By Liz Seegert | July 7, 2023
The Centers for Medicare and Medicaid Services recently announced it would pay for the cost of an expensive new treatment for people with mild to moderate Alzheimer’s disease, now that the U.S. Food and Drug Administration has granted full approval to lecanemab (Leqembi). The drug received accelerated approval in January, but there are some serious risks to people taking this medication. The Centers for Medicare and Medicaid Services is requiring beneficiaries to enroll in a user registry so additional safety and efficacy data can be collected.
The June 23 edition of Health Affairs has an excellent analysis of the history of this and other Alzheimer’s drugs, the pressure by Alzheimer’s advocacy groups on the FDA for full authorization and expected next steps. So this might be a good time to take a look at the broader issue of dementia — of which Alzheimer’s disease is but one form — and how understanding the nuances and differences among the major forms of these progressive conditions can help inform your reporting.
Normal aging vs. dementia
Dementia is an umbrella term for a variety of diseases and disorders that cause loss of memory, thinking and functioning serious enough to impact daily life. Dementia is not a normal part of aging. Contrary to some stereotypes, many older people live out their entire lives without developing serious cognitive impairment.
Normal aging may include some age-related memory changes that might show as:
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Occasionally misplacing car keys.
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Struggling to find a word but remembering it later.
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Forgetting the name of an acquaintance.
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Forgetting the most recent events.
However, long-term knowledge, experiences, old memories and languages generally remain intact, according to the Centers for Disease Control and Prevention.
Signs and symptoms of dementia vary widely from person to person. Generally, common symptoms may include:
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Getting lost in familiar places.
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Referring to familiar objects with unusual words or using unusual words to refer to familiar objects.
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Forgetting the name of a close family member or friend.
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Forgetting old memories.
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Being unable to complete tasks independently.
Age, race, ethnicity, family history, poor cardiovascular health and repeated head injuries all increase risk of developing dementia. The Alzheimer’s Association projects that dementia will cost $345 billion in health care costs in 2023, rising to a potential $1 trillion by 2050.
Alzheimer’s disease
The majority (60-70%) of people with dementia worldwide have Alzheimer’s disease, the World Health Organization reports.
Alzheimer’s disease is thought to occur when amyloid plaques and tau tangles form in the brain from abnormal protein buildup. New therapies like Lecanemab and Donanemab have been shown to slow down or eliminate the buildup of plaque in clinical studies but also come with some serious risks and side effects.
“It’s not a cure, but a step in the right direction in terms of a new way of really directly targeting the pathology of the disease and helping people to maintain their independence longer,” said Judith Heidebrink, M.D., M.S., a neurologist and co-lead of the Michigan Alzheimer’s Disease Center in Ann Arbor.
According to the Alzheimer’s Association:
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An estimated one in nine people 65 and older (6.7 million) in the U.S. currently live with Alzheimer’s.
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Nearly three-quarters of Americans with Alzheimer’s (73%) are 75 or older.
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Almost two-thirds of Americans with Alzheimer’s are women.
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Black elders are about twice as likely to develop this disease than older white Americans; Hispanic older adults are about 1.5 times as likely to have Alzheimer’s vs. older white adults.
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And according to the CDC, COVID-19 increases Alzheimer’s risk by an average of 67% among people 65 and older.
Other common dementias
The most common other forms of dementia include:
Vascular dementia, the second most common dementia diagnosis after Alzheimer’s disease. It affects 5% to 10% of people 65 and older, and up to half of those 85 and older. It can occur alone or along with another form of dementia, making diagnosis tricky, according to the Alzheimer’s Association.
People with vascular dementia are not candidates for the new Alzheimer’s drugs, according to Heidebrink, due to higher risk of brain bleeding or aneurysms.
Vascular dementia results from conditions or events that interrupt the flow of blood and oxygen to the brain and damage blood vessels, including:
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Prior strokes, which may be minor and lack symptoms.
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Narrowing of the arteries.
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Abnormalities in the small blood vessels, or the brain’s white matter are often found in people with vascular dementia.
Memory, thinking and behavior can be impacted by the size, location, and number of vascular changes.
