Alzheimer’s disease is a neurodegenerative disorder that mainly affects older adults causing dementia.
Dementia is the loss of cognitive functioning and behavioral abilities such that it interferes with a person’s daily life and activities.
Pathogenesis
The exact cause of Alzheimer’s disease is still not known but there are some proposed mechanisms for the loss of brain functioning.
Extracellular deposits of amyloid beta peptides forming Neuritic plaques in the grey matter of brain have a neurotoxic effect.
Neurofibrillary degeneration demonstrated by intracellular neurofibrillary tangles composed of hyperphosphorylated tau protein.
Other Age-related changes may include atrophy (shrinking) of certain parts of the brain, inflammation, blood vessel damage, production of unstable molecules called free radicals, and mitochondrial dysfunction. [3]
Risk Factors
Non-Modifiable
Age - is the strongest risk factor for AD, in people >65 years , the risk doubles every five years.
Sex - (females > males)
Family history – especially in early onset Alzheimer’s
Genetics - Apolipoprotein E ε4 allele, APP gene , presenilin 1 and 2
Modifiable
Diabetes and insulin resistance
Obesity
Metabolic syndrome
Hypertension
Hypercholesterolemia
Cerebrovascular disease
Traumatic brain injury
Depression
Psychological and physiological stress
Diet rich in saturated fats
Excessive alcohol consumption
Smoking
Cognitive inactivity
Physical inactivity
Sleep disordered breathing
Clinical features
Symptoms are thought to appear a decade or more after changes in the brain begin. These changes initially appear to take place in the hippocampus and the entorhinal cortex, which are memory centers of the brain.
The symptoms include
Memory impairment – typically one of the first signs
Language impairment
Temporal /spatial disorientation
Impaired reasoning or judgment
Personality and Behavioral changes
Some less common symptoms such as apraxia, alexia, agnosia may also be present
As the disease progresses, they become unable to carry out daily tasks such as getting dressed to the point where they become completely dependent on others for care.
Prevention
There have been multiple researches including ongoing ones to find a treatment for AD but none have been able to find a cure. There are however some medications used to decrease the progression and maybe give symptomatic relief. This means that the best way to fight AD is to try and prevent it. It is found that up to 30% of AD maybe preventable through modification of risk factors [4]. This is not to mean that the following strategies will completely eliminate the potential of getting AD but they will decrease the risk.
The major strategy for prevention is to actively maintain brain health by
Doing cognitive leisure activities - crossword puzzles, card games, computer use, arts and crafts e.t.c
Life-long learning – the brain needs exercise as much as the body.
Social engagement
Engaging in mindfulness and wellness activities
Listening to music
Another thing to focus on is Physical activity which may lead to a 20–65% risk reduction depending on the type and intensity and exercise. [4]
The third thing is Diet modification by
Increasing Omega-3 intake
Avoiding increased intake of saturated fat
Increasing Vitamin c intake
References
1. Uptodate
2. Galvin, J.E. (2017). Prevention of Alzheimer’s Disease: Lessons Learned and Applied. Journal of the American Geriatrics Society, [online] 65(10), pp.2128–2133. Doi:https://doi.org/10.1111/jgs.14997.
3. National Institute on Aging (2023). Alzheimer’s Disease Fact Sheet. [online] National Institute on Aging. Available at: https://www.nia.nih.gov/health/alzheimers-disease-fact-sheet [Accessed 23 Sep. 2023].
4. Yu, J.-T., Xu, W., Tan, C.-C., Andrieu, S., Suckling, J., Evangelou, E., Pan, A., Zhang, C., Jia, J., Feng, L., Kua, E.-H., Wang, Y.-J., Wang, H.-F., Tan, M.-S., Li, J.-Q., Hou, X.-H., Wan, Y., Tan, L., Mok, V. and Tan, L. (2020). Evidence-based prevention of Alzheimer’s disease: systematic review and meta-analysis of 243 observational prospective studies and 153 randomised controlled trials. Journal of Neurology, Neurosurgery & Psychiatry, [online] 91(11), pp.1201–1209. Doi:https://doi.org/10.1136/jnnp-2019-321913.
5. Lista, S., Dubois, B. and Hampel, H. (2014). Paths to Alzheimer’s Disease prevention: from Modifiable Risk Factors to Biomarker Enrichment Strategies. The Journal of nutrition, Health & Aging, 19(2), pp.154–163. Doi:https://doi.org/10.1007/s12603-014-0515-3.
Assessed and Endorsed by the MedReport Medical Review Board
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