Should we all be on statins? (reprise)

Should you be on statins? New guidelines and an online calculator may allow you to answer this question yourself.

Back in 2011, I asked whether we should all be on statins. At the time, it was clear that statins offered benefits for people who had already suffered heart attacks or other serious cardiovascular problems. But for the rest of us, it wasn't clear at all. A number of studies had been published suggesting that millions more people (in the U.S. alone) might benefit from statin therapy, but most of those studies were published by drug companies that made statins. As I wrote at the time, "we need more data from completely unbiased studies."

So has anything changed? Actually, it has. Last year, the U.S. Preventative Services Task Force (USPSTF) reviewed all of the evidence and updated its former (from 2008) recommendations. The evidence now suggests that some people–even those who have never suffered a heart attack–would benefit from statins.

Here's what the current USPSTF recommendations suggest. If you've never had a heart attack and have no history of heart disease, you still might benefit from statins if:

  • you're 40-75 years old,
  • you have one or more "risk factors" for cardiovascular disease (more about this below), AND
  • you have a 10-year risk of cardiovascular disease (CVD) of 7.5%-10%, using a "risk calculator" that I'll link to below.

Now let's look at those risk factors for CVD. There are four of these, and any one of them puts you in the category of people who might benefit from statins: diabetes, high blood pressure (hypertension), smoking, or dyslipidemia.

Most people already know their status for the first 3, but "dyslipidemia" needs a bit more explanation. This is simply an unhealthy level of blood cholesterol, defined by USPSTF as either "an LDL-C level greater than 130 mg/dL or a high-density lipoprotein cholesterol (HDL-C) level less than 40 mg/dL." You can ask your doctor about these numbers, or just look at your cholesterol tests yourself, where they should be clearly marked.

For that last item, how do you calculate you 10-year risk of CVD? Most people should ask their doctor, but if you want to see how it's done, the calculator is at the American College of Cardiology site here. It's quite simple and you can fill it in yourself to see your risk.

A big caveat here, as the USPSTF explains, is that the "risk calculator has been the source of some controversy, as several investigators not involved with its development have found that it overestimates risk when applied to more contemporary US cohorts."

Another problem that I noticed with the risk calculator is that using it for the statin recommendation involves some serious double counting. That's because the risk calculator relies in part on your cholesterol levels and blood pressure, but those same measurements are considered to be separate risk factors for CVD. This puts a lot of weight on cholesterol levels–but on the other hand, statins' biggest effect is to reduce those levels.

The USPSTF is a much more honest broker of statin recommendations than industry-funded drug studies, so we can probably trust these new guidelines. Note that if the risk calculator puts you in the 7.5%-10% range, you will only get a very small benefit from statins–as the USPSTF puts it, "Fewer persons in this population will benefit from the intervention."

Don't rush to go on statins without giving it some serious thought. As Dr. Malcolm Kendrik put it last year (quoted by Dr. Luisa Dillner in The Guardian),
“If I was taking a tablet every day for the rest of my life, I would want to know how long I would have extra to live. If you take statins for five years and you are at higher risk, then you reduce the risk of a heart attack by 36%. But if you rephrase the data, this means on average you will have an extra 4.1 days of life.” 
So no, we shouldn't all be on statins. But until something better comes along (and I hope it will), they are worth considering for anyone who is in a higher-risk group for cardiovascular disease.

No comments:

Post a Comment

Markup Key:
- <b>bold</b> = bold
- <i>italic</i> = italic
- <a href="http://www.fieldofscience.com/">FoS</a> = FoS