Feb. 15--People with prescriptions to counter the debilitating effects of osteoporosis should not be alarmed by concerns of a very rare jaw condition, Kaiser health researchers say.
It's an advisory that will become even more important as growing numbers of people suffer from deterioration of bone tissue.
People taking the oral medications for osteoporosis have a slightly elevated risk of developing osteonecrosis of the jaw, a rare but serious condition. However, the risk remains extremely low, said Kaiser Permanente investigator Jeffrey Fellows.
Fellows is lead author of the study published online in the Journal of Dental Research.
About 4.7 million people are taking the medications -- oral bisphosphonates -- to counter osteoporosis. The disease is characterized by weakened bone tissue, leading to an increased chance of breaking a bone.
About 44 million people are threatened, and nearly half of all women older than 50 will break a bone because of osteoporosis, according to the National Osteoporosis Foundation.
Osteonecrosis of the jaw occurs when blood flow to the bone is reduced; it's difficult to treat. Most cases have been reported in cancer patients taking intravenous bisphosphonates, according to the Kaiser study.
In this study, researchers wanted to learn more about the use of oral bisphosphonates in a large, defined population. Some familiar brand names include Boniva and Fosamax.
"The study came about because there was a lot of fear about it, a lot of misinformation," Fellows said. "Conclusions were being drawn that osteonecrosis of the jaw was solely caused by bisphosphonates."
Researchers looked at electronic medical records of 572,606 patients from 1995-2006.
"We saw a lot of documented discussion between patients and their doctors about osteonecrosis of the jaw, even though the patients didn't have it," Fellows said.
Those patients didn't want the medication and told their doctors they wanted something else, Fellows said.
"There were frank discussions about it, how their health was at risk if they stopped taking it," he said.
Of the patients whose records were reviewed, 21,164 were prescribed oral bisphosphonates; six of them developed the disease of the jaw.
Compared with the overall population, patients taking oral bisphosphonates were nine times more likely to develop the jaw condition than those who didn't take the medication.
"There was lot of good news, and some caution in there. The good news is that the drug is extremely effective, and it's important that people continue to take it" to maintain bone strength, Fellows said.
"The cautionary tale is that even though the number of incidents is small, there is a little higher risk" for medication users, he said.
There are a couple of ways the drugs can counter osteoporosis, Fellows said.
"We cycle through layers of bone like we do layers of skin. For osteoporosis patients, the process is disrupted," he said. "Some stop the shedding, so the outer layers are not dissolved. The other way works from the inside, to build in the structure of the cells themselves."
By 2025, there will be more than 3 million fractures a year related to osteoporosis, with related costs of about $25 billion, according to the National Osteoporosis Foundation.
The study was supported by grants from the National Institutes of Health.
-----
To see more of The Columbian, or to subscribe to the newspaper, go to http://www.columbian.com.
Copyright (c) 2011, The Columbian, Vancouver, Wash.
Distributed by McClatchy-Tribune Information Services.
For more information about the content services offered by McClatchy-Tribune Information Services (MCT), visit www.mctinfoservices.com.