Vascular dementia is managed with medication like blood thinners to prevent additional strokes and by reducing risk factors for stroke like hypertension, diabetes, high cholesterol and heart arrhythmias.
Dementia with Lewy bodies occurs when abnormal deposits of a protein called alpha-synuclein develop in the brain’s nerve cells. These deposits, or “Lewy bodies,” impact two vital brain neurotransmitters, which affect memory, learning, cognition, mood, behavior, sleep and movement.
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This progressive disease affects more than 1 million people in the U.S.
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Symptoms usually appear after age 50.
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A 2019 study found this disease the costliest dementia in direct health care costs and utilization. Some symptoms may mimic Parkinson’s or Alzheimer’s disease, making Lewy body dementia difficult to diagnose.
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Early symptoms are treatable, but as yet, there is no treatment or cure for the disease itself.
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Comedian and actor Robin Williams was diagnosed with Lewy body dementia. Prior to his death in 2014, he and his wife Susan went public to foster increased awareness about the disease.
Frontotemporal dementia is actually a group of disorders resulting from ongoing nerve cell loss in the brain’s frontal lobes (behind the forehead) or temporal lobes (behind the ears). It’s the most common cause of dementia in people under 60, on par with Alzheimer’s incidence in people 45-64, according to the UCSF Weill Institute for Neurosciences.
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The functional loss caused by this disease leads to deterioration in behavior, personality and language fluency (but not comprehension), according to the Alzheimer’s Association.
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Many with frontotemporal dementia have difficulty with complex planning or problem solving and a progressive slowing of movement.
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The disease is thought to be hereditary, but there may not always be a family history of this condition.
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In other instances, a single gene can cause the disease in about 10-20% of cases, according to researchers at the UCSF Memory and Aging Center.
Parkinson’s disease dementia happens when there’s a drop-off in thinking and memory at least a year after initial diagnosis of Parkinson’s. As brain changes caused by Parkinson’s disease progress, it can lead to a decline in mental function, attention span and decision-making.
Researchers found that abnormal microscopic deposits composed primarily of alpha-synuclein appear in the brains of people with Parkinson’s disease, similar to those which appear in people diagnosed with dementia with Lewy bodies. However, many people with Parkinson’s disease dementia also have plaques and tangles, which are distinctive features of Alzheimer’s disease.
Mixed dementia occurs when a patient shows symptoms of more than one type of dementia, most commonly a combination of vascular dementia and Alzheimer’s disease. This can make diagnosis and symptom management more difficult. It’s unclear just how many people mixed dementia affects, but according to the Alzheimer’s Association, autopsies show that it’s more prevalent than previously thought.
Dementia is complex, nuanced and multi-faceted. It goes beyond Alzheimer’s disease, encompassing brain changes from a variety of causes, for reasons both known and unknown. But dementia is not an inevitable part of aging. Understanding the varied dimensions of cognitive loss may help reporters also better understand the desperation of families grasping for anything that might help, as well as the limitations and risks of the new drugs.
Resources
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Alzheimer’s Disease and Healthy Aging Data public dataset includes information from the Behavioral Risk Factor Surveillance System (BRFSS) for 2015-2021. Updated May, 2023.
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The National Institute of Neurological Disorders and Stroke (NINDS), Brain Resources and Information Network (BRAIN)
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the Bluefield Project to Cure FTD, from UCSF
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This AHCJ story post on the potential impact Medicare coverage of Alzheimer’s treatment could have on Medicare premiums.
Experts
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Judith Heidebrink, M.D., neurologist and co-lead of the Michigan Alzheimer’s disease center. Contact Noah Fromson fromsonn@med.umich.edu
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David Holtzman, M.D., Scientific director, Hope Center for Neurological Disorders department of neurology, associate director of the Knight Alzheimer’s disease research center. Washington University School of Medicine, St. Louis; contact: Judy Martin Finch, director of communications. martinju@wustl.edu (314) 286-0105
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Karen Marder, M.D.: chief, division of aging and dementia, professor of neurology, Taub Institute on Alzheimer’s disease and the aging brain, Columbia University Medical Center. ksm1@cumc.columbia.edu
