Higher blood pressure limit for over-60s set in new US guidelines
Over-60s don't need medication if pressure is below 150/90, new guidelines say, but some doctors unhappy with first revision in 30 years
New US guidelines suggest that people older than 60 can have a higher blood pressure than previously recommended before starting treatment to lower it. The advice, criticised by some doctors, changes treatment goals that have been in place for more than 30 years.
Until now, people were told to strive for blood pressures below 140/90, with some taking multiple drugs to achieve that goal. But the guidelines committee, which spent five years reviewing evidence, concluded that the goal for people over 60 should be a systolic pressure of less than 150. They said the diastolic goal should remain less than 90.
Systolic blood pressure, the top number, indicates the pressure on blood vessels when the heart contracts. Diastolic, the bottom number, refers to pressure on blood vessels when the heart relaxes between beats.
The committee determined that there was not strong evidence for the blood pressure targets, and there were risks associated with the medications used to bring pressures down.
The committee, composed of 17 academics, was tasked with updating guidelines last formulated a decade ago. Their report was published online on Wednesday in the Journal of the American Medical Association.
Hypertension experts said they did not have a precise figure on how many Americans would be affected, but Dr William White, president of the American Society of Hypertension, said it was "a huge number for sure".
He estimated that millions of people in the US are over 60 and have blood pressures between 140 and 150.
Dr Paul James, chairman of the Department of Family Medicine at the University of Iowa and co-chairman of the guidelines committee, said: "If you get patients' blood pressure below 150, I believe you are doing as well as can be done based on scientific evidence."
The group said people older than 60 who are taking drugs and have lowered their blood pressure to less than 150 could continue if they were not experiencing side effects.
But, it cautioned, although efforts to lower blood pressure have had a remarkable effect, reducing the incidence of strokes and heart disease, there is a difference between lowering blood pressure with drugs and having lower pressure naturally.
Medications that lower blood pressure can have side effects that counteract some of the benefits, said Dr Suzanne Oparil, a co-chairwoman of the committee. For that reason, maximum benefits may occur with less intense treatment and higher blood pressure.
"The mantra of blood pressure experts in the past has been that lower is better," Oparil said. "Recent studies don't seem to support that."
Two Japanese studies in older people found those who reduced their systolic pressure to less than 140 fared no better than those who reduced it to between 140 and 160, or between 140 and 149.
Some experts not on the committee said that the old blood pressure guidelines were based on limited science, but that this did not mean that goal should be abandoned.
"When I discuss this with my colleagues and friends in the community, most are pretty livid," said Dr George Bakris, director of the hypertension centre at the University of Chicago.
The old targets made a huge difference in patients' health, said Dr Marvin Moser, a hypertension expert, who was chairman of the first blood pressure guidelines committee in 1977 and a member of the six committees after that, but not of the most recent one.
"The thing about hypertension is that it is a dull disease, but the results of treatment are spectacular," he said. The incidence of strokes has fallen by 70 per cent since 1972, and heart failure rates by more than 50 per cent.
"It used to be that every third or fourth hospital bed had someone with hypertension in it," Moser said.