Cognitive Decline

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• Witnessing the cognitive decline in some of our loved ones is something many of us have experienced. Social withdrawal, mood changes, memory loss and bizarre behavior are the early signs of a process that may happen in a very steady way or in a very fast decline.

• Although we can not be sure what causes it, when it is triggered and what fuels it, the decline begins many years before symptoms appear. An adult in his/her thirties could, unknowingly, have many factors or propensities for developing Alzheimer’s disease. We think about dementia only after the age of 50, but it is important to spread the message that the sooner we engage in purposeful activities or life habits (i.e. in the 30s or 40s) the greater the possibility of preventing or reducing the cognitive decline (1). 

• Dementia presents itself with characteristic symptoms, i.e. difficulties with memory, language, problem solving and other thinking skills that affect a person's ability to perform everyday activities. Many are the causes involved, with Parkinson’s disease being one of them and Alzheimer’s disease being the most common (2).  The full-blown dementia picture is most of the time preceded by mild cognitive impairment (MCI), and not everybody with MCI will develop a more severe form of Alzheimer’s disease. Since people with MCI have subtle cognitive changes that do not interfere with everyday activities and are still able to function independently, any potential treatment, pharmacological or not, preventing full progression would significantly improve the quality of life. 

• The potential benefits that exercise, both aerobic and anaerobic, has on cognitive function and on its decline has been clearly shown (3,4).
  While specific risk factors for dementia like age, genetics and family history can not be changed, many modifiable risks could be. Two of these factors are of major importance: staying physically activity and staying socially and mentally engaged. Focusing on these two factors  may indeed prevent or delay up to 40% of dementia cases (3-19). 

References

1. Gupta S. Keep Sharp. Simon & Schuster Editor. 2021.

2. 2021 Alzheimer’s disease Facts and Figures. https://www.alz.org/media/Documents/alzheimers-facts-and-figures.pdf.

3. Groot C, Hooghiemstra AM, Raijmakers PG, van Berckel BN, Scheltens P, Scherder E, et al. The effect of physical activity on cognitive function in patients with dementia: A meta-analysis of randomized control trials. Ageing Res Rev 2016;25:13-23.

4. Farina N, Rusted J, Tabet N. The effect of exercise interventions on cognitive outcome in Alzheimer’s disease: A systematic review. Int Psychogeriatr 2014;26(1):9-18.

5. Livingston G, Huntley J, Sommerlad A, Ames D, Ballard C, Banerjee S, et al. Dementia prevention, intervention, and care: 2020 report of the Lancet Commission. Lancet 2020;396(10248):413-46.

6. Najar J, Ostling S, Gudmundsson P, Sundh V, Johansson L, Kern S, et al. Cognitive and physical activity and dementia: A 44-year longitudinal population study of women. Neurology 2019;92(12):e1322-e1330.

7. Staf RT, Hogan MJ, Williams DS, Whalley LJ. Intellectual engagement and cognitive ability in later life (the “use it or lose it” conjecture): Longitudinal, prospective study. BMJ 2018;363:k4925.

8. Wang H-X, Xu W, Pei J-J. Leisure activities, cognition and dementia. BBA-Mol Basis Dis 2012;1822(3):482-91.

9. Wang H-X, Karp A, Winblad B, Fratiglioni L. Late-life engagement in social and leisure activities is associated with a decreased risk of dementia: A longitudinal study from the Kungsholmen Project. Am J Epidemiol 2002;155(12):1081-7.

10. Saczynski JS, Pfeifer LA, Masaki K, Korf ES, Laurin D, White L, et al. The effect of social engagement on incident dementia: The Honolulu-Asia Aging Study. Am J Epidemiol 2006;163(5):433-40.

11. Karp A, Paillard-Borg S, Wang H-X, Silverstein M, Winblad B, Fratiglioni L. Mental, physical and social components in leisure activities equally contribute to decrease dementia risk. Dement Geriatr Cogn Disord 2005;21(2):65-73.

12. Di Marco LY, Marzo A, Muñoz-Ruiz M, Ikram MA, Kivipelto M, Ruefenacht D, et al. Modifiable lifestyle factors in dementia: A systematic review of longitudinal observational cohort studies. J Alzheimers Dis 2014;42(1)119-35.

