What are the new normal blood pressure goals, and how have they changed for the elderly? Controlling high blood pressure is a good thing—unless you are a frail older person. Then it might be harmful. That's the surprising finding of a study of more than 2,000 seniors published online in the Archives of Internal Medicine.

Make no mistake: high blood pressure is a definite health hazard. It damages arteries in the heart, kidneys, and throughout the body, leading to heart attack, heart failure, stroke, kidney failure, and other serious health problems. That's why many doctors recommend aggressive steps for lowering high blood pressure.

But as we are learning about other conditions, a one-size-fits-all approach doesn't work. What is right for controlling blood pressure in a 50-year-old might not work for a frail 80-year-old.

Blood pressure for aging seniors and elderly

Researchers looked at information collected as part of the U.S. National Health and Nutrition Examination Survey. People participating in it had their blood pressure checked; they also took a walking test that measured how long it took them to cover 20 feet. Based on this test, researchers divided the participants into three groups: those who finished the 20-foot walk in under eight seconds, those who took longer than that, and those who weren't able to complete the walk.

Blood pressure goals

Normal blood pressure is a systolic pressure of less than 120 and a diastolic pressure of less than 80. Systolic pressure (the upper number in a blood pressure reading) refers to pressure in the arteries when the heart beats. Diastolic pressure (the lower number) measures pressure in the arteries between heart beats. But when and how to treat blood pressure to reach a particular goal will depend on multiple factors, such as your age and other cardiovascular risk factors.

Among elderly adults, higher systolic blood pressure (the top number of a blood pressure reading) was linked to a greater likelihood of dying over the five-year study only among faster walkers. Among the participants who couldn't even walk 20 feet, those with high blood pressure were less likely to have died.

"Older frail adults might benefit from slightly higher blood pressure," study author Michelle Odden, a public health epidemiologist at Oregon State University, told HealthDay. "As the blood vessels get more stiff with age, it may be necessary to have more pressure to keep blood pumping to the central organs, like the brain and heart."

It's also possible that using multiple medications drive down blood pressure in frail older adults may do more harm than good. That's because all medications have side effects, and these side effects may have a greater impact on older, frail adults than their healthier counterparts.