May 25, 2011 -- Close to 19% of young adults may have high blood pressure, and just half of them are aware of it despite this condition's strong link to heart attack and stroke risk, according to a new study.
"There is a sleeping epidemic among young adults," says study researcher Kathleen Mullan Harris, PhD, the interim director of the University of North Carolina’s Carolina Population Center in Chapel Hill. "We tend to think of them as a rather healthy group, but a prevalence of 19% with hypertension is alarming."
The new findings, which appear in Epidemiology, are much higher than previous estimates of the prevalence of high blood pressure in this same age group. The National Health and Nutrition Examination Survey 2007-2008 showed that 4% of people aged 20 to 39 had high blood pressure.
Exactly why there is such a wide gap between the two estimates is not fully understood. "Both were carefully done and highly reputable studies, and the true prevalence is probably somewhere in between these two estimates," says Harris.
Both studies analyzed blood pressure measurements of similar age groups around the same time (2007-2008), and both studies defined high blood pressure as 140/90 or higher.
The new 19% prevalence estimates are based on data from the National Longitudinal Study of Adolescent Health (Add Health), which looked at more than 14,000 men and women aged 24 to 32.
The Add Health study is one of the first to focus solely on the heart health of young adults. The participants have been followed for cardiovascular risk factors including obesity since 1995. When participants were aged 12 to 19, 11% were obese; five years later, 22% were obese; five to six years later when they were aged 24 to 32, 37% were obese, the new study shows.
The study asks more questions than it answers at this point, says Steven Hirschfeld, MD, associate director for clinical research for the Eunice Kennedy Shriver National Institute of Child Health and Human Development in Bethesda, Md.
The findings "emphasize the need to continue to monitor high blood pressure in young adults, but don’t necessarily recalibrate what is normal or what is abnormal," he says.
"We need to look at this report in more detail," he says. "It is too early to make any public health recommendations based on one study."
The differences between the two studies could be due to the time of year that the blood pressure readings were taken, for example, he says.
"We also don’t know what effect this measurement would have on health," he says. "It is a one-time measurement and we don’t know where these participants were 10 years ago and where they will be 10 years from now."