Number Needed to Treat (NNT) website and Statin Drugs

My 85 year old mother-in-law was placed on a statin drug two years ago by her primary care physician. She had no risk factors for coronary disease other than age, she had a prior completely normal cardiac catheterization (coronary angiogram) and was totally without symptoms before being placed on the statin. Within weeks she developed muscle pain and weakness, suffered fatigue and overall felt poorly. I convinced her to stop the statin and within a few weeks she felt great. I see similar scenarios frequently in the pain clinic. I personally suffered severe statin induced myopathy pain from two different statins (in the days before enlightenment) and gratefully recovered when I stopped the drug each time. I have since learned more about coronary artery disease, cholesterol metabolism, statins, and related topics.

There is a great website that analyzes data from multiple studies to estimate the number of patients needed to treat in order to help and/or harm a patient. Two such analyses on this website are the NNT with statin drugs for five years to achieve certain results. They analyze data  in patients without known coronary artery disease (primary prophylaxis) and in patients with known coronary artery disease (secondary prophylaxis).

Here is the website:

TheNNT

Here is the page for primary prophylaxis:

Statins for Heart Disease Prevention (Without Prior Heart Disease) | TheNNT

Here is the link to the page on secondary prophylaxis:

Statins for Heart Disease Prevention (With Known Heart Disease) | TheNNT

Here are the results for primary prophylaxis.

“In Summary, for those who took the statin for 5 years:

  • 98% saw no benefit
  • 0% were helped by being saved from death
  • 1.6% were helped by preventing a heart attack
  • 0.4% were helped by preventing a stroke
  • 1.5% were harmed by developing diabetes*
  • 10% were harmed by muscle damage

In Other Words:

  • None were helped (life saved)
  • 1 in 60 were helped (preventing heart attack)
  • 1 in 268 were helped (preventing stroke)
  • 1 in 67 were harmed (develop diabetes*)
  • 1 in 10 were harmed (muscle damage)”

Here are the results for secondary prophylaxis.

“In Summary, for those who took the statin for 5 years:

  • 96% saw no benefit
  • 1.2% were helped by being saved from death
  • 2.6% were helped by preventing a repeat heart attack
  • 0.8% were helped by preventing a stroke
  • 0.6% were harmed by developing diabetes*

In Other Words:

  • 1 in 83 were helped (life saved)
  • 1 in 39 were helped (preventing non-fatal heart attack)
  • 1 in 125 were helped (preventing stroke)
  • 1 in 167 were harmed (develop diabetes*)”

If anything, the side effects (harm) are understated and the authors acknowledge this because many of the studies do not adequately report side effects and complications. (The studies were funded in part or in totality by the pharmaceutical company that makes the drug and that is a problem as discussed below)

Association of funding and conclusions in randomized dr… [JAMA. 2003] – PubMed – NCBI

It is rare that this sort of analysis would be presented to a patient in the physician’s office to help a patient decide whether the risks and benefits are acceptable. (I provide patients with this data on a multi-page handout with significant narrative and explanation when I diagnose statin myopathy.)

The obsession that American physicians have with cholesterol (another topic to be addressed in future posts) creates a knee-jerk reaction to a lab value that results too often in muscle damage and pain and sometimes cognitive impairment.

My experience in the pain clinic has been that the % of elderly with statin induced muscle damage and/or muscle pain is much higher. When I suggest that the patient stop the statin drug because they are suffering disabling pain and possibly permanent muscle damage they often return at the next visit to tell me they were started on a different statin drug. Most patients who suffer this complication will have a repeat of the same complication when placed on a different statin drug. This complication can cause permanent damage.

In the medical literature, many studies presented as “primary prophylaxis” are not truly primary prophylaxis because there are some patients included that have known diagnosed coronary disease. This tainted data is then presented as if it were a true primary prophylaxis study.

A more recent study purported to demonstrate once and for all that statins in primary prophylaxis can save lives. Unfortunately, there were problems with this study as well. Here is an excerpt from a commentary in the publishing journal:

“There are reasons to be cautious about the findings of the meta-analysis by Taylor and colleagues. As the authors note, all but 1 of the trials were partly or fully funded by pharmaceutical companies. Trials funded by for-profit organizations are more likely to recommend the experimental drug than are trials funded by nonprofit organizations (4). Further, adverse event reporting in the original trials was poor, with few details about type or severity, and quality of life was rarely assessed. Some adverse events, such as cognitive impairment, are rarer and not assessed.”

