From The New Yorker · Manvir Singh · · 2m
Alzheimer's Disease Diagnosis Shifts Global Health Landscape
New blood tests and drugs target Alzheimer's disease before symptoms appear.
In brief
New blood tests and drugs target Alzheimer's disease before symptoms appear. Alzheimer's disease is now defined by biomarkers like amyloid plaques, affecting hundreds of millions globally with potential early treatments. Originally reported by The New Yorker.
Alzheimer's Conference Optimism
Ten thousand people attended London's Alzheimer's Association conference this July, with virtual participants joining.
“We estimate a man by how much he remembers”
Decades of Research Disappointment
The U.S. spent twenty billion dollars on Alzheimer's research from 1974 to 2.020 without approving a single treatment.
Current Alzheimer's Impact
Alzheimer's affects one in nine Americans over sixty-five and costs the economy three-quarters of a trillion dollars annually.
Alzheimer's Disease Definition Shift
Alzheimer's disease is now defined by biomarkers like amyloid plaques, not just cognitive decline.
Amyloid as Key Biomarker
Blood tests developed over five years now measure amyloid levels as accurately as PET scans.
FDA Approves New Drugs
The FDA approved three antibody treatments since 2021 to slow Alzheimer's progression.
Kewman's Genetic Risk
Kewman, a seventy-six-year-old retired psychologist, carries two copies of the APOE 4 gene, increasing Alzheimer's risk.
Preclinical Diagnosis
Cognitively normal people with amyloid plaques are now classified as having preclinical Alzheimer's disease.
Amyloid-Targeting Drugs
Lecanemab and donanemab are FDA-approved drugs that target amyloid plaques to slow cognitive decline.
Kewman's Treatment Trial
Kewman participated in a trial testing lecanemab, receiving monthly infusions for four years with no cognitive decline.
Treatment Effectiveness Debate
Cochrane review found amyloid-targeting drugs show little to no difference in cognitive decline, despite reducing amyloid plaques.
Alzheimer's Association Stance
The Alzheimer's Association argues biomarkers should define Alzheimer's disease to enable early treatment.
Clinical Trial Challenges
Early trials of amyloid-targeting drugs showed mixed results, with some patients experiencing brain swelling or microbleeds.
Amyloid's Role in Disease
Amyloid plaques and tau tangles are now considered key biomarkers for Alzheimer's disease, even before symptoms appear.
Kewman's Experience
Kewman, with high genetic risk, remains cognitively normal despite having amyloid plaques.
Future Treatment Outlook
Early treatment of amyloid buildup may prevent Alzheimer's dementia, but current drugs show modest benefits.
In short
Alzheimer's disease is now defined by biomarkers like amyloid plaques, affecting hundreds of millions globally with potential early treatments.
