nos-trum. pronunciation: \nos'-trum\. noun. Etymology: Latin, neuter of noster our, ours.
1. a medicine of secret composition recommended by its preparer but usually without scientific proof of its effectiveness.
2. a usually questionable remedy or scheme.
See here for more discussion.

Tuesday, June 29, 2010

Cholesterol-Lowering Drugs And Prostate Cancer Study: Read The Fine Print.

OK, I ate peanuts because they said it would help my, I don't know.  Should I take statins now?

There is press interest in a new study appearing in the journal Cancer (June 28) about cholesterol drugs helping prostate cancer patients.

The headline, "Study: Statins May Protect Prostate Cancer Patients," is classic for not telling the full story.

Many of you may not care about prostate cancer unless you're an older male, or have the disease, or a loved one with it (or just like learning new stuff), but this post is not about treatment of prostatic cancer.   It's about how the press portrays medical advances, a Nostrums specialty.  It reinforces the message that you have to take the time to read beyond the media's superficial assessment.

The research looked at ~1200 men who underwent radical prostatectomy and assessed their PSA test (prostate-specific antigen) level, comparing those test results between two groups: men who were taking a cholesterol drug (a "statin" called simvastatin) and those who weren't.  Take a look at the actual results of the study, keeping in mind the media article title above.

For Onion Peelers (skip, you can come back if you don't like my take on it)
In total, 236 (18%) men were taking statins. Statin users were diagnosed at lower clinical stages (P = .009) and with lower PSA levels (P = .04). However, statin users tended to have higher biopsy Gleason scores (P = .002). ...statin use was associated with a 30% lower risk of PSA recurrence (hazard ratio HR, 0.70; 95% confidence interval CI, 0.50-0.97; P = .03), which was dose dependent (relative to no statin use; dose equivalentsimvastatin 20 mg: HR, 0.50; 95% CI, 0.27-0.93; P = .03).

A lot of gobbledygook.  Translated into English,
1.  The study deals with only one approach to prostate cancer:  radical prostatectomy.  It says nothing about any other way of dealing with this disease.
2.  Guys on statins got diagnosed earlier, but when the tissue was examined they had more aggressive forms of the cancer (a higher Gleason score means worse cancer).  So maybe the statin just "covered up" the cancer, or even made it more aggressive...who knows?
3.  The study looks at the PSA test (prostate-specific antigen) as a measure of disease activity.  While high PSA correlates with occurrence (or recurrence) of disease, it's not a diagnostic test, it's a screening test.
4.  To see the effect of statins the men had to be on 20 mg per day or more.  Some people take less than this for various reasons, and they didn't experience any benefit.  Even with 20 mg, the data was right at the point where statistical significance appears...i.e., not a knock-down result.

Bottom line...there are a lot of questions to answer here.  Do statins protect prostate cancer patients, as WebMD's journalists indicate?

Not enough info.

Doc D

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