Our understanding of Alzheimer’s disease is better than ever before. So why are we still so far from a cure?
When Chris Riley said goodnight to her mother Diane on the phone one chilly February evening in 2013, she had no idea that both their lives were about to change forever.
She didn’t know that shortly after midnight, her mother would wander out of the house into the freezing Michigan air with only a light jacket and inadequate footwear.
Fortunately for Diane, clarity briefly returned several blocks away and she rang a neighbor’s doorbell for help.
Unable to properly explain who she was or why she was lost, she showed the neighbor a piece of mail in her pocket with her name and address on it. Although Diane walked away again, the quick-thinking neighbor called the police, who were able to find the older woman within 20 minutes and return her to the safety of her home.
“When my mom wandered, we knew immediately we had to place her inside a care facility,” Chris told Healthline. “She was a very independent person. Putting her in a facility broke my sister’s heart, broke my mom’s heart. It was the hardest thing we’d ever done.”
Diane had a dual diagnosis of frontotemporal dementia and early-onset Alzheimer’s disease. Her episode of wandering proved to be the beginning of the end. She ultimately passed away in early 2014 at the age of 73.
Her case is only one of millions.
As medicine improves and lifespans grow longer, bringing the baby boomers into the age range where Alzheimer’s usually appears, these numbers are expected to grow astronomically.
By 2020, only 2 percent of Medicare spending will go to baby boomers with Alzheimer’s disease. By 2040, that number will be almost 25 percent, with more than 28 million boomers suffering from Alzheimer’s disease.
Without new treatments or cures, these numbers could overwhelm the U.S. healthcare industry.
Last week’s Alzheimer’s Association International Conference (AAIC) presented a wealth of new research and understanding about Alzheimer’s disease, raising the hopes of many that a cure might soon be within reach.
But how optimistic should patients, caregivers, and family members be?
Healthline reached out to Alzheimer’s experts to learn more.
To figure out how to treat and prevent Alzheimer’s disease, scientists first have to learn what causes the condition.
Although there’s a growing wealth of data on the topic, it hasn’t been enough to present a single, cohesive picture.
“I think cloudy and piecemeal actually is a fairly good description of where the field’s understanding of Alzheimer’s disease [is],” said Dr. Keith Fargo, director of scientific programs and outreach at the Alzheimer’s Association, in an interview with Healthline.
“You look at HIV, and that’s something where it’s a virus, and we know the virus that causes AIDS,” explained Fargo. “And so that’s something very simple to link onto and research. With Alzheimer’s disease, that’s not the case. It’s probably going to be very multi-factorial.”
Much of the research is currently focusing on amyloid and tau proteins, whose malformation are classic characteristics of Alzheimer’s disease. But Fargo says other factors likely also play a role, including vascular health, inflammation, lifestyle, and possibly even viral causes.
“So say a 78-year-old woman [presents] with the syndrome of dementia with memory problems. At that age, she probably has three, four, or five of these components present in her brain,” explained Dr. Ronald Petersen, director of the Mayo Clinic Alzheimer’s Disease Research Center and the Mayo Clinic Study of Aging, told Healthline. “So it’s not likely that there’s going to be a single avenue that tells us ‘this is the way to treat Alzheimer’s disease or treat the syndrome.’ It’s probably going to take a combination of therapies and a cocktail of drugs like we do for other disorders.”
Age, Fargo says, is the number-one culprit.
“The older you get, the more and more likely you are to develop Alzheimer’s disease,” he said. “That being said, Alzheimer’s disease is not normal aging. Most people experience some kind of cognitive decline as they get older, so that’s not Alzheimer’s disease. Alzheimer’s disease is a universally fatal disease of the brain that actually causes neurons to die over the course of time until the person ultimately passes away from the Alzheimer’s pathology. So it’s similar to cancer in that the older you get the more likely you are to develop cancer, but cancer is not normal aging.”
And even the two starring proteins, amyloid and tau, are laden with mystery.
