A sometimes hidden toll that Alzheimer's disease can take on the family of someone stricken by the condition is being highlighted in the Oscar-nominated film Still Alice.
Playing a victim of early-onset Alzheimer's, Julianne Moore has been nominated for an Oscar as best actress.
Although Alzheimer's is a growing problem in a global aging population, the early-onset form depicted in the film -- Moore plays a professor of linguistics afflicted at age 50 and the movie highlights the effect it has on her loved ones -- is rare, experts say.
Still, while the majority of the 35 million Alzheimer's sufferers worldwide are 65 or older, a small number -- around 4 percent -- are struck by the early-onset form in their 40s or 50s, says Maria Carrillo, Alzheimer's Association chief science officer who worked as a scientific adviser for the movie.
Around 200,000 people in the U.S. suffer from the early-onset version of the disease, the association says.
In the movie, Moore's Alice suffers from a form known as Dominantly Inherited or Familial Alzheimer's Disease -- thought to be involved in around 2 percent of early-onset cases -- in which a gene mutation results in increases in beta amyloid, which when building up can sometimes trigger a series of pathological changes in the brain, Carrillo explains.
If one parent carries the abnormal gene, a child has a 50 percent chance of inheriting the gene and if it is passed on that child will almost certainly develop some form of dementia, she says.
The Alzheimer's Association put Julianne Moore in touch with some people in the early stages of the disease, including Sandy Oltz, a former surgical nurse from Minnesota who was diagnosed with Alzheimer's after symptoms began appearing in her 40s.
"I was putting things away in the wrong places," Oltz says. "I was forgetting to pick up my son from baseball practice."
Oltz, in Skype video calls and texts with Moore, helped the actress understand what it felt like to have Alzheimer's that strikes when one is in their prime, at the height of a career, robbing them of their identity.
Early-onset Alzheimer's takes a toll on families as well.
"You just find yourself in this suspended state for years because you don't know how to move forward," says Julie Karceski, whose mother Dawn, a registered nurse, began showing sings of dementia in her 50s while Julie was still in undergraduate in college.
Worry over her mother caused Karceski to put off her education for several years.
Now a graduate student at MIT, Karceski says her mother is in a Alzheimer's care facility and has trouble recognizing family members.
The Alzheimer's Association says there are warning signals that might differentiate normal forgetfulness that comes with age and something that should be discussed with a medical professional, including memory loss that unsettles daily life, difficulties in carrying out familiar tasks, a withdrawal from social activities or change in personality.