Daytime, Nighttime Blood Pressure Both Important
Mar. 23 -- FRIDAY, Oct. 5 (HealthDay News) -- A major study challenges the idea that high nighttime blood pressure readings are better indicators of health risk than measurements taken in the daytime.
"Our findings support recording the ambulatory blood pressure during the whole day," meaning 24 hours, concluded the report in the Oct. 6 issue of The Lancet.
The study, led by physicians at the University of Leuven in Belgium, followed almost 7,500 participants on three continents for an average of nearly 10 years.
It found that persons with higher nighttime than daytime readings did have a higher death rate, but that was because they tended to be older and sicker.
"Some people have said that blood pressure at night is the best predictor of risk," said Dr. Thomas G. Pickering, director of the Center for Cardiovascular and Behavioral Health at Columbia University. "This study says that is not actually the case, that pressure over the whole 24-hour period is [best]," said Pickering, who was not involved in the research.
Pickering chaired an American Heart Association committee that in 2005 recommended that physicians and patients move toward 24-hour blood pressure monitoring.
"We are going to make new recommendations about home blood pressure monitoring to say that it should be used much more widely than it is at the moment," he said.
High blood pressure, defined as two consecutive readings over 140/90, increases the risk of heart disease, stroke and kidney disease. An estimated 50 million Americans have high blood pressure. Many take medications for the condition and follow current guidelines for monitoring.
According to the new study, previous reports linking higher nighttime blood pressure readings with adverse outcomes needed confirmation due to major gaps in their findings. The new trial was designed to close those gaps, the researchers said.
In his accompanying editorial, Dr. Stephane Laurent, of the Universite Paris -Decartes, Paris, contends that the new findings should "significantly affect the next guidelines for ambulatory blood pressure measurement."
