Los Angeles Times. 'Dead to Me' star Christina Applegate ventures a guess at what might be causing her symptoms that led to her MS misdiagnosis: poisoning. Weeks after revealing she was misdiagnosed with MS, the actress questioned whether aging breast implants have been "poisoning" her. Christina Applegate has voiced her fears that her breast implants may have caused her debilitating health issues. With Children alum revealed that she had been.