Discuss the evidence for risk and protective factors in Alzheimer's disease

Cognitive reserve

see specific diagram for this topic

Risk/protective factors

allele /genetics

Monolinguals

earlier onset (65 vs 69) and thus bilingualism seems to add to cognitive reserve

it's not restricted to Alzheimers but rather prime example and not clear how far it extends to other kinds of dementia

No difference between 2 or more languages

Brain training

whatever protects against amyloid (increases cognitive reserve)

brain is relatively plastic, although abilities can be altered

companies claim to be able to improve cognitive abilities

no study to date has demonstrated that brain training cures or prevents Alzheimer's

e.g. lumosity

also claim to lessen risk of Alzheimers!

but unable to support due to poor studies

Anguera et al. 2013: neuroracer game found to strengthen focus ability in elderly. also appeared to transfer to improvement in working memory. increased prefrontal cortex activity.

no requirements e.g. like for clinical drug trials for example

however, didn't explain criteria that was not met. low power and small sample. only 3/11 sig outcomes. no control. no correction for multiple test. bare sig. needed more replication for false positives.

while it's a pretty good study, it's more like a pilot study

Post-TMS

memory activation bilaterally shows memory performance improved

Bentwich et al. 2011: TMS combined with cognitive training (intensive therapeutic regime)

Rabey et al. 2013: improvement for experimental, decrease for control/shame. significant

Alzheimer disease assessment scale

well controlled, double blind, placebo study

especially during mild stages

Lee et al 2016: "remarkable" in memory and language domains, which are seriously impacted by Alzheimers

drug only temporarily and partially effective

no side effects, safe

risk factors: amyloid deposition

however, it is a very slow process and there are more than 30% of cognitively normal subjects with amyloid deposition

amyloid deposition does not correlate strongly with cognition - neuronal injury biomarkers correlate strongly with cognition

Vemuri et al 2012: wanted to figure out how alzheimer was improved by cognitive reserve and studied how lifestyle led to this. found that lifetime (early start) of intellectual activity led to larger score while current intellectual activity less so but still there. physical activity did not have significant impact. education/occupation was important

Lee et al 2016: combination with cholinesterase inhibitors = effective especially during mild stages

different studies by same authors; Bentwich et al (2011) and Rabey et al. (2013, 2016): it's safe, new and effective to improve cognitive function in Alzheimer's