Diurnal temperature range and short-term mortality in large US communities

Area of Science:

• Environmental Health
• Epidemiology
• Public Health

Background:

• Diurnal temperature range (DTR) is linked to mortality in Asia.
• Limited research exists on DTR's impact on mortality in North America.

Purpose of the Study:

• To investigate the association between DTR and mortality in the United States.
• To identify specific populations and regions most affected by DTR.

Main Methods:

• Utilized daily mortality and environmental data from 95 US communities (1987-2000) via the National Morbidity Mortality Air Pollution Study (NMMAPS).
• Employed Poisson generalized linear models for community-specific DTR effect assessment.
• Applied two-level normal independent sampling estimation for region- and age-specific effects.

Main Results:

• A 1°C increase in DTR was associated with a 0.27% rise in nonaccidental mortality across the US.
• The elderly (over 65) showed increased cardiovascular (0.39%) and respiratory (0.33%) mortality with DTR changes.
• Southern California exhibited the highest DTR impact on mortality, while the Northwest and Upper Midwest showed the smallest.

Conclusions:

• DTR is significantly associated with increased nonaccidental mortality in the US.
• The elderly population is most vulnerable to DTR-related cardiovascular and respiratory mortality.
• Findings highlight regional variations in DTR's health impacts across the US.