Blind Man’s Bluff
Life is full of surprises. For instance, if you’re a man who uses one of the popular medications that address erectile dysfunction (ED), you and Bob Dole could be in for a very unpleasant surprise.
But before we examine the dark mysteries of ED drugs, let’s see what happens when a researcher researches research.
The headliner
Long-time e-Alert readers may have noticed that one of my pet peeves is the wild inaccuracy often found in news headlines. When a headline writer states that vitamin E, for instance, is “proven” to have no beneficial effects on heart health, and then the research behind the news item turns out to be deeply flawedthat’s when I see red. At best, this is simply lazy and sloppy. At worst, these headlines may mislead some consumers into making poor health choices.
So I’m always on the lookout for off-the-mark headlines. And I thought I’d found another one the other day when I came across this head above an Associated Press (AP) item: “What’s ‘good for you’ often ends up being bad.”
Uh oh, I thought. Here we go. But instead I found a very interesting article about research, conducted by John P. A. Ioannidis, M.D., of the University of Ioannina School of Medicine in Greece. Dr. Ioannidis searched through more than a decade of studies published in Lancet, The New England Journal of Medicine (NEJM), and the Journal of the American Medical Association (JAMA; where, coincidentally, Dr. Ioannidis’ study was published earlier this month).
Dr. Ioannidis found nearly 50 original clinical research studies that had repeated follow up studies published between 1990 and 2003. Forty-five of the original studies concluded that the treatment being researched was effective. But in the follow-ups, 16 percent concluded that the treatments were ineffective, while another 16 percent concluded that the effects of treatment were stronger than the original studies found them to be.
In the AP article the editors of NEJM noted how important it is to recognize that, “A single study is not the final word.” – an outlook I’ve frequently expressed in the e-Alert.
But my favorite quote in the article comes from Catherine DeAngelis; the editor of JAMA, who told the AP that matters get even more complicated when the media produces “misleading or exaggerated headlines.”
With you all the way on that one, Dr. D!
Case in point
To illustrate Dr. Ioannidis’ point about needing more than just one study to uncover the full range of pros and cons of a treatment, we only need to look at a drug that’s received more than 100 clinical trials. That’s right – it’s the wildly popular erectile dysfunction drug that has achieved cultural icon status in less than a decade: Viagra.
According to a Washington Post article, NONE of those 100+ trials picked up on a rare but severe side effect of the drug: Men who have diabetes, hypertension or high cholesterol may experience sudden partial blindness. This past spring the Journal of Neuro-Ophthalmology carried a report that examined seven men, aged 50 to 70, who developed this side effect – known as nonarteritic anterior ischemic optic neuropathy (NAION) – within 36 hours of taking Viagra. In some cases, vision wasn’t completely restored.
In addition, the Post reports that the FDA has received more than 35 complaints from Viagra users who suffered sudden and permanent loss of sight in one eye. CBS News claims that number may be much higher: perhaps more than 100 cases.
As a result of this surprising development the FDA has “approved updated labeling” for Viagra and other ED drugs. This note appeared in last week’s FDA News Digest: “FDA urges patients taking these drugs who experience sudden vision loss or decreased vision in one or both eyes to stop taking the drug and contact a medical professional right away.”
It’s priceless: If everything suddenly goes dark or blurry or blue, just read (or attempt to read) the information sheet that came with the medication; printed in microscopic typeface, of course. And then try to find the phone to call your doctor.
It’s hard to say what treatment a doctor might suggest for this unique condition, but you can bet he probably won’t be aware that an FDA safety officer informed her superiors of the blindness danger more than a YEAR before the Journal of Neuro-Ophthalmology study was published (according to the Post).
In the bureaucratic mind, information isn’t power, regulation is power. FDA officials can’t just issue a well-publicized statement when they detect an obvious danger. They have to sit on the information while the wheels of bureaucracy slowly grind out a requirement for a warning on the drug’s information sheet.
So if you know any men who use Viagra, Levitra or Cialis, give them the news that will eventually be mentioned somewhere on drug information sheets: When these medications are taken by those with diabetes, hypertension or high cholesterol, there’s a chance that everything might go dim. Permanently.
Sources:
“What’s ‘Good For You’ Often Ends Up Being Bad” The Associated Press, 7/12/05, msnbc.com
“Contradicted and Initially Stronger Effects in Highly Cited Clinical Research” Journal of the American Medical Association, Vol. 294, No. 2, 7/13/05, jama.ama-assn.org
“FDA Was Told of Viagra-Blindness Link Months Ago” Marc Kaufman, Washington Post, 7/1/05, washingtonpost.com
“Reports of Eye Problems Prompt Label Change for Impotence Drugs” FDA News Digest, 7/11/05, list.nih.gov
