Adults 18-24 years old with high blood pressure were 28 percent less likely to be diagnosed during doctor visits than those 60 and older, according to findings presented at the American Heart Association's Scientific Sessions 2012.

"These young patients come to the clinic and their blood pressure is recorded," said Heather Johnson, M.D., lead researcher of the study. "They have high blood pressure, but there's no documentation of a diagnosis. We wanted to find out why."

Researchers examined electronic health records of 13,593 men and women who were at least 18 years old. All had visited their doctor at least twice within the previous three years in an outpatient, non-urgent care setting, and had multiple elevated blood pressures that met guideline criteria for a hypertension diagnosis.

Yet, after four years of visiting their doctors and accounting for other factors:

    67 percent of 18- to 24-year-olds remained undiagnosed compared to 54 percent of people 60 and older.
    65 percent of 25- to 31-year-olds were undiagnosed.
    59 percent of 32- to 39-year-olds were still living with undiagnosed high blood pressure.

Furthermore, young adults were less likely to be diagnosed if they actively smoked and if they had a mild stage of hypertension, said Johnson, an assistant professor of medicine in the division of cardiology at the University of Wisconsin School of Medicine and Public Health in Madison.

Conversely, a high blood pressure diagnosis was more likely for minorities, young adults with diabetes, severe high blood pressure, and who made more clinic visits to primary care and specialty providers.

Family practice physicians were less likely to diagnose high blood pressure than Internal Medicine physicians; however, female doctors were more likely to diagnose high blood pressure in young adults.

High blood pressure is a major risk factor for heart attack and stroke. While more prevalent in older Americans, about 29 percent of all U.S. adults have hypertension, according to American Heart Association statistics. About 11 percent of men and 7 percent of women 20-34 years old have high blood pressure.

"We know that once high blood pressure is diagnosed and young adults receive the treatment they need, they can achieve pretty high control rates," Johnson said.

Because researchers examined patient records from a large academic group practice in the Midwest, some of the predictors may vary among different healthcare systems and geographic regions, Johnson said.

Nevertheless, multiple factors must change. "Patient factors play a role, provider factors play a role, along with the healthcare system," she said. "You can't blame one component. They all must work together to diagnose and manage high blood pressure in young patients."

Johnson said she hopes the findings will "guide both patient and provider to make elevated blood pressure one of the key things to focus on during the visit."

Co-authors are: Carolyn Thorpe, Ph.D.; Christie Bartels, M.D.; Nancy Pandhi, M.D.; Ann Sheehy, M.D.; and Maureen Smith, M.D., Ph.D. The National Heart, Lung, and Blood Institute funded the study.