They are more likely to malfunction with increasing age, and certain genetic mutations have been linked to their deformation in a percentage of patients. But the root cause of what prompts them to begin malfunctioning in the first place remains unknown.
Because Alzheimer’s disease has a wide array of causes, symptoms can vary tremendously from person to person.
For Diane, one unexpected symptom was hallucinations. She began seeing visions of her husband (who died in 2004) and seeing images of her two daughters as young children.
“Alzheimer’s presents itself differently in every single person,” said Chris Riley. “There’s some very general things that can happen, but when people have Alzheimer’s, each person’s experience is unique to themselves.”
This makes a clinical diagnosis, or a diagnosis off the basis of symptoms, tricky.
“The clinical diagnosis of Alzheimer’s disease by a physician due to his [or her] experience in the area is usually right but not always,” said Dr. Victor Henderson, professor of health research and policy and of neurology and neurological sciences at Stanford University, and director of the Stanford Alzheimer’s Disease Research Center, in an interview with Healthline. “Maybe 90 percent of the time the clinical diagnosis is accurate, a little bit less where there are atypical features.”
In 2011, the National Institute on Aging developed a report with new guidelines for diagnosis. It incorporated a wealth of new research, including a number of tests that look at biomarkers in the body to diagnose Alzheimer’s disease.
For a rare few, a genetic test can reveal whether the person is likely to develop early-onset Alzheimer’s, a particularly swift-moving version of the disease.
Meanwhile, people suspected of having Alzheimer’s can undergo a PET scan to look for abnormal amyloid or tau proteins in their brain. These proteins can also be measured in the person’s spinal fluid.
“Through a combination of these different spinal fluids and imaging tests one can be a bit more certain about the diagnosis, [and] even these aren’t 100 percent,” said Henderson.
These tests are also not currently covered by Medicaid, Medicare, or by most private health insurance companies. Although the tests may improve diagnosis rates, there isn’t yet evidence to show that this improved rate will actually result in improved outcomes for patients.
Fargo plans to address this with a study that he and the Alzheimer’s Association are working on: Imaging Dementia, Evidence for Amyloid Scanning (IDEAS). Funded with $100 million and examining almost 18,500 people, he hopes to demonstrate that amyloid scans do in fact improve patient outcomes. He expects the results will be ready sometime in 2019.
Once Alzheimer’s disease has been detected, the next step is treatment. And the picture there isn’t much brighter.
The best goal, of course, would be to prevent Alzheimer’s disease from occurring in patients at all. And there, lifestyle may play a role.
“We know things like good diet, exercise, maintaining cognitive activity, and social activity can slow down or delay cognitive decline,” said Fargo. “That’s fairly clear. What we don’t know yet is whether that’s going to delay the onset of frank dementia symptoms.”
A clinical trial in Finland called the Finnish Geriatric Intervention Study to Prevent Cognitive Impairment and Disability (FinGer) hopes to answer this question. It has 1,200 participants, half of whom are receiving normal medical treatment and half of whom are receiving extra preventative care. This includes a special diet and structured exercise, social, and cognitive activities. The study will follow participants for nine years to see if these interventions make any difference.
In addition, a number of medications have entered clinical trials that are designed to slow or prevent the onset of Alzheimer’s disease. So far, not a single one has proven to work, says Fargo, although new ones are constantly entering new rounds of clinical trials.
Meanwhile, for people who are already experiencing Alzheimer’s disease, prospects aren’t much better. There are some existing medications on the market, such as Aricept (donepezil) and Namenda (memantine).
Even these aren’t what they need to be, says Fargo.
“The currently available drugs have been shown to have symptomatic benefit,” he explained. “They are inadequate, but it’s important that we have them, they do good for a lot of people, but they are inadequate in the sense that they only work for some people, not all people, and they only work for a period of time. After they stop working, most people’s cognition then falls back to the same level it would have been had they never taken their medication to begin with.”
Part of what has been throttling Alzheimer’s disease research progress is a lack of funding.
