Taking A Break

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Osteoporosis Drugs Contribute To The Fractures They Were Intended To Prevent

Fosamax, a drug prescribed to treat osteoporosis, was in the news recently:
Merck Loses $8 Million Verdict In Trial Over Fosamax, Bloomberg, June 25 2010

When one woman receives damages of $8 million, "$3 million more than the $5 million her lawyers had asked for," because a jury "found that Fosamax is defectively designed and unreasonably dangerous," it made me wonder how these drugs work. What about them makes them dangerous when taken as prescribed?

Here's what I discovered:

Fosamax is a drug used to treat osteoporosis and other bone diseases. Merck received FDA approval for it in 1995 and held the patent until 2008 when a cheaper generic version, alendronate, became available.

Fosamax is in a class of drugs called bisphosphonates. These drugs slow the normal dismantling of bone by cells called osteoclasts. Normal healthy bone is in a constant state of turnover, broken down by osteoclasts and reformed by osteoblasts. Bisphosphonates cause osteoclasts to destroy themselves.

Slowing the breakdown of bone seems good. But turnover is necessary so bones can remodel themselves, for example, for growth or to repair tiny fractures incurred through daily use.

One area of frequent daily use is the jaw. The jaw bone is also vulnerable because it's close to bacteria in the mouth, "teeth are separated from bone by no more than 2 mm of periodontal connective tissue ... infections have easy access to underlying bone."¹

Jaws also experience trauma during dental procedures. In fact, the majority of cases of jaw death in people taking bisphosphonates occurs after tooth extraction or other dental surgery.¹ Such assaults require repair by our body, an activity that's diminished in people taking Fosamax. (In photo, the area experiencing jaw death is the bit of yellow-white ragged exposed bone on the right.)

In the lawsuit above, Shirley Boles sued Merck claiming parts of her jaw bone died from taking Fosamax. The jury agreed.

The Jaw Isn't All

When you suppress bone turnover, which bisphosphonates like Fosamax, Actonel, and Boniva do, small stress fractures aren't easily repaired. They persist and accumulate. The bone can still take up minerals, although this produces a hard, brittle bone over time. When there is even slight trauma to brittle bone that has amassed small fractures, there is opportunity for severe damage.

Here's a short video describing the case of Sandy Potter, 59, who broke her thigh bone jumping rope, and the case of Sue Heller, 60, who broke both thigh bones from just walking:



One of the most disturbing aspects of these drugs is how long they stay in the body. The estimated half-life for Fosamax (alendronate) is up to 12 years.¹ If you're planning dental surgery, it may not be enough to stop taking them for a few weeks before and after, especially if you've been taking them for several years or if you take them intravenously.

One of the best things you can do to protect bone is to use it. Walk, stretch, lift weights. Another is to limit the amount of acid-producing foods you eat, or balance them with alkaline-producers. Acid-producing diets may leech minerals from bone to neutralize that acid. A diet that emphasizes fruits and vegetables and that minimizes meat and dairy foods is a low-acid-forming diet.
________¹ Systematic Review: Bisphosphonates and Osteonecrosis of the Jaws, Annals of Internal Medicine, 2006
Photo of knees from the article that accompanied the video: Fosamax: Is Long Term Use of Bone Strengthening Drug Linked to Fractures? Popular Class of Osteoporosis Drugs May Have Opposite Effect For Some Women, Experts Say, ABCNews, March 2010
Photo of jaw bone from first reference.

Calcium: Prostate Cancer, Now Heart Disease

A new study is reporting that calcium supplements are associated with an increased risk for heart attack:

Effect Of Calcium Supplements On Risk Of Myocardial Infarction And Cardiovascular Events: Meta-Analysis, British Medical Journal, July 29, 2010

The study is a meta-analysis, not an original trial but a study of studies, in this case 15 prior studies (about 12,000 participants). Participants took supplements containing at least 500mg calcium/day.

Findings (Click to enlarge):



Conclusion:

"Calcium supplements (without coadministered vitamin D) are associated with an increased risk of myocardial infarction. As calcium supplements are widely used these modest increases in risk of cardiovascular disease might translate into a large burden of disease in the population. A reassessment of the role of calcium supplements in the management of osteoporosis is warranted."

There was about a 30% increased risk for heart attack; the range went up to 70%.

Calcium And Prostate Cancer

Readers of this blog know that there is a strong association between calcium intake (both from supplements and from food, especially dairy products) and prostate cancer, that is, calcium increases cancer risk. For example:

"In summary, there is reasonable evidence that both vitamin D metabolites and calcium, and specifically calcium from dairy sources, play important roles in the development of prostate cancer."
- Dairy Products, Calcium, and Vitamin D and Risk of Prostate Cancer, Epidemiologic Reviews, 2001

Calcium Decreases Vitamin D

Various outlets are reporting that the increased risk for heart attacks is owing to calcium's possible role in increased vascular calcification, that is, hardening of the arteries. But again, readers of this blog know that calcium suppresses production of vitamin D in our body, and that might not be a good thing. (See also: Vitamin D: The Active Form, And The Role Of Calcium):

"When serum levels of calcium are low, 1, 25 D [this is active vitamin D] acts on the bones, kidneys, and intestines to increase retention and absorption of calcium until serum levels return to a normal range. Similarly, if serum levels of calcium are high, production of 1, 25 D is suppressed by reduced parathyroid hormone production."
- Dairy Products, Calcium, and Vitamin D and Risk of Prostate Cancer, Epidemiologic Reviews, 2001

Vitamin D is a hormone which is thought to play a role in, not just bone health, but heart disease, diabetes, hypertension, multiple sclerosis, arthritis, and cancer.

Note that in the study in the previous post about the diets of long-living Okinawans, they consumed only about 500 mg calcium/day, yet they have some of the highest number of centenarians in the world. This is a far cry from the 1000, 1200, 1500 mg/day recommended by various health organizations here.
________Photo of calcium pills: Bix