Outdoor Temperature Affects Blood Pressure in Elderly
Careful monitoring during extreme outdoor temperatures could reduce mortality risk
TUESDAY, Jan. 13 (HealthDay News) -- There is a strong association between outdoor air temperature and blood pressure in the elderly, and monitoring should be stepped up during times of extreme heat or cold, according to a report published in the Jan. 12 issue of the Archives of Internal Medicine.
Annick Alperovitch, M.D., of INSERM in Paris, France, and colleagues conducted a study of 8,801 individuals aged 65 and older by measuring blood pressure at baseline and two years later. Local meteorological offices provided daily outdoor temperature measurements.
As outside temperatures increased, systolic blood pressure decreased with a difference of 8.0-mm Hg between less than 7.9 degrees Celsius and 21.2 degrees Celsius and above, the investigators found. There was also a strong correlation between individual blood pressure differences at baseline and follow-up, and difference in outside air temperature, the researchers report. The longitudinal effects of outside air temperature were more pronounced in subjects aged 80 and older versus their younger counterparts, the report indicates.
"In August 2003, there was an unprecedented heat wave in France that resulted in about 15,000 deaths, mainly in the elderly. This heat wave affected the blood pressure of the study participants who had their second follow-up examination during this period," the authors write. "Because decreased blood pressure may be a risk factor for increased mortality in persons with environmental hyperthermia, monitoring of blood pressure in the elderly could be an important issue under these extreme conditions."