Is Alzheimer's disease the next frontier for precision medicine?

Precision medicine — the ability to target treatments to an individual patient’s disease — has revolutionized cancer treatment.

David Wolk, a neurologist who is codirector of the Penn Memory Center, thinks a similar approach is the “next frontier” in Alzheimer’s disease, the deadly memory disorder that still has no effective treatment for slowing the disease process, let alone curing it.  New research is revealing just how complex and diverse dementia is in terms of symptoms, underlying pathology, and genetics.  This variability may help explain why so many drug trials have failed, but also explains the hope that more precise medications will work for different groups of dementia patients.

Wolk spoke Monday at a daylong conference for professional and family caregivers sponsored by the Alzheimer’s Association Delaware Valley Chapter.  It drew an overwhelmingly female crowd of about 400 to the Valley Forge Casino Resort, where speakers discussed science, the nitty-gritty of caregiving, and the psychological impact of caring for a person who has been changed by a disease but whose essential humanity can still surprise and nourish.

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David Wolk is a neurologist and co-director of the Penn Memory Center.

Dementia is an umbrella term that includes Alzheimer’s as well as other cognitive disorders of aging such as Lewy body, frontotemporal, and vascular dementias. It once could be definitively diagnosed only by autopsy, when pathologists looked for brain changes or specific proteins that are signs of disease.  The diagnosis of Alzheimer’s rests on finding errant forms of amyloid and tau.  Even at specialized centers like Penn’s, doctors were correct only 70 percent of the time when they thought dementia patients had Alzheimer’s.  About 20 percent of the time, a patient they thought had another form of dementia actually had Alzheimer’s.

Now doctors can make much more accurate diagnoses in live patients by using imaging to evaluate the structure of the brain — some parts shrink in Alzheimer’s — and see amyloid and tau.  Other “biomarkers” — such as levels of proteins in spinal fluid — can also help.

Wolk illustrated the diagnostic challenges by describing two patients in their 60s who both came to him complaining of cognitive changes.  One was having trouble with memory; he couldn’t learn a new computer system at work.  But his attention and language skills were fine.  The other was functioning without major problems.  She had detailed recall of current events.  But she was having trouble finding words when she spoke.

Brain scans showed that the man had shrinkage in the hippocampus, or memory center, a classic sign of Alzheimer’s.  The woman had normal brain volume, but there was decreased activity in the back of her brain, another possible sign of Alzheimer’s.  That, combined with deposits of amyloid, showed that she, too, had Alzheimer’s.

Wolk said that Alzheimer’s patients don’t just have different symptoms.  Recent research has revealed more than 20 genes that increase risk in small ways that may offer different drug targets. Plus, most Alzheimer’s patients also have vascular dementia or other problem proteins, factors that influence which drugs might work and how progress is monitored.

Stephen Post, a psychologist at Stony Brook University School of Medicine who has written about ethics and Alzheimer’s disease, spoke about the value of people with dementia.  He prefers the term deeply forgetful.  He said such people can still be creative as artists.  They appreciate music and poetry.  Even after long periods when it seems they are unable to speak, they can offer surprising insights.  When he asked the crowd how many caregivers had experienced that, most people raised their hands.

“I always tell caregivers: Don’t give in to hypercognitive values,” he said, cautioning against thinking of people with dementia as a husk or shell.  “There’s always a person underneath this communicative breakdown,” he said.

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Rabbi Dayle Friedman, who specializes in working with older people, talked about learning to appreciate what people with dementia can teach us.

While acknowledging how sad it can be to watch a loved one succumb to dementia, Rabbi Dayle Friedman urged caregivers to be open to thinking of dementia as not just a journey of suffering. It can be a powerful teacher. Because of their memory problems, people with dementia can be cut off from both the past and the future. That makes them really good at what many of the rest of us struggle with: living fully in the present. “Many experience unabated capacity for joy and love,” she said.

Learning to accept the changes that dementia brings can help us realize that our loved ones are more than their intellect, their memory, their cognition.  “We learn that we are, too,” she said.  “We learn to value ourselves for our very essence.”