(NEW YORK) -- A few weeks before the 2010 U.S. Open, golf pro Phil Mickelson began to experience severe joint pain. Even his regular practice routine suddenly became difficult to endure.
"I didn't think much of it," said Mickelson. "But I didn't know what it was or what it could be."
But 40-year-old Mickelson still couldn't shake it. He and his family left for a vacation in Hawaii, where Mickelson's aches and pains became so excruciating that he could barely get out of bed, never mind swing a golf club.
"I got really scared," said Mickelson. "I started wondering what it was, and if it was even treatable."
Mickelson immediately went to see a rheumatologist, who diagnosed him with psoriatic arthritis, a chronic, inflammatory arthritis caused by an overactive immune system. Symptoms and signs include stiffness, pain and swelling of joints, reduced physical function and reduced quality of life.
While athletic injuries can predispose people to early osteoarthritis, a degenerative disease of cartilage, there is no study that suggests sports predispose people to psoriatic arthritis, which usually hits those in their 30s and 40s.
Up to 30 percent of people who have psoriatic arthritis have had psoriasis, a common skin disease that causes itchy, dry red patches topped with silvery scales on the skin.
Mickelson said that he had psoriasis about eight years ago, and a dermatologist had treated him for it. After diagnosis, doctors put Mickelson on an individualized treatment program right away. Today, the golfer, who has won four major championships and 38 PGA titles, is back to his practice regimens and workouts.
And on Wednesday, Mickelson launched "On Course With Phil," created in collaboration with Amgen and Pfizer, and the Joint Smart Coalition, which includes the Arthritis Foundation and the National Psoriasis Foundation.
The program is meant to about chronic inflammatory conditions and encourage people to get checked if they have any symptoms.
"This is meant to give people who have similar symptoms the tools and resources that will help them get questions of their own answered," said Mickelson. "I was so lucky, because I got on it right away, so I was able to slow or stop any further damage."
"It's important to get diagnosed early to slow or prevent long-term damage," said Dr. Christopher Ritchlin, a professor of medicine at the University of Rochester School of Medicine, who serves as a consultant to "On the Course With Phil."
Mickelson and Ritchlin stressed that there are thousands of people who go untreated for the debilitating disease they lack information information.
"Psoriatic arthritis is a very variable disease. It tends to involve just a few joints and can wax and wane over time," said Dr. Nortin Hadler, a professor of medicine and microbiology and immunology at Chapel Hill. "Hence, the fashion in which it interferes with function is very individualized."
Ritchlin said that treatments for psoriatic arthritis have greatly improved in the last decade. There are now several ways to manage the illness.
The variety of psoriatic arthritis treatments include non-steroidal inflammatory drugs, oral system therapies and biologic agents, which act closer to the cause of the disease.
Dr. Joan Von Feldt, a professor of medicine at University of Pennsylvania, said that Mickelson's early diagnosis was key to his ability to get back to golf.
"The medicines are so powerful nowadays that Mr. Mickelson should expect to go back to his normal superstar career, with the help of his rheumatologist," said Von Feldt. "I've always been a fan of Phil Mickelson, and so I was thrilled that he would use his misfortune and turn it into an opportunity to help others."
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