Featured Research

from universities, journals, and other organizations

Study Explores The Effect Of Temperature On Mortality

Date:
January 7, 2002
Source:
Johns Hopkins University Bloomberg School Of Public Health
Summary:
The relationship between extreme temperature and mortality in the United States varies by location, according to a study from researchers at the Johns Hopkins Bloomberg School of Public Health. Excessive heat is more likely to increase mortality risk in the North, while excessive cold is more likely to increase mortality risk in the South.

The relationship between extreme temperature and mortality in the United States varies by location, according to a study from researchers at the Johns Hopkins Bloomberg School of Public Health. Excessive heat is more likely to increase mortality risk in the North, while excessive cold is more likely to increase mortality risk in the South. The study appears in the January 1, 2001 issue of the American Journal of Epidemiology.

"Historically, we know that episodes of extremely hot or cold temperatures increase mortality. Global warming and other weather phenomena, such as El Nino, have warranted the need for further investigation into the weather-mortality relation," says lead author Frank Curriero, PhD, an assistant scientist in the Department of Biostatistics at the Johns Hopkins Bloomberg School of Public Health. "We explored this relation in cities along the eastern United States, to further characterize the effects of temperature as varied by latitudes as well as other factors particular to a specific city or area."

The researchers chose 11 large metropolitan areas in the eastern United States and compared daily weather and mortality data for 1973 to 1994. The analyses was performed in two stages. First, the relationship between temperature and mortality risk from cardio-vascular, respiratory, and other diseases was estimated for each city; then the variation in risk across cities, due to difference in latitude and other variables, was examined.

Within the selected cities, mortality risk decreased as temperature increased from the coldest days; however, after a certain critical temperature threshold, referred to as the minimum mortality temperature, mortality risk increased in most of the cities as temperature increased. The minimum mortality temperature threshold ranged between approximately 65 and 70 degrees Fahrenheit for cities in the North (Boston, Chicago, New York City, Philadelphia, Baltimore, and Washington, DC) and approximately 76 and 90 degrees Fahrenheit for cities in the South (Charlotte, Atlanta, Jacksonville, Tampa, and Miami).

Results indicate the Northern cities were more sensitive to heat, showing a larger increase in mortality risk for temperatures greater than the minimum mortality temperature threshold. Southern cities were more vulnerable to cold temperatures, showing a larger increase in mortality risk for temperatures less than the minimum mortality temperature threshold.

Colder temperatures produced higher mortality risk in cities with higher proportions of elderly, but not in cities with a large fraction of heating systems. Hotter temperatures produced higher mortality risk in cities with larger percentages of persons without a high school education and those living in poverty, two indicators of socioeconomic status. A higher percentage of homes with air-conditioning was associated with small, but significant effects of hot temperature on mortality.

"Temperature at either extreme can be hazardous," advises co-author Jonathan Patz, MD, MPH, an assistant professor in the Department of Environmental Health Sciences at the Johns Hopkins Bloomberg School of Public Health. "The results of our study, however, will help guide public health interventions aimed at preventing deaths due to extreme heat and cold. These findings tell us where and to whom such interventions should be directed."

The models developed in this analysis may also be useful in estimating weather-related mortality as a consequence of future climate-change scenarios. Researchers at the School are now applying these methods to a larger number of U.S. cities to improve upon their predictive capability according to professors Jonathan Samet, MD, MS, chair of the Department of Epidemiology and Scott Zeger, PhD, chair of the Department of Biostatistics.


Story Source:

The above story is based on materials provided by Johns Hopkins University Bloomberg School Of Public Health. Note: Materials may be edited for content and length.


Cite This Page:

Johns Hopkins University Bloomberg School Of Public Health. "Study Explores The Effect Of Temperature On Mortality." ScienceDaily. ScienceDaily, 7 January 2002. <www.sciencedaily.com/releases/2002/01/020107075337.htm>.
Johns Hopkins University Bloomberg School Of Public Health. (2002, January 7). Study Explores The Effect Of Temperature On Mortality. ScienceDaily. Retrieved July 22, 2014 from www.sciencedaily.com/releases/2002/01/020107075337.htm
Johns Hopkins University Bloomberg School Of Public Health. "Study Explores The Effect Of Temperature On Mortality." ScienceDaily. www.sciencedaily.com/releases/2002/01/020107075337.htm (accessed July 22, 2014).

Share This




More Earth & Climate News

Tuesday, July 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

New Orleans Plans to Recycle Cigarette Butts

New Orleans Plans to Recycle Cigarette Butts

AP (July 21, 2014) New Orleans is the first U.S. city to participate in a large-scale recycling effort for cigarette butts. The city is rolling out dozens of containers for smokers to use when they discard their butts. (July 21) Video provided by AP
Powered by NewsLook.com
Shark Sightings a Big Catch for Cape Tourism

Shark Sightings a Big Catch for Cape Tourism

AP (July 21, 2014) A rise in shark sightings along the shores of Chatham, Massachusetts is driving a surge of eager vacationers to the beach town looking to catch a glimpse of a great white. (July 21) Video provided by AP
Powered by NewsLook.com
Spectacular Lightning Storm Hits London

Spectacular Lightning Storm Hits London

AFP (July 19, 2014) A spectaCular lightning storm struck the UK overnight Friday. Images of lightning strikes over the Shard and Tower Bridge in central London. Duration: 00:23 Video provided by AFP
Powered by NewsLook.com
A Centuries' Old British Tradition Is Far from a Swan Song

A Centuries' Old British Tradition Is Far from a Swan Song

AFP (July 19, 2014) As if it weren't enough that the Queen is the Sovereign of the UK and 15 other Commonwealth realms, she is also the owner of all Britain's unmarked swans. Duration: 02:18 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins