Who Needs Those Cholesterol Pills, Anyway? (numbers needed to treat)

[Guest guest]

Who Needs Those Cholesterol Pills, Anyway?

January 18th, 2008 4:00 pm By Ed Silverman

That's the question pondered in a BusinessWeek piece, and the answer offered - very few. To illustrate the point, the fine print in a Lipitor ad is cited - in a large clinical study lasting more than three years, 3 percent of patients taking a placebo had a heart attack, compared with 2 percent on the Pfizer pill. This means for every 100 people, three people on placebos and two people on Lipitor had heart attacks.

The difference credited to the drug? One fewer heart attack per 100 people. So to spare one person a heart attack, 100 people had to take Lipitor for more than three years. The other 99 got no measurable benefit. In other words, the number needed to treat (or NNT) for one person to benefit is 100. And the mag notes there are reasons to believe the overall benefit for many patients is even less than what the NNT score of 100 suggests, because it was determined in an industry-sponsored trial using carefully selected patients with multiple risk factors, which include high blood pressure or smoking.

"Anything over an NNT of 50 is worse than a lottery," Nortin Hadler, professor of medicine at the University of North Carolina at Chapel Hill and a longtime drug industry critic, tells the mag. "There may be no winners." Drugmakers, however, advertise big percentage drops in, say, heart attacks, while obscuring the NNT. But when it comes to side effects, they flip-flop the message, dismissing concerns by saying only 1 in 100 people suffers a side effect, even if that represents a 50 percent increase. (Click on the BusinessWeek chart for a clearer view).

Several recent scientific papers, meanwhile, peg the NNT for statins at 250 and up for lower-risk patients, even if they take it for five years or more. "What if you put 250 people in a room and told them they would each pay $1,000 a year for a drug they would have to take every day, that many would get diarrhea and muscle pain, and that 249 would have no benefit? And that they could do just as well by exercising?" asks Jerome Hoffman, professor of clinical medicine at the University of California at Los Angeles. "How many would take that?"

Probably not too many. But for those willing to gamble, Mack at PharmaMarketing, who drew this to our attention, is collecting your money