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