Risk Factors and Interference of Alzheimer’s Disease in Adults

By Joon Lim

The average life expectancy around the world is continuously rising (Aburto et al., 2020), and neurodegenerative diseases are increasing as a threat to the health of the elderly. According to Alzheimer’s News Today (Naqvi, 2020), there are approximately 44 million people suffering from Alzheimer’s or dementia related disorders worldwide. Alzheimer’s Disease (AD) has been thoroughly studied in the past and will continue to be studied. So far, there has been a converging agreement to AD being caused by amyloid-beta (Aβ) peptide levels increasing, accumulating to form neurofibrillary tangles (Crous-Bou et al., 2017).

Several companies have risen to develop drugs to treat AD. These include AVP-786 by Avanir Pharmaceuticals, AXS-05 by Axsome Therapeutics, and AMG520 by Amgen who collaborated with Novartis (Speights, 2020). Additionally, Biogen Inc. developed a drug called aducanumab (BIIB037) for which it demanded approval, even though it was seen to not have significant effects last year. Reanalysis of the data, however, suggested 18 months later that subjects who had taken the drug had a 15% to 27% less decline in cognitive abilities in comparison to the placebo group subjects (Flajolet, 2020). BIIB037 works as an antibody that binds to aggregated Aβ through epitope targeting (Flavell, 2020). Despite the efforts in drug development for AD, however, there is still a low chance of producing a successful drug that will bring effects that are statistically significant, let alone cure AD. More research on AD is needed and the best option, for now, is to take precautions and change our lifestyles.

There have been observational studies on lifestyles and behaviour in life that leads to AD or other cognitive disorders. For instance, physical inactivity, mental inactivity, smoking, diabetes, depression, poor diet (Daviglus et al., 2010), hypertension, obesity, and lack of education in juvenile years of life (Barnes & Yaffe, 2011). Such lifestyles are changeable, and this change could become the primary solution for AD prevention. 

From the above, diabetes mellitus has been found to be one of the high-risk factors of AD, due to the intervening action of insulin-degrading enzyme (hyper-insulinemia induced competitive inhibition) (Farris et al, 2003). On the other hand, the relationship between smoking and AD risk is still not so clear. However, almost 14% of AD cases can be linked to smoking, due to its high prevalence (Barnes & Yaffe, 2011). Moreover, in the study Vos et al., 2017, subjects with higher physical activity levels have shown a reduced risk of AD (Vos et al. 2017). 

Individuals, especially ones from the younger generations, should be given guidance on how to prevent AD and other neurodegenerative disorders. There are factors that cannot be changed such as genetics, life stressors and education, depending on the situation within family. However, there are many other factors that can be controlled to reduce the risk of AD and it is important that these factors are handled correctly. This includes exercising if the individual is not already doing so and challenging oneself more cognitively. For example, one can try coming across new genres of books to read or, if one plays a ball sport, bodybuilding can help with different neuromuscular development (Fargo, 2020).

Early intervention for the prevention of dementia in young adults is important, however, intervention in the elderly is equally important. The Finnish Geriatric Intervention Study to Prevent Cognitive Impairment and Disability study (Kivipelto et al., 2013) investigated whether a multidomain intervention could inhibit decreased cognition in the elderly (Crous-Bou et al., 2017). 1200 participants showed increased risk in decreased cognition and it has been shown that intervention in factors such as exercise, cognitive practises and diet can result in improved cognitive abilities in older people whom are at risk of neurodegenerative disorders. 

References:

Aburto, J.M. et al. (2020) Dynamics of life expectancy and life span equality. PNAS.

Naqvi, E., (2020). Alzheimer’S Disease Statistics. [online] Alzheimer’s News Today. Available at: <https://alzheimersnewstoday.com/alzheimers-disease-statistics/&gt; [Accessed 25 August 2020].

Crous-Bou M. et al. (2017) Alzheimer’s disease prevention: from risk factors to early intervention. Alzheimer’s Research & Therapy.

Speights, K., 2020. 3 Leading Alzheimer’s Disease Drugs In Development After Biogen’s Aducanumab Flop | The Motley Fool. [online] The Motley Fool. Available at: <https://www.fool.com/investing/2019/03/30/3-leading-alzheimers-disease-drugs-in-development.aspx&gt; [Accessed 26 August 2020].

Flajolet, M., 2020. Drug Company To Pursue Approval Of Aducanumab, New Drug For Alzheimer’S. [online] Fisher Center for Alzheimer’s Research Foundation. Available at: <https://www.alzinfo.org/articles/treatment/drug-company-to-pursue-approval-of-aducanumab-new-drug-for-alzheimers/&gt; [Accessed 26 August 2020].

Laura Flavell, P., 2020. Aducanumab. [online] Alzheimer’s News Today. Available at: <https://alzheimersnewstoday.com/aducanumab/&gt; [Accessed 26 August 2020].

Martha L.D. et al. (2010) National Institutes of Health State-of-the-Science Conference statement: preventing Alzheimer disease and cognitive decline. Ann Intern Med.

Barnes D.E., Yaffe K. (2011) The projected effect of risk factor reduction on Alzheimers’ disease prevalence. Lancet Neurol.

Farris W. et al. (2003) Insulin-degrading enzyme regulates the levels of insulin, amyloid beta-protein, and the beta-amyloid precursor protein intracellular domain in vivo. Proc Natl Acad Sci U S A.

Vos S.J.B. et al. (2017) Modifiable risk factors for prevention of dementia in midlife, late life and the oldest-old: validation of the LIBRA Index. J Alzheimers Dis.

Fargo K. (2020) Identifying Alzheimer’s risk factors in young people. [online] Thought Leaders. Available at: https://www.news-medical.net/news/20200818/Identifying-Alzheimere28099s-risk-factors-in-young-people.aspx [Accessed 26 August 2020].Kivipelto M, et al. (2015) The Finnish Geriatric Intervention Study to Prevent Cognitive Impairment and Disability (FINGER): study design and progress. Alzheimers Dement.