However, her regimen of aerobics, weight lifting and swimming is especially impressive because two years ago she was almost immobilized by her rheumatoid arthritis.
"I had to actually crawl on my hands and one knee and drag this leg behind for a couple of days," says Petersen. "It was excruciating pain to try and stand on it."
In 36 years with the disease, she tried many drugs. Some helped for a while, but all had to be stopped because of side effects. Since she started the experimental drug Enbrel she says she has a new lease on life.
"I really felt as if I had been released from prison," says Petersen.
In rheumatoid arthritis, a person's immune system goes haywire -- it sends out proteins that cause joints to become inflamed and produce enzymes that destroy cartilage and bone. Enbrel neutralizes those proteins so they can't cause inflammation.
"Patients have fewer swollen joints, they have fewer painful joints, they feel better," says rheumatologist Dr. Eric Ruderman.
Ruderman found Enbrel to be at least as effective as current drugs that treat arthritis, but without the side effects.
"This is a designer drug if you will, that's aimed at blocking a very specific chemical process that goes on in the joints of patients with rheumatoid arthritis...it's a whole new way of treating it," says Ruderman.
It is hoped that if a drug like Enbrel could be prescribed early, it may prevent much of the destruction that occurs over the years.
There is nothing yet that will cure rheumatoid arthritis, or even begin to reverse and repair the damage it causes. However, this drug -- and others under development and pending approval -- will make it easier for people to live with a disease they'll have for a lifetime.
Reported by John Roberts
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