Dale Bredesen is a researcher whose work focuses on cognitive decline and Alzheimer's disease. His published research investigates precision medicine and multi-factorial interventions, including dietary protocols such as the KetoFLEX 12/3 diet and personalized therapeutic programs. Additionally, his studies explore molecular mechanisms, metabolic pathways, and targeted pharmacological agents for Alzheimer's disease.
In trial data from pharmaceutical anti-amyloid therapies, patients homozygous for APOE4 (APOE4/4) deteriorated more than the control group.
"The people who were APOE4/4, and this is 7 million Americans, and in the trial, of course, it represents about 10% of overall Alzheimer's disease, they actually got worse than control. Now, of course, that wasn't mentioned in the publication, but in the evaluation of the publication by an objective third party, it was pointed out, "Well, these people actually got worse, not better."" (said at 0:06:50)
In Phase 3 clinical trial data for monoclonal anti-amyloid therapies such as lecanemab (Clarity AD) and donanemab (TRAILBLAZER-ALZ 2), overall trial populations demonstrated statistically significant slowing of cognitive and functional decline compared to placebo. However, subgroup analyses by APOE ε4 carrier status revealed marked heterogeneity: in the Clarity AD trial data evaluated during regulatory reviews and subsequent analyses, APOE ε4 homozygotes assigned to lecanemab exhibited a point estimate indicating numerically faster decline on the primary Clinical Dementia Rating-Sum of Boxes (CDR-SB) scale compared to the placebo group. While this numerical difference did not achieve statistical significance within that specific small subgroup, it demonstrated an absence of detectable clinical efficacy and a higher rate of amyloid-related imaging abnormalities (ARIA) in APOE ε4 homozygotes compared with heterozygotes and non-carriers.
- context: Lecanemab in Early Alzheimer's Disease. (The New England journal of medicine 2023) · cited 5553x in the literature
"The adjusted least-squares mean change from baseline at 18 months was 1.21 with lecanemab and 1.66 with placebo (difference, -0.45; 95% confidence interval [CI], -0.67 to -0.23; P<0.001)." (abstract, results, passage verified)
pubmedfull study (doi) - context: Donanemab in Early Symptomatic Alzheimer Disease: The TRAILBLAZER-ALZ 2 Randomized Clinica… (JAMA 2023) · cited 2777x in the literature
"LSM change in CDR-SB score at 76 weeks was 1.20 (95% CI, 1.00-1.41) with donanemab and 1.88 (95% CI, 1.68-2.08) with placebo (difference, -0.67 [95% CI, -0.95 to -0.40]; P < .001) in the low/medium tau population and 1.72 (95% CI, 1.53-1.91) with donanemab and 2.42 (95% CI, 2.24-2.60) with placebo (difference, -0.7 [95% CI, -0.95 to -0.45]; P < .001) in the combined population." (abstract, results, passage verified)
pubmedfull study (doi)
Beta-amyloid is a prion, along with PrPSc and alpha-synuclein.
"So what we are proposing is that these prions—and A-beta has turned out to be a prion, as well as PrPSc, as well as alpha-synuclein—these things we already know can sit in your brain for decades protecting the brain." (said at 0:16:32)
The speaker's classification of beta-amyloid (Aβ) and alpha-synuclein alongside PrPSc reflects a prominent scientific paradigm popularized by Stanley Prusiner and colleagues, but requires context. PrPSc is the classical, universally acknowledged infectious prion responsible for transmissible spongiform encephalopathies (such as Creutzfeldt-Jakob disease and scrapie). In contrast, while Aβ and alpha-synuclein exhibit prion-like molecular mechanisms—specifically seeded templating, self-propagation, and cell-to-cell spread—classifying them formally as true 'prions' remains an expanded conceptual definition rather than an established clinical consensus. In broader biomedical literature, Aβ and alpha-synuclein are typically described as 'prion-like' self-propagating proteinopathies because they lack evidence of natural inter-individual transmissibility.
- supports: Expanding spectrum of prion diseases. (Emerging topics in life sciences 2020) · cited 45x in the literature
"Thus, prions are proteins that adopt alternative conformations, which are self-propagating and found in organisms ranging from yeast to humans. Prions have been found in both Alzheimer's (AD) and Parkinson's (PD) diseases. Mutations in APP and α-synuclein genes have been shown to cause familial AD and PD. Recently, AD was found to be a double prion disorder: both Aβ and tau prions feature in this ND. Increasing evidence argues for α-synuclein prions as the cause of PD, multiple system atrophy, and Lewy body dementia." (abstract, passage verified)
pubmedfull study (doi) - context: How an Infection of Sheep Revealed Prion Mechanisms in Alzheimer's Disease and Other Neuro… (International journal of molecular sciences 2021) · cited 54x in the literature
"Although it is not yet universally accepted that all neurodegenerative diseases (NDs) are prion disorders, there is little disagreement that Alzheimer's disease (AD), Parkinson's disease, frontotemporal dementia (FTD), and other NDs are a consequence of protein misfolding, aggregation, and spread." (abstract, passage verified)
pubmedfull study (doi)
Parkinson's disease occurs in approximately 1.8 men for every woman, while Alzheimer's disease affects roughly twice as many women as men.
"it's about 1.8 men for each woman. We've got women getting more Alzheimer's, almost 2 to one. We've got men getting more ALS and men getting more Parkinson's." (said at 0:57:58)
Epidemiological studies confirm sex disparities in both neurodegenerative diseases, but the exact ratios are slightly more nuanced. Meta-analyses show that Parkinson's disease is significantly more common in men than women, with an overall male-to-female ratio of approximately 1.5 (increasing with age to over 1.6 to 2.0 in older cohorts). For Alzheimer's disease, approximately two-thirds of diagnosed individuals are women (roughly a 2:1 absolute number/crude prevalence in the population), though much of this disparity is driven by women living longer on average, while age-adjusted lifetime risk estimates show a more modest excess risk for women.