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Sara S
11-03-2012, 08:30 AM
from delancyplace.com:

In today's selection - the bedrock of measuring medical advances is controlled scientific
tests, especially the randomized controlled tests (RCTs) that have become prevalent
within the medical industry. However, all too often, the complexity and difficulty
of this type of testing yields varied and contradictory results:

"Flip-flops: All of us are familiar with and frustrated by the radical shifts in
opinion that come from clashing RCTs and dueling meta-analyses. ... The ... flip-flops
are not course corrections. They are neck-snapping 180-degree hairpin turns that
morph today's truths into tomorrow's taboos and yesterday's wisdom into today's
witchcraft. Is it any wonder that compliance suffers and recommendations go unheeded?
Who can really blame parents who refuse to vaccinate their children, however much
we disagree? Doctors lose the credibility and trust that is our sole currency.

"Echinacea for colds? Thumbs down in 2002 and again in 2005. But a big thumbs up
in 2007. The year 2010, however, brought another study and more confusion. The
effects of echinacea did not reach significance but 'the trends were in the direction
of benefit. . . data are also insufficient to exclude the possibility of a clinically
significant effect.' The direction of benefit? Insufficient to exclude the possibility?
This isn't science. It certainly isn't medicine. My homeowner's policy has clearer
language than this. I hope that answers the question for you. It doesn't for me.

"Okay, thanks! Two things can be learned from this. There is no scientific design
that will ever answer this question. And second, the press reported this study as
definitive. The evening national network news hailed it as the last word. Think
so?

"Seven hundred thousand coronary artery bypass grafts (CABG) are per*formed each
year. In 2008 the use of an ACE inhibitor (an anti-hyperten*sive agent) preoperatively
was strongly recommended to improve CABG survival rates. In 2009, not only was it
a bad idea, it increased deaths after CABG surgery.

"That aspirin you took to prevent heart attacks? You took them for years. Many of
you still do. Well, they're not on the menu any longer. We've been advised to abandon
their use -- they're too dangerous. Similarly, all of us urged our patients to take
folic acid for primary prevention against coronary artery disease. In 2009 it turns
out that folic acid offers a 38 percent greater chance of dying from cancer.

"Do oral bisphosphonates for osteoporosis cause esophageal cancer? 'No!' say the
authors of an August 2010 JAMA article. 'Yes' say the au*thors of a September 2010
BMJ study. What a difference a month makes.

"Mammogram anyone? If you're between forty and forty-nine years old there is not
a single practitioner who will be able to make sense of the last twenty years of
conflicting advice in making a recommendation. For those over eighty we thought
we finally had sound advice -- no mammograms. Yet the majority of physicians order
them anyway, awaiting the next RCT and avoiding the next lawsuit. In 2009, decades
of evidence was turned on its head as women ran for the exits in confusion and in
anger. It's still best to ask your doctor. ...

"Speaking about breasts, I bet a lot of you still perform self-examinations. You
remember you were told it was important. Well, now we tell you 'Don't touch them,
for God's sake. You're forcing us to do too many un*necessary biopsies!'

"Decades of evidence told diabetics to keep tight control of their blood sugars
to avoid heart attacks, strokes, blindness, kidney failure, and ampu*tations. Millions
of lives were made miserable trying to balance blood sugar levels on the head of
a pin. All in vain. A 2010 review of thousands of dia*betics showed that this practice
was not helpful for most clinical endpoints and, in fact, caused more complications
than 'usual care.' Please don't get me started on PSAs (prostate-specific antigen
tests). ...

" 'On Second Thought': Not only do RCTs clash with each other, some*times there
are multiple interpretations of one RCT. These 'on second thought' analyses can
occur years after the facts were assumed to be in. The Women's Health Initiative
(WHI), one of the largest RCTs ever performed, found that hormone replacement therapy
(HRT) increased morbidity and mortality for heart attacks, strokes, Alzheimer's
disease, breast and ovarian cancer, and deep vein thrombosis. The investigation
was carried out by the most respected physicians, statisticians, and epidemiologists.
The findings appeared in the most rigorous scientific medical journals. So compelling
were the findings and the dangers of therapy, two WHI trials were halted midway
out of ethical considerations (although a bit grudgingly). The use of HRT for cancer
prevention and postmenopausal symptoms plummeted. Here we are seven years later
and it turns out the findings were weak and not statistically significant. The conclusions
were described as 'distorted,' 'oversimplified,' and just plain wrong. It was all
just a 'false alarm.' "

Author: Steven Z. Kussin, M.D.
Title: Doctor, Your Patient Will See You Now
Publisher: Rowman & Littlefield
Date: Copyright 2011 by Rowman & Littlefield Publishers. Inc.
Pages: 7-9
Doctor, Your Patient Will See You Now: Gaining the Upper Hand in Your Medical Care
by Steven Z. Kussin by Rowman & Littlefield Publishers
Hardcover
If you wish to read further: Buy Now [https://r20.rs6.net/tn.jsp?e=0012KQCnQHmy5GxBAARSKOPafUh2zF0adPrAeI-R87PGQupcsB1nu-4o_yRJXcsgNG8tc5piR_RCMLxbycwnAXwdB2HlamHWt9oxDffrH7vx5eZ4UaIFZhOXFfFA8USTmeYnuS9PFoCvtVdYkmQe18qQXDq-UTziojkV2djIi5jklCx6w9ccfbdm_bsjju6C75R13mbBjtT_8t4m9lJ3vMMaZLpGAqzJNxMYJVQn_UZEkNmVAdF55SHLbv2qjz_r2sJmNd8PsN_ZJsdRCdckoM9RjMv7t2HjtqsGwXcZ0D7Nj8j2J3 Hp6tIYwNX98_h_ldQrXBUH7WxmzVjnO_00SQca1iAt2x3c1_sqzYTd4husvpYAfskUivvcdaDyVQU6a3O14Z2Fh78HCo=]
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