Disappointingly, the commentary failed to point out that the study data again included some patients with diagnosed coronary artery disease. (up to 10%).

Here are the authors own words.

“We included randomized controlled trials of statins versus placebo or usual care control with minimum treatment duration of one year and follow-up of six months, in adults with no restrictions on total, low density lipoprotein (LDL) or high density lipoprotein (HDL) cholesterol levels, and where 10% or less had a history of CVD.”

Once again we have a “primary prophylaxis” meta-analysis that is not really a primary prophylaxis study. It never seems to end.

When drug companies fund studies the conclusions often overstate the benefit and understate the risks. If you do not look for a side effect or complication, you will not find one. Here is an excerpt from a large study that look at the issue of bias in drug company sponsored research.

“CONTEXT:

Previous studies indicate that industry-sponsored trials tend to draw proindustry conclusions.

OBJECTIVE:

To explore whether the association between funding and conclusions in randomized drug trials reflects treatment effects or adverse events.

CONCLUSIONS:

Conclusions in trials funded by for-profit organizations may be more positive due to biased interpretation of trial results. Readers should carefully evaluate whether conclusions in randomized trials are supported by data.”

Association of funding and conclusions in randomized dr… [JAMA. 2003] – PubMed – NCBI

There are many ways that authors can present data to give the appearance of success. A more recent study published in Lancet alleged to demonstrate benefit (death prevention) for statins in primary prophylaxis.

Here it is.

The effects of lowering LDL cholesterol with statin therapy in people at low risk of vascular disease: meta-analysis of individual data from 27 randomised trials : The Lancet

But when you drill down into the data you  discover a mechanism of deception. The benefits reported in the paper applied only to patients whose cholesterol dropped significantly. Looking at all patients in the study who took the statin did not result in decreased death rates. Selecting those whose cholesterol dropped 40 points did show death prevention benefit. They presented risk reduction per unit of cholesterol reduction. From a scientific point of view this is less than honest. The authors simply demonstrated that patients who responded to the drug benefited.

DUH***All previous studies that simply compared patients on statins vs. those not on statins (primary prophylaxis) showed no prevention of death. This is an important distinction, The cost implications of putting low risk individuals on statins are enormous. Statins also rarely can cause death (from rhabdomyalysis) and frequently caused harm.  One comment about this studies’ conclusions was titled “Statins for all by the age of 50 years?” That frightens me.

The mechanism of statin drug benefits are likely related to many known potentially beneficial physiologic effects, not from a reduction of cholesterol. As you will learn in future posts, cholesterol reduction in and of itself is almost meaningless. The amount of circulating cholesterol in your blood is not the problem. The problem is much more complex and relates in part to the oxidation of LDL particles, which has little to do with the amount of cholesterol carried in those particles. Other important factors include systemic inflammation and the response of the innate immune system to factors such as circulating LPS which in turn reflects intestinal permeability. I apologize for the sudden onslaught of abbreviations and medical terms but stay tuned and you will learn what they all mean.

Finally, in the secondary prophylaxis group, the benefits of statin drug use are equivalent to the benefits achieved with exercise-based cardiac rehabilitation following a heart attack. Cardiac rehab offers many benefits in addition to saving lives, produces no significant negative side effects, and improves quality of life and sense of well-being. Many patients on statins feel lousy.

Efficacy of exercise-based cardiac rehabilitation… [Am Heart J. 2011] – PubMed – NCBI

In my next post I will discuss saturated fat  and coronary artery disease. This issue represents the crux of controversy in the heart-healthy diet debate which most physicians and the AHA consider clarified (eat less saturated fat). You already know generally what I have to say about that if you have read my Manifesto page. The next post will expand on the saturated fat section in the Manifesto. Subsequent posts will discuss cholesterol, LDL cholesterol, LDL particle number, oxidized LDL and glycated LDL (the last two are referred to as modified LDL)

Bob Hansen MD

2 thoughts on “Number Needed to Treat (NNT) website and Statin Drugs

  1. Julie henderson

    My brother was diagnosed with chronic fatigue. Last week his new primary care physician took him off of statins. He’s starting to feel better already.

    Reply
  2. Greg Bouska

    This is great reading and very informative. I can’t wait for your next blog article. Just about every physician I know about 4 years ago was spouting off about the benefits of statin therapy and I would ask about the increased risk of diabetes and there was silence. Thank you Bob,
    Greg Bouska MD

    Reply

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s