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Health & wellness

In Practice

Navigating changes in medical guidelines

Dan Page for the boston globe

The other day I was taking the blood pressure of a healthy but somewhat anxious elderly woman who came in for a routine checkup.

“Normal!” I pronounced. “146/90.”

“So I don’t need medication?” she asked.

“Nope.”

“How do you know?”

“Because your blood pressure is fine.”

“Are you sure? That sounds kind of high to me.”

I was sure. But the truth is, a month earlier I would have been just as sure that my patient’s blood pressure was not fine. In December 2013 a panel of experts appointed by the National Heart, Lung, and Blood Institute recommended that the threshold for treating people over 60 years old for hypertension be raised from 140/90 to 150/90. The panel determined that there was little evidence that lowering systolic blood pressures between 140 and 149 in older people caused them more good than harm.

This change may seem small but it meant that, literally overnight, roughly 7 million older Americans with high blood pressure, half of whom were taking medication, no longer had that condition. (The expert panel did not recommend that those already taking and tolerating medication discontinue it.)

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The reversal of decades-old treatment guidelines has huge public health and economic implications. It can also affect both patients and doctors psychologically.

Even after I explain the rationale for the change, a patient might feel uneasy walking around with a blood pressure I’d been telling her for years could put her at risk for heart attack and stroke. The patient might feel less confident in my advice on other medical issues because, after all, I could switch my recommendations on those too.

As for me, every new alteration in the standard of medical care leaves me feeling a bit like Miss Emily Litella, the character Gilda Radner played years ago on “Saturday Night Live.” Miss Litella would go on some impassioned but wrong-headed rant and then, after she’d been gently corrected, would retreat with a meek “Never mind.”

I’ve been thinking a lot about how shifting standards affect the doctor-patient relationship because in the past few weeks, in addition to the announcement about hypertension, radically new guidelines for the use of cholesterol lowering drugs have been released. These guidelines, set forth by the American Heart Association and the American College of Cardiology, recommend statin drugs for those at risk of heart attack and stroke — based on a risk-factor calculator — regardless of their actual cholesterol levels. Now I’ll have to tell patients, in effect: “Those numbers we’ve been tracking vigilantly for so long? . . . Never mind.”

High blood pressure and high cholesterol join a long list of medical conditions whose diagnosis and treatment have changed substantially in the past several years. Based on recommendations set by organizations such as the American College of Physicians, the Centers for Disease Control and Prevention and others (there is no single source for medical guidelines), I’ve changed the way I approach most common medical issues.

Just a few examples: I don’t suggest, as I once did, that most women have a baseline mammogram at age 35; I urge everyone (not just chronically ill and older people) to have annual flu shots; I discourage women from using hormone replacement therapy simply because they’ve reached menopause (a formerly routine practice); I no longer advise all women to have a yearly Pap test.

Pap tests screen for cervical cancer, which is caused by human papillomavirus. Because HPV is sexually transmitted, women at no or low risk for STDs have little chance of developing cervical cancer. In 2012, the US Preventive Services Task Force and other organizations advised that most women need the test only every three years and that women over age 65 who’ve had normal Paps can skip them altogether.

I’ve been fascinated with my patients’ varied reactions to the new Pap guidelines. Some are delighted (who likes Pap tests?). Some express concern that the new recommendations are part of a plan to ration healthcare, maybe related to the Affordable Care Act (they’re not). Many women, after listening to my spiel about HPV and the low risk of cervical cancer, want the test anyway. And how can I blame them? After decades of hearing from doctors and public service announcements how important it is to have an annual Pap test, it must feel a little nerve-racking to leave my office without one.

I confess that even though I fully understand the reasons for the new guidelines, I still sometimes feel a little queasy implementing them.

Changing guidelines, at least temporarily, disorient and discomfort both doctors and patients. They also challenge some of our most basic beliefs. If a press release can cure your high blood pressure, make you fat (as happened in 1998 when the threshold for “overweight” was lowered), or seem to raise or reduce your risk for cancer in an instant, then isn’t health really just a subjective and mutable concept? And though we doctors acknowledge that our profession is at least as much art as science, each new clinical recommendation reminds us that “science” isn’t a synonym for “fact” — it’s an often imperfect process for discovering truth. At any given time we do the best we can with what we know, accepting that what we know is incomplete.

Older doctors and patients understand this best, I think. They remember when physicians prescribed milk diets for ulcers, blamed insufficiently affectionate “refrigerator” mothers for their children’s autism and schizophrenia, and enforced strict bed rest for weeks after a heart attack. The long perspective teaches that even when we’re certain we know the right answer in medicine, it’s best to maintain our curiosity — and our humility.

That patient who was skeptical about the new blood pressure standards reminded me of this. After I promised her 146/90 was OK and she didn’t need any medication, she teased, “So, what you’re telling me is that I’m going to live forever?” “Absolutely,” I joked back.

“Ha!” she snorted. “I’ll bet you’re sure about that too.”

Dr. Suzanne Koven, a primary care internist at Massachusetts General Hospital, can be reached at inpracticemd@gmail.com. Read her blog on Boston.com/Health.

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