Dr. Mark Gordon on alzheimers: what the evidence says · JRE #2262
SUBJECT: ALZHEIMERS
The short answer
Dr. Gordon claims recent studies show 95 percent of Alzheimer's cases are due to trauma and aging and only 5 percent are genetic. The claim conflates two different things. It is accurate that only a small share of Alzheimer's cases (roughly 1 to 5 percent) are caused by rare inherited autosomal dominant mutations in the APP, PSEN1, or PSEN2 genes, which mostly drive early-onset disease.
Not a true/false call. Every claim is logged with its sources; read the exhibits below.
Well, if you look at the real studies recently, 95% of the cases of Alzheimer's disease appear to be due to trauma and aging. Genetics, only 5%.
What the evidence says 01 / RECORD
The claim conflates two different things. It is accurate that only a small share of Alzheimer's cases (roughly 1 to 5 percent) are caused by rare inherited autosomal dominant mutations in the APP, PSEN1, or PSEN2 genes, which mostly drive early-onset disease. It does not follow that the remaining 95 percent are non-genetic or attributable to trauma. The National Institute on Aging states that in most cases Alzheimer's does not have a single genetic cause and is instead influenced by multiple genes (notably the APOE risk gene) in combination with lifestyle and environmental factors. Peer-reviewed reviews estimate the heritability of common late-onset Alzheimer's at roughly 60 to 80 percent, so the disease is strongly genetic even though it is not caused by one deterministic mutation. Head trauma is a recognized risk factor for dementia but is not established as the cause of 95 percent of Alzheimer's cases, and no cited epidemiology supports a trauma-and-aging attribution at that level.