Statins vs Breast Cancer

We’ve written about both of these topics (statins and breast cancer) before, but this is the first time we’re talking about the effect of one on the other.

So, first of all, let’s recap a little: statins, often prescribed to lower cholesterol levels, are:

• often (but not always) much less effective for women than for men, and also
• often (but not always) come with side effects that are typically a lot more serious for women than for men.

The side effects can then lead to a “side effect train” whereby the patient then has to take something else to treat the side effect, then something else to treat the side effect(s) of that medication, and so on, until they are taking an increasingly large stack of medications. See also: Are You Taking PIMs? Getting Off The Overmedication Train

Based on that, statins will not be “the right choice” for women as often as they are for men.

You can read on that in detail, here: Statins: His & Hers?

Or if you want to get really into detail, then check out this excellent book that we reviewed (and whose information largely informed the above-linked article): The Truth About Statins – by Dr. Barbara H. Roberts

And to borrow from that article:

❝Statins do have their place, especially for men. They can, however, mask underlying problems that need treatment—which becomes counterproductive.

When it comes to women, statins are—in broad terms—statistically not as good. They are a little more likely to be helpful specifically in cases of atherosclerosis, whereby they have a 50/50 chance of helping.

For women in particular, it may be worthwhile looking into alternative non-statin drugs, and, for everyone: diet and exercise.❞

As for those non-statin alternatives, actually drugs (in the sense usually meant) are not the only option either, as there are natural compounds that have been shown to help, for example:

Policosanol: A Rival To Statins, Without The Side Effects?

…and:

Take These To Lower Cholesterol! (Statin Alternatives)

In statins’ favor…

Researchers (Dr. Alana Cavadino et al.) investigated the relationship between statins and breast cancer mortality.

This is highly relevant, because breast cancer is the most common and deadliest cancer in women; older women are at higher risk and often take statins for cardiovascular health. It’s not just a matter of “statins improve heart health and therefore indirectly improve breast cancer survivorship rates as part of decreasing all-cause mortality”, but rather, statins inhibit an enzyme overexpressed in breast cancer and influence cell proliferation, apoptosis, and immune responses.

Metabolic function in general is also important for breast cancer survivorship, though: What Your Metabolism Says About How Aggressive Breast Cancer Is Likely To Be For You

…which is why we also covered The Exercises That Help Keep Breast Cancer At Bay!

Now, previous studies linked statins to lower breast cancer recurrence and death, but may have been biased by factors like immortal time bias (ITB)*, cancer stage, estrogen receptor (ER) status, timing of statin use, and statin type.

*ITB = when survival time is misattributed to a treatment period before a patient actually starts treatment, potentially inflating the perceived benefit.

So, clearly more research was needed! Which is something, by the way, the authors of the aforementioned previous studies also acknowledged—towards the end of almost any decent scientific paper you will usually see two things:

• a list of limitations of the study that was just done (i.e., mentioning the possibility of the above data biases, for example)
• a suggestion (often a tacit plea) for more research in the area, often with examples of what things in particular they’d like to see done

Science is very collaborative like that; there is so much to be done that the only way forward is to share the work done, and not merely pass on the baton, but usually pass on several batons (new lines of research) while still continuing one’s own.

In this case, rather than taking to the lab and getting out the test tubes, the researchers opted for a meta-analysis, which basically means going through everyone else’s research with a fine-toothed comb, pooling data from a large number of studies, and doing some advanced mathematics to determine what conclusions can be made from the data available as a whole.

Think of it like a shell game: if a person hides a pea under one of a set of 3 inverted cups and shuffles them, and then you check under the cup, and the pea’s not there, then you know it’s under one of the other two. If someone else (who hasn’t seen what you saw) is able to look under another cup, and finds the pea is not there either, then they also know it’s under one of the other two that they didn’t check. Alone, you each have a 50% chance of being right about which cup the pea is under, but if you combine your knowledge, you now know more than either of you could have calculated alone.

So, that’s what a meta-analysis does, only it was 34 other separate teams of people most of whom didn’t talk to each other while looking under a combined total of 689,990 cups for the same pea.

With that in mind, some notes:

• What was included: this meta-analysis included 34 studies and 689,990 women with breast cancer; outcomes studied were breast cancer death (21 studies) and recurrence (20 studies) ← notice there is a small overlap because some studied both
• What the data was like: most studies adjusted for age, cancer stage, and other conditions, but only half adjusted for medication use. Follow-ups ranged from under 5 years to 10 years. Five studies were prospective.
• What statins were used and when: 14 studies differentiated between lipophilic and hydrophilic statins (this will be important later); 27 studies looked at post-diagnosis statin use, while others looked at pre-diagnosis or both.

What they found:

• About mortality: statin use was linked to a 20% reduction in breast cancer death risk; lipophilic statins had a stronger protective effect.
• About recurrence: statins were associated with a 24% reduction in recurrence risk; stronger effects seen in ER-positive patients (that is: patients in whom the cancer was made worse by estrogen, because the cancerous cells had estrogen receptors)

With regard to that concern about the potential data biases in the studies: small studies reported larger benefits, but analyses showed results remained valid even after correcting for publication bias.

You can read the paper in full, here: Statin use and breast cancer-specific mortality and recurrence: a systematic review and meta-analysis including the role of immortal time bias and tumour characteristics

Want to learn more?

Check out:

How To Triple Your Breast Cancer Survival Chances, and especially 8 Signs On Your Breast You Shouldn’t Ignore

For those curious about the hormonal side of things, you might consider: The Hormone Therapy That Reduces Breast Cancer Risk & More

And if you want to go deeply into it, then:

The Smart Woman’s Guide to Breast Cancer – by Dr. Jenn Simmons

…is an excellent book on the topic.

Take care!