Heart attacks from the pills or the papers?
Is scaring the public becoming the sine qua non of medical news in the mass media? When the New England Journal of Medicine reported an unusual tuberculosis outbreak among patrons exposed to a Mycobacterium tuberculosis carrier in a barroom, Cable News Network flashed a drinking scene on the screen and asked, "Is it safe to go to bars?"
Producers and editors, claiming that their assignments reflect public interest and media responsibility, spur reporters to find these stories, most of which eventually fall down: You probably won't catch TB on a bar stool. But public anxiety, suspicion, and jadedness remain high.
The blame can be widely apportioned. Last year's clearest case in point: the near-hysteria that followed after an Associated Press writer and other reporters covered a meeting of the American Heart Association in San Antonio. Science writers sent south on assignments by their deskbound editors in the north are of course under particular pressure to produce something newsworthy. From the AHA's San Antonio press room came a story stating that calcium-channel blockers, one class of antihypertensive and antianginal drugs, increase the risk of heart attacks (which, of course, they are supposed to prevent) by 60 percent. The drugs studied were nifedipine, diltiazem, and verapamil.
"Drug for Blood Pressure Linked to Heart Attacks; Researchers Fear 6 Million Are Imperiled," screamed a March 10 Washington Post headline over the AP story. "Six million Americans taking a class of drugs to lower blood pressure may instead be increasing [their] risk of heart attacks by 60 percent, researchers reported today." The 6 million figure refers to the total number of patients taking any calcium-channel blocker; 10 drugs in this class are approved for use in the United States.
The AP report, as published in the Post, contained almost no qualification. It had only a single quotation attributed directly to the research physician, Bruce Psaty, M.D., of the University of Washington in Seattle: "[W]e are very concerned about these results," which we "believe [are] real. From a public health point of view, I think it's important."
Similar stories appeared in the Philadelphia Inquirer (on page 1) and in other newspapers. Tom Brokaw led the "NBC Nightly News" with the story on March 10. The uproar was instantaneous, as many users of calcium-channel blockers reached for the phone to call their doctors. Some--dangerously--stopped taking their drugs.
Cardiologist Edward Frohlich, M.D., of the Ochsner Medical Foundation in New Orleans told colleagues that the fallout from Psaty's study was "more of a panic than I've ever seen before in response to a medical report." Speaking at a hypertension research conference several days later, Frohlich flatly described the news reports as "irresponsible."
Some newspapers avoided fearmongering entirely, noted Harry Schwartz, Ph.D., former writer-in-residence at Columbia's College of Physicians and Surgeons, in the June 1995 Pharmaceutical Executive. The New York Times waited a day, then published a much less sensational story, refraining from extensive front-page coverage of the controversy until Sept. 1, after several peer-reviewed studies and a meta-analysis led by Curt Furberg, M.D., of Bowman Gray School of Medicine had implicated short-acting calcium-channel blockers as worsening outcome after a heart attack--and after the National Heart, Lung, and Blood Institute had issued a warning, confined to short-acting nifedipine. The Wall Street Journal skipped Psaty's March report entirely, waiting until August and September to provide routine coverage of the more extensive reports and the NHLBI warning.
What went wrong for the rest?
The initial AP article was based on a brief technical abstract and an oral report, not on a peer-reviewed publication. Unless there is truly a cause for grave public alarm, which Dr. Psaty later stated there was not, reporters and editors are unwise to run stories on such a flimsy basis. Drug studies usually are too intricate, and too demanding of context, to report on the fly.
A major source of confusion lies with the March 9 press release issued by the University of Washington, headlined "Calcium channel blocker medications prescribed for high blood pressure may increase risk of heart attack" and written in strong, unwavering language. The AP lead, including the "60 percent increase" figure, comes directly from this news release.
One key factor that neither the news release nor the AP reported was that the 60 percent figure referred to relative risk, not absolute risk. As explained later by spokespersons for the NHLBI and the AHA, the study did not mean that an individual's or group's risk of heart attack increased 60 percent if they were taking calcium-channel blockers rather than other antihypertensives. Rather, if 1,000 hypertensive patients are started on antihypertensive medications other than a calcium-channel blocker, 10 of them (1 percent) will nevertheless suffer a myocardial infarction in each given year. If they are put on a calcium-channel blocker, according to Psaty and colleagues' preliminary report and subsequent peer-reviewed case-control study, 16 of these patients (1.6 percent) will have heart attacks within that same year. The increase from 10 to 16 is 60 percent in terms of relative risk, but it is only a 6/10 of 1 percent increase in absolute risk, if the study's finding is accurate.
Early reports tended to overlook other pertinent distinctions, such as the difference between short-acting nifedipine--the specific formulation associated with an elevated risk--and the long-acting version of the drug. The vast majority of patients on nifedipine receive the newer long-acting agent: of 26.7 million prescriptions written for all forms of nifedipine in 1994, according to the detailed New York Times report on Sept. 1, about 2.1 million were for short-acting products. Dosage-related differences in risk are also important--the higher the dose given, the higher the subsequent risk--and Psaty's peer-reviewed report in the Journal of the American Medical Association acknowledges that higher dosages in some patient groups may have been simply a marker for more severe hypertension.
Reporters who jump the gun on the basis of a press release, says Columbia journalism professor Kenneth Goldstein, are more prone to such errors. "One of the biggest faults in health reporting is that most reporters don't keep following the story as they should. Stories change. A breaking story is great, but you've got to go to the original source. You've got to see the data, not the release; if you don't see the data, you get somebody's version of what the data really mean." In this case, a little patience might have spared the public a lot of panic.
--David R. Zimmerman
DAVID R. ZIMMERMAN, editor of the science and media newsletter Probe, teaches journalism at the New School for Social Research and at Columbia.
ART CREDIT: Debra Solomon