Advocates say they are on the verge of new disease-modifying treatment -- the first oral medications that may help slow the progress of the disease. The FDA is scheduled to announce Monday whether it approves the use of the medication Gilenya (fingolimod) for first-line treatment for relapsing MS.
Studies have shown a 54 percent reduction in relapses, according to Calder. But Gilenya carries significant risks to lung function and side effects like macular edema and changes in heart function. Calder said doctors and their patients will have to weigh the risks against benefits.
About seven injectable medications are now used to treat the disease, as well as corticosteroids, symptom management and psycho-social therapy.
Salahi said she has the "relapsing-remitting" form of MS, with periods of inflammation when new symptoms appear or old symptoms suddenly worsen. As the inflammation resolves, symptoms can disappear.
"The most important thing is it's really an unpredictable disease," she said. "Most people do not become severely disabled. Many will have difficulty walking or have balance impairment or fatigue, but they can remain on their feet and be mobile with the use of mobility devices."
"The notion that every person with MS requires a wheelchair is not the case," said Calder.
Salahi said she first knew something was wrong that day in the pool.
She had been working as a model -- the face to the "I Love Virginia" tourism campaign -- and was a make-up artist to high-profile political women like Nancy Pelosi, Lady Bird Johnson and her daughter Linda Robb.
"It was a hot day, but I had grown up in Florida," she said. "I thought I would lay out for a minutes and I started not to feel well. It was almost like a prickly heat in my legs and a tingly feeling. Then I jumped back into the pool and felt all over weakness and pain and pins like your hand was going over nails."
"I am kind of a sensitive person and I didn't want to cry and be afraid, but I was in my prime and they are thinking something's wrong with me," she said.
Salahi insists she is not suffering from anorexia and that earlier photos with a fuller face were taken when she was on corticosteroids for MS.
"I am naturally skinny and when I was diagnosed in my 20s, I became more of a health nut and it wasn't that I was staying thin, I want to maintain my weight as I get older," she said. "All the MS books say that it's easier to deal with symptoms and balance and getting around. That's important to me."
Her biographer agreed.
"What I learned in my investigation of MS is that it is wise to be lean," said Dimond. "She is not anorexic. I lived with her in Virginia and she eats all day -- Hershey's kisses and cookies and last night she had a half chicken and a mound of mashed potatoes. She is lucky, because she has a lean body mass."
Salahi said dealing with the MS after all the publicity surrounding the White House affair was "challenging," especially since MS can lead to sadness and depression.
Salahi said she and her husband raced out before dinner -- pumpkin pie, lentil soup and shrimp -- because she had "maxed out" physically and felt as if she were relapsing. In the excitement of the day, she hadn't eaten.
"It felt heavy to walk and I thought I could make it through, but I had already been there three hours," she said. "There wasn't anything on the menu I wanted to eat.