significant for longer periods of sustained heat stress.
Revich
B
B
Institute of Forecasting, Nakhimovsky Prospect 47, Moscow 117418, Russia.
Shaposhnikov
D
D
D000293:Adolescent; D000328:Adult; D000368:Aged; D002423:Cause of Death; D002648:Child; D002675:Child, Preschool; D003081:Cold Climate / Q000009:adverse effects*; D006358:Hot Temperature / Q000009:adverse effects*; D006801:Humans; D007223:Infant; D008875:Middle Aged; D009031:Moscow / Q000453:epidemiology; D012621:Seasons; D055815:Young Adult