Christina Applegate says she probably had MS for 7 years before diagnosis

Christina Applegate believes she might have had multiple sclerosis for as long as seven years before officially being diagnosed with the autoimmune disease in 2021.

Battling symptoms on and off, the Emmy winner and "Married ... With Children" alum said she put off being checked by a doctor despite her legs giving out while filming the first season of her Netflix comedy "Dead to Me."

Read more: Christina Applegate mentions illness and jokes 'body not by Ozempic' at the Emmys

"I really just kind of put it off as being tired, or I'm dehydrated, or it's the weather," Applegate said this week in an interview that aired on ABC's "Good Morning America." "And then nothing would happen for, like, months, and I didn't pay attention."

Multiple sclerosis, or MS, affects the nervous system and often results in progressive physical and cognitive decline. It's an autoimmune condition in which the body attacks myelin, the protective tissue that surrounds nerve fibers, disrupting signals to and from the brain, according to the National Multiple Sclerosis Society.

In her first on-camera sitdown since her diagnosis, Applegate was joined by "The Sopranos" alum Jamie-Lynn Sigler, who also has the incurable disease. Sigler, who is launching the "MeSsy" podcast with Applegate on March 19, was diagnosed with MS in 2001 at age 20 but didn't reveal her diagnosis until 2016.

Applegate, 52, and Sigler, 42, opened up about about how they support one another, which they likely will discuss on the podcast.

"For so long, I have been celebrated for being the strong one and the positive one that it felt like I was not that if I would admit that some days were hard," Sigler said. "But [Applegate] really pushed me to be able to say that [it was hard], because I thought I was letting people down if I would talk about how hard it was sometimes."

Nearly 1 million individuals are living with MS in the United States, according to 2019 figures cited by the Multiple Sclerosis Assn. of America. Most people with MS experience their first symptoms and are diagnosed between the ages of 15 and 50 (although individuals of any age may be diagnosed with MS). More women are diagnosed with MS than men, the association said.

Sigler said she's holding on to hope for advancements in treatments for the disease and noted that there are medications available to help slow the progression of MS and decrease the frequency and intensity of symptoms for patients.

"There's this little bit of hope that maybe one day we won't live with this," Sigler said. "It's hard to let that go."

Applegate shared her diagnosis publicly in 2021, not long after she was unable to walk on her own while filming the final season of "Dead to Me." She told Roberts that her symptoms started in early 2021 and presented as "just tingling" in her toes.

Read more: Selma Blair urged Christina Applegate to get tested for MS after clocking this symptom

"By the time we started shooting in the summer of that same year, I was being brought to set in a wheelchair. Like, I couldn't walk that far," Applegate said.

Her friend and "The Sweetest Thing" co-star Selma Blair, who was diagnosed with MS in 2018, urged Applegate to get tested.

"She goes, 'You need to be checked for MS,' and I said, 'No,' I said, 'Really? The odds? The two of us from the same movie. Come on, that's not gonna be — that doesn't happen,'" Applegate said. "She knew. If not for her, it could have been way worse."

Applegate has been open about her health struggles throughout her career, previously discussing her 2008 battle with breast cancer, after which she had a double mastectomy as well as her ovaries and Fallopian tubes removed.

But with MS, she described living in a "kind of hell" and isolating to cope with "the invisible disease," which she said is very lonely and involves excruciating pain. She's "just used to it now."

"I've been playing a character called Christina for 40 years, who I wanted everybody to think I was because it's easier," Applegate said. "But this is, it's kind of my coming-out party. Like, this is ... the person I've been this whole time.

"I was kind of putting on a little act for everybody for so long because I just thought that was easier — be light, be funny ... don't make people uncomfortable. And I don't care anymore."

Although she's grateful for the support she's had, she still faces plenty of challenges.

Read more: Even with MS, Christina Applegate wraps 'Dead to Me' with help from her loving co-star

"I'm never going to wake up and go, ‘This is awesome.’ I’m just going to tell you that. Like, it’s not going to happen,” she said. "I wake up and I’m reminded of it every day. … But I might get to a place where I function a little bit better. Right now I'm isolating, and that’s kind of how I’m dealing with it is by not going anywhere because I don’t want to do it. It’s hard.”

The Tony Award-nominated "Sweet Charity" star said that she doesn't go out much and that even sitting for the "GMA" interview, which took place at a hotel, "is a little difficult, just for my system."

The actor also reflected on the emotional reception during her January appearance at the Primetime Emmy Awards. The "Samantha Who?" star received a standing ovation when she walked onstage using a cane and made jokes about the audience "shaming me with disability by standing up" and her "body not by Ozempic."

Read more: Christina Applegate denounces Candace Owens for mocking disability-inclusive Skims ad

But Applegate said she "actually kind of blacked out" during the presenting gig.

"People said, 'Oh, you were so funny,’ and I’m like, ‘I don’t even know what I said,'" she told Roberts. "I don’t know what I was doing. I got so freaked out that I didn’t even know what was happening anymore. And I felt really beloved, and it was really a beautiful thing.”

Then, with her trademark wit, she said, "That audience stood up for everybody."

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This story originally appeared in Los Angeles Times.