17．High blood pressure is defined as 140mmHg over 90mmHg，and for years，doctors have used that measure as the threshold for prescribing anti-hypertensive drugs．But based on new recommendations，adults who are 60or older can wait until their readings reach 150over 90or above to begin medication．After reviewing available evidence on the effects of blood pressure treatments，the Institute of Medicine's Eighth Joint National Committee （JNC 8）concluded that aggressive treatment can lead to lightheadedness，falls and fainting in elderly populations-so they advised loosening the guidelines for starting medication．
But days after the guidelines were published，heart experts raised concerns about how the advice would affect patients； inadequately controlled blood pressure is a risk factor for heart attack and stroke．
Members of the JNC8who voted against the recommendations published an editorial in the Annals of Internal Medicine outlining their reasons for opposing the change．"We，the panel minority，believed that evidence was insufficient to increase the target goal from its current level because increasing the goal may cause harm by increasing the risk for CVD（心血管疾病）and partially undoing the remarkable progress in reducing cardiovascular mortality in Americans older than 60，"they wrote．
Dr．Suzanne Steinbaum said she has not changed the way she treats her patients over 60．She says，"As a preventive cardiologist（心臟病學(xué)家），these new guidelines have made me crazy．What we have learned is that blood pressure treatment even for a patient above 80has been shown to be critical．It goes against everything we know as cardiologists．"
Defending the panel's decision，Dr．Paul A．James，co-chairman of the guidelines committee，said in an email to TIME，"I can assure you that the panel discussed the opinions of the minority members on three different occasions and the majority were not persuaded that the expert skills of a few members should override the scientific evidence．"
James said that as with any medications，doctors will use the blood pressure recommendations as guidelines，and prescribe drugs based on their evaluation of each patient．"Medications prescribed by physicians all have the potential to be dangerous，"he wrote．"Educating doctors about the scientific evidence will help doctors make better decisions with patients．Physicians who practice on the basis of scientific evidence usually subscribe to simple rule-if the medicine cannot be shown to help the patient，then the medicine should not be prescribed．"
The editorial isn't likely to change them any time soon．But the concerns should urge doctors to monitor their patients more closely and tailor medications and their doses more carefully．
71．a(chǎn)ggressive72．recommended73．Opposition74．risk75．lack
76．unreasonable77．convincing78．educating79．rule80．careful/responsible．
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