Human Health Effects of  Climate Change:
The Evidence
&
 The Knowledge Gaps

Francesca Dominici
 NCAR October 26 2007
Potential Climate Change Impacts
Slide 3
Insect-, Tick-, and Rodent-Borne Diseases
Changes in weather and vegetation can affect the habitats of organisms such as mosquitoes, rats, and their parasites.
Ex. Malaria
Right now: about 45% of the worldÕs population lives in the zone for malaria transmission. Could rise to 60%

Water-Borne Diseases
Heavy rainfall and runoff can damage water quality
Higher risk from bacteria and infectious viruses
Especially problematic for combined wastewater systems

Climate change impact on biogenic emissions
Higher temperatures cause increased VOC emissions from trees
Increase of 10¡C can double biogenic emissions
Biogenic emissions can be on the same order of magnitude as anthropogenic emissions

Temperature and Health
"Temperature-Related Deaths"
Temperature-Related Deaths

Slide 9
Not Just Warming

More Extreme Events

Flooding
heatwaves
Etc.
Slide 11
Heat Wave in Europe
Prospective study in an university hospital in Lyon following the French heat wave (August 1-20,2003)
A total of 83 patients presented with heatstroke
28-day and 2 years mortality rates were 58% and 71% respectively
14800 heat stroke deaths in France

 Public health interventions
Worse outcomes were derived in setting in which the hospital and the community were not prepared for heat related illness, a situation that is probably similar to most communities in temperate climates
Innovative ways to treat heatstroke (public health interventions)
Identifying individuals at higher risk of heat strokes (susceptibility)

Temperature, Air Pollution, and Health
Air Pollution Effects
Climate changes could affect air pollution levels
Precipitation, wind speed and direction, temperature
Higher temperature means
Faster chemical reaction rates for formation of tropospheric ozone
More emissions of natural ozone precursors

Slide 16
Slide 17
Ozone Chemical Reaction Rates Increases with Temperature
Climate Change, Ozone, and Health
Are changes in climate anticipated to elevate/lower ambient ozone levels?
What are the predicted patterns?
What are the associated impacts on health?

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Epidemiological studies using national datasets
Slide 23
National Morbidity, Mortality, and Air Pollution Study (NMMAPS), 1987—2000
108 urban communities
Cause-specific mortality data from NCHS
all-cause (non-accidental), CVD, respiratory, COPD, pneumonia, accidental
Weather from NWS
Temperature, dew point, relative humidity
Air pollution data from the EPA
PM10, PM2.5, O3, NO2, SO2, CO
U.S. Census 1990, 2000

The National Medicare Cohort Study, 1999-2005 (MCAPS)
Medicare data include:
Billing claims for everyone over 65 enrolled in Medicare (~48 million people),
date of service
treatment, disease (ICD 9), costs
age, gender, and race
place of residence (ZIP code/county)

Medicare data
Nationally inclusive
Availability of hospitalization and mortality
Co-morbidity data available
Uses routinely collected data
Medical bills available for health cost estimation
Encompasses multi-site time series and cohort studies

Integrating National Databases for
Monitoring Population Health
NCHF: 48 million identification numbers
MCBS: subset of 15,000 Medicare participants with additional information on risk factors
AIRS: air pollution monitoring network
NOAA: weather monitoring network
US Census: location characteristics

Slide 28
Daily time series of hospitalization rates and PM2.5 levels in Los Angeles county (1999-2005)

Estimating temperature-health exposure-response functions
Estimating health effects (mortality and morbidity) associated with heat waves
A surveillance model to track adverse health effects associated with extreme temperatures
Link national data sources on health, environmental exposures, and confounders
Update these data bases to monitor health effects of environmental exposures over time
Use the estimated association between extreme temperature events and health using national data sets and then predict the health impact of future climate change scenarios