In 2010, Congress unanimously passed the National Alzheimer’s Project Act, which declared the goal of preventing or effectively treating Alzheimer’s disease by 2025.
To accomplish this, funding has ramped up. The NIH is projected to fund $586 million of research in 2015. However, this will fall far short of the $2 billion annually that is projected to be needed over the next 10 years in order to meet the 2025 goal.
“Half a billion sounds like a lot of money, but if you put that into perspective and look at other diseases such as cancer and heart disease, some of the other major killers, it’s very little actually,” said Fargo. “Compared to funding in those areas, which tend to be funded in the area of 2 to 4 or even 6 billion dollars per year, and that’s why you see progress being made by scientists in those disease areas.”
Legislation is currently in both the House and Senate to add an additional $300 million in funding.
“It’s great, but it still puts us under one billion a year, which is half of what the scientific community is telling us,” said Fargo. “So it’s a huge step forward, a major leap in the right direction, but we still need to do more.”
Other ways that people can help are to participate in the Walk to End Alzheimer’s and to get involved with their local Alzheimer’s Association chapter.
And, perhaps most crucially, to enroll in clinical trials.
“A big barrier right now is recruitment for clinical trials,” said Petersen. “That is, getting people to volunteer to participate in these clinical trials, because unless we try out these different therapies and medicines, we’re not going to know which one works. It takes years sometimes to recruit for a full trial. It requires a hundred or a thousand patients, and that can be devastatingly slow to the drug discovery process.”
These trials aren’t just looking for people who already have Alzheimer’s disease.
“There are trials going on now for people with just a little bit of memory impairment,” explained Petersen. “There’s even a trial going on for people who are cognitively normal but may harbor some of the biologic characteristics of Alzheimer’s disease, and those trials are recruiting, so just be mindful that there’s an opportunity for everyone to participate in this effort.”
Fargo adds that there are also trials for completely healthy people and even trials for supporting caregivers of people with Alzheimer’s disease. He suggests interested people go to TrialMatch, which can help match qualified participants with a trial that needs their help.
Chris has thought about enrolling in such a trial, but at the end of the day, she has to look out for her own well-being first.
“Having seen the really bad part of Alzheimer’s, that’s where the progression is going to go,” she said. “Since my mom’s death, that level of stress is gone. I don’t want to bring on the stress of thinking about it all over again. That’s just not something I want to consider for my life, even if I were to help science. There’s a part of me that is interested in helping out and doing that, but I would be thinking about it all the time. It’s not like I could just be part of the clinical trial, and compartmentalize it. It would eat into everything. If my mom were alive, it might be different.”
Instead, Chris is contributing to the community in other ways. She performs outreach and engagement for a documentary about Alzheimer’s disease, “The Genius of Marian,” and is working on a partner website for caregivers, The Genius of Caring.
“With the screenings and with the site, our goal is to help connect people, so people don’t feel so isolated, and help break the stigma of Alzheimer’s,” she said. “It’s nice to hear how someone else has dealt with a similar situation.”
Even though funding isn’t what it needs to be, Alzheimer’s disease research is still picking up its pace.
“If you had asked me this even two years ago, I would not be hopeful,” said Chris. “Seeing all of what’s happening, I’m actually pretty hopeful.”
Henderson shares her optimism, albeit more guardedly.
“Fifteen years ago, I thought we wouldn’t be having this conversation today,” he said. “I thought that enough was beginning to [be] known about the disease [and there would’ve been] important breakthroughs that would make a tremendous difference right now. And that hasn’t happened. It’s turned out that the disease is more complicated than people thought and those breakthroughs aren’t there. I am optimistic that something important, clinically relevant, is going to happen, but I’m not able to say that it’s right around the corner.”
He concluded, “It may be that it won’t be one major breakthrough, it’ll be a lot of more modest breakthroughs and the eventual treatment will consist of several different approaches, each of which has a modest effect, but in aggregate, there’s an important large effect. So I am optimistic, but I don’t see this as right around the corner, I see this as a large concerted effort and sooner or later it’s got to work.”