There were plenty of stories in the press today about the ALLHAT study, which showed that diuretics are still the most effective way to treat hypertension in most people. Let me say right off that I really like this kind of study, and I think that there should be more of them (more on this tomorrow – the Wall Street Journal did the best job covering this angle today.) And I don’t disagree with these findings, either – the study seems, as much as I’ve seen of it, to have been done very well and I think the data speak pretty clearly.
Most of the press coverage has been heavy on the “if not for drug company greed” angle. The New York Times gave this aspect its own story and headline. The critics have a point: pharma companies have aggressively marketed the newer mechanisms as they’ve come along, both by saying the new ones are good and that the old ones aren’t.
But if there’s any business that works differently, then I’d like the Times to tell me what it is. Some of the coverage makes it sound like Big Pharma is one large company, and Big Pharma abandoned diuretics in order to blow the horn for its more expensive drugs. But these were individual companies, and the first companies with, say, ACE inhibitors (like Merck) naturally came into the market talking about how great their new drug with the new mechanism of action was. This wasn’t Big Pharma talking, this was Merck trying to gain advantage over its competition. Nobody sent around an industry memo saying Drop Diuretics, Push ACE Inhibitors.
And as the ACE inhibitors became wildly successful, other companies got into the field, or decided that they needed to come up with new mechanisms of their own. That’s part of the free market, too – we in the pharmaceutical business get forced to come up with new stuff, because the me-too business can only go on so long. (In the case of the ACE inhibitors, it went on longer than usual, because the first generation of them had a dry cough side effect that made people stop taking them.)
You don’t hear about many of those other hypertension projects, because they didn’t live up to their potential: endothelin converting enzyme, anyone? Renin inhibitors? There were quotes today about all the excess money spent by patients over the years (by not taking diuretics.) The various drug companies who chased these (and other) mechanisms during the 1980s and 1990s would like to have some of that money back, too.
So, once we got them to work, did the drug companies push the newer hypertension medications? Well, yeah, like crazy. That’s what we do. But what we do includes the “new” part as well as the “push” part of that sentence. (The “crazy” part is another subject!)
A couple of other points: the main Times story waits until paragraph 26 to mention that there were other factors other than the Greed of Big Pharma for the move away from diuretics:
A factor in the switch from use of diuretics to newer drugs was a Swedish study reported in The New England Journal of Medicine in 1989. It found that diuretics could cause biochemical changes that were thought to increase susceptibility to heart attacks.
The other thing I’d like to mention is that some of the figures given for market share of diuretics make them seem more ignored than they are. The Wall Street Journal ran a pie chart, but it’s done by dollar sales. Because the diuretics are cheaper, they don’t make nearly as much impact in that sort of presentation. The Times ran a better graphic showing total number of prescriptions, and there’s some interesting stuff there:
While it’s true that diuretics only have about 27% of the total number of prescriptions for hypertension, they outdid ACE inhibitors every year until 2001. And they’ve beaten calcium-channel blockers (another big part of the ALLHAT study) every year, because those drugs, heavily marketed though they are, have only grown 3% in prescription volume since 1997. ACE inhibitor scrips have been up 39% in that period – and diuretics, with virtually no advertising, have been up 29%. Maybe Big Pharma isn’t getting as much bang-for-the-buck as it could with all those marketing campaigns (and maybe physicians are doing a better job exercising their judgment than today’s coverage gives them credit for.)
(Post edited next morning for clarity, emphasis, and to correct late-night typos.)