updated 5/25/2011 1:48:07 PM ET
But only half of those adults, who were ages 24 to 32, have been told by a doctor that they are hypertensive, which shows that not everyone may be aware that they have the symptomless disease, said study researcher Dr. Eric Whitsel, an assistant professor in medicine and epidemiology at the University of North Carolina at Chapel Hill.
If a younger adult goes to a doctor for a checkup, the doctor will likely screen for high blood pressure. But “if people aren’t visiting health care professionals and aren’t measuring their blood pressure at home using inexpensive monitors, then they won't capture their illness," Whitsel told MyHealthNewsDaily.
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Diagnosis and treatment of high blood pressure are important because, if left untreated, it can lead to heart disease, heart attack and stroke.
The new study was published online today (May 25) in the journal Epidemiology.
Who has high blood pressure?
Researchers analyzed health data from 14,000 men and women ages 24 to 32 who participated in the National Longitudinal Study of Adolescent Health, also known as the Add Health study.
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They found that of those people, 19 percent had high blood pressure — that is, they had a blood pressure reading of 140/90 millimeters of mercury or higher.
"And we found the results across every demographic: age, race, ethnicity, gender and level of obesity," Whitsel said. "So it didn’t seem like it was concentrated within a particular group of individuals."
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However, some trends did emerge. Researchers found that men were more likely than women to have hypertension (27 percent of men, versus 11 percent of women).
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College-educated adults were less likely to have high blood pressure than people who have only a high school diploma (22 percent of college-educated people, versus 17 percent of high school-educated people), according to the study.
The results were surprising because a previous study, the National Health and Nutrition Examination Survey, also conducted around 2008, showed that only 4 percent of young adults had hypertension, said study researcher Kathleen Mullan Harris, interim director of the Carolina Population Center at the University of North Carolina at Chapel Hill.
Possible reasons for some of the discrepancy in the findings are differing characteristics of the study participants and the accuracy of the blood pressure readings, she said. But researchers found that none of these reasons could possibly account for such a large discrepancy in both studies' results, Harris said.
How to keep blood pressure down
High blood pressure is caused by a mix of social, behavioral and biological factors, Harris said. However, the study makes it clear that high blood pressure in young adulthood is the manifestation of an unhealthy lifestyle, she said.
"This stage of early adulthood is when young people move out of the house, get into regular lifestyle choices and develop habits that will last into adulthood," Harris told MyHealthNewsDaily. "So we think this is an important time of the life course to bring attention to their health and screen for such conditions like high blood pressure that are asymptomatic."
Whitsel offered four ways to keep high blood pressure from getting too high:
1. Eat a balanced and healthy diet high in fruits and vegetables.
2. Reduce intake of sodium, which has a prominent effect on blood pressure levels, to less than 2,300 milligrams per day.
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3. Limit daily alcohol consumption to two drinks or less for men and one drink or less for women.
4. Make sure you exercise regularly. Adults should get at least 150 minutes of moderate to vigorous physical activity every week, according to the Centers for Disease Control and Prevention.
There are also a number of drugs that can treat high blood pressure, including beta blockers, calcium channel blockers and angiotensin-converting enzyme (ACE) inhibitors.
Pass it on: High blood pressure doesn't have any symptoms, so it's important to get screened by a doctor to make sure your blood pressure isn't too high.
Follow MyHealthNewsDaily staff writer Amanda Chan on Twitter @AmandaLChan.