Saturday, February 11, 2012

Medications Likely Do You No Good

You might freak out when you realize how likely it is that your medication will do you no good.
There’s a very important term in medicine that is often ignored, it is “Number Needed to Treat.”
It means, how many people have to take the medication for one of them to avoid the bad outcome.

For example – why do people take Lipitor?
 - So they don’t have a heart attack or stroke and then die or become seriously impaired.
What does Lipitor do?
 - It lowers cholesterol
Why lower Cholesterol?
 - To avoid clogging arteries.
Why avoid clogged arteries?
 - To prevent a heart attack or stroke
Why prevent a heart attack or stroke?
 - to prevent death or serious impairment.
How many people have to take Lipitor to prevent one of them from dying or becoming seriously impaired?
 - 500. 

Okay – forget death or impairment, let’s just talk about a heart attack
How many people have to take Lipitor to prevent one of them from having a heart attack?
- 100.  Yeah.  One hundred people have to take Lipitor for 3 years in order to prevent one heart attack.

And Lipitor isn’t the worst drug, not by far.

Zetia is also taken to lower cholesterol – but it’s NNT is so high it isn’t shown to prevent any heart attacks at all.  Over 1000 people have to take it just to avoid heart disease.
How about aspirin?  Its NNT is 350.

Well what about exercise?  What is exercise’s NNT for preventing a heart attack? 
 - 3.  For every three people who exercise regularly, one of them will be saved from having a heart attack.

All of these number are speaking about healthy people, but it’s still poor even for those who already have disease.
Take people who already have heart disease or have had a heart attack.  How many of them have to take Lipitor to prevent one heart attack?  20.

You’ve had a heart attack, is it worth the 1 in 20 chance to pay for and take a pill every single day?
You just have high blood pressure, is it worth the 1 in 250 chance then?  Is it worth $500-$1000 per year to take a pill that has a 1/250 chance of helping you?
Okay  - forget the money.  What about the side effects?  Lipitor can cause diarrhea, muscle pain, nausea, headache, etc…  Is it worth it to take a pill knowing that the only effect it will most likely have is negative?
Remember, Lipitor is one of the BEST drugs that way.  It's side effects are fairly mild and what it prevents is fatal.  Even so, with such a small chance of benefit, is it worth it?

My point is this.  Medications cost money and they have side effects.  They work, but not nearly as well as most people think.  They bring peace of mind, they correct lab values, and for a small number of people, they prevent a bad outcome.
I am not callous or disinterested.  I prescribe medications every day with this knowledge.  I know my own family history and I’m going to be watching my cholesterol levels like a hawk the rest of my life.  Nevertheless, it is disheartening to know that for the HUGE majority of people taking medication, it will have no positive effect in their life whatsoever.

1 comment:

Dave Wyman said...

Interesting article. My comments:

First, I have had a heart attack and I don't take statins. However, I feel somewhat like a global warming denier, one who thinks humans arent at least partially to blame, when all the evidence shows otherwise.

Second, if statins do save one out of 100 lives after three years, or one out of 20 of those who've had a heart attack, given the millions of people with heart disease, that's saving a lot of lives.

Is exercise better than taking Lipitor? Sure. I exercise a lot. And I' m pretty sure my heart attack was caused by a combination of extreme personal streas for two years, plus fammily history of heart disease.

Even on a statin, though, after my heart attack, more plaque in my arteries grew enough that I needed two more stents.

Eventually I was put on a high dose statin. You didn't address it in your blog, but a recent study seemed to indicate that a high statin dose can reverse plaque and prevent far more heart attacks.

PLUS: wouldn't the potential slight risk reduction a statin confers simply be added to the risk reduction gained by exercise? Doesn't it all add up?

You would l not say, "It's great that you ae exercising, now you don't need to stop smoking or overrating."

So why NOT take a statin? Muscle pain? Stop taking the statin. Memory loss? Stop taking the statin.

Finally, my cardiologist insists a statin can keep plaque "stable, keep it from breaking off and blocking an artery.

I don't take a statin because I don't have much plaque, anymore, because I had some muscle pain, because I suspect it's doing other things to my body that I don't know about, and because I don't smoke, or over eat, I got rid of the stress, and there's all that exercise I do, all of which I think is risk reduction enough.