Summer heat swings affect health of elderly patients

Daily heat swings during summer may affect the health condition of elderly people who suffer from chronic disease and reduce their expected life span. It is already known that severe heat waves in summer are associated with several health conditions and higher death rates among susceptible old people and young children. Researchers of the Harvard School of Public Health in Boston have recently found that even small daily temperature changes can cause thousands of deaths each year. Their study focused on the data of 3.7 million chronically ill people older than 65 who lived in 135 US cities between 1985 and 2006. The results demonstrated that for each increase of 1 degree Celsius in summer temperature variability, the mortality rate for the studied people rose between 2.8 percent and 4 percent, depending on their disease. For instance, the death rate increased by 4 percent for diabetics, 3.8 percent for patients with a prior heart attack, 3.7 percent for those with chronic lung disease and 2.8 percent for participants suffering from heart failure. “The effect of temperature patterns on long-term mortality has not been clear to this point,” said co-author Antonella Zanobetti whose study was published in the Proceedings of the National Academy of Sciences. “We found that, independent of heat waves, high day-to-day variability in summer temperatures shortens life expectancy.” “People adapt to the usual temperature in their city. That is why we don't expect higher mortality rates in Miami than in Minneapolis, despite the higher temperatures,” explained lead researcher Joel Schwartz. “But people do not adapt as well to increased fluctuations around the usual temperature. That finding, combined with the increasing age of the population, the increasing prevalence of chronic conditions such as diabetes and possible increases in temperature fluctuations due to climate change, means that this public health problem is likely to grow in importance in the future,” he added. Researchers predict that climate change could increase variations in summer temperatures, causing serious health risks in the mid-Atlantic countries, parts of France, Spain and Italy. They call on city governments to consider ways to increase green space, such as planting more trees and adding parks while asking people to pay more attention to elderly patients.