13. James BD, Wilson RS, Barnes LL, Bennett DA. Late-life social activity and cognitive decline in old age. J Int Neuropsychol Soc 2011;17(6):998-1005.

14. Yates LA, Ziser S, Spector A, Orrell M. Cognitive leisure activities and future risk of cognitive impairment and dementia: Systematic review and meta-analysis. Int Psychogeriatr 2016;9:1-16.

15. Ball K, Berch DB, Helmers KF, Jobe JB, Leveck MD, Marsiske M, et al. Effects of cognitive training interventions with older adults: A randomized controlled trial. JAMA 2002;288(18):2271-81.

16. Hall CB, Lipton RB, Sliwinski M, Katz MJ, Derby CA, Verghese J. Cognitive activities delay onset of memory decline in persons who develop dementia. Neurology 2009;73:356-61.

17. Sanjeev G, Weuve J, Jackson JW, VanderWeele TJ, Bennett DA, Grodstein F, et al. Late-life cognitive activity and dementia. Epidemiology 2016;27(5):732-42.

18. Wilson RS, Bennett DA, Bienias JL, Aggarwal NT, Mendes De Leon CF, Morris MC, et al. Cognitive activity and incident AD in a population-based sample of older persons. Neurology 2002;59(12):1910-4.

19. Wang Z, Marseglia A, Shang Y, Dintica C, Patrone C, Xu W. Leisure activity and social integration mitigate the risk of dementia related to cardiometabolic diseases: A population-based longitudinal study. Alzheimer’s Dement. 2020;16:316-25.

• Parkinson’s condition is a neurodegenerative disease with motor symptoms (tremor, limb rigidity, gait and balance problems and slow movements) and non-motor symptoms (depression, sleep disorders,behavior disorders, loss of sense of smell and cognitive impairment) (1).

• In the United States, there are approximately 1 million people with PD, with 60,000 newly diagnosed every year. The incidence of PD increases with age, but about 4% are diagnosed before the age of 50.

• The most updated data about the incidence of PD in Colorado goes back to 2018, with 11,500 people affected by this condition (2). 

• Exercise and physical activity are considered to be a vital component to maintain balance and mobility and conduct activities of daily living. The Parkinson's Outcomes Project demonstrated that people with PD who start exercising earlier at a minimum of 2.5 hours a week, experienced a slower decline in quality of life compared to those who started later. Establishing early exercise habits is essential to overall disease management, with activities that focus on aerobic capacity, strength, balance, agility, multitasking and flexibility (1).

References

1. Parkinson’s Foundation. www.parkinson.org/Living-with-Parkinsons/Managing-Parkinsons.

2. Marras, C., Beck, J. C., Bower, J. H., Roberts, E., Ritz, B., Ross, G. W., Abbott, R. D., Savica, R., Van Den Eeden, S. K., Willis, A. W., Tanner, CM, on behalf of the Parkinson’s Foundation P4 Group (2018). Prevalence of Parkinson’s disease across North America. Npj Parkinson's Disease, 4(1), 1–7.

• Alzheimer’s condition is the most common type of dementia. It starts with very mild memory loss and may progress to total withdrawal from the surrounding environment (1).

• In the United States, 1 in 9 people age 65 and older has Alzheimer’s dementia. This becomes 1 in 8  after age 75 and 1 in 3 after age 85 (2).

• In Colorado, the number of people age 65 and older with Alzheimer’s dementia in 2020 was 76,000, projected to become 92,000 in 2025 (3).

References

1. https://www.cdc.gov/aging/aginginfo/alzheimers.htm

2. Rajan KB, Weuve J, Barnes LL, McAninch EA, Wilson RS, Evans DA. Population estimate of people with clinical AD and mild cognitive impairment in the United States (2020-2060). Alzheimers Dement 2021;17. In press.

3. Weuve J, Hebert LE, Scherr PA, Evans DA. Prevalence of Alzheimer disease in U.S. states. Epidemiology 2015;26(1):E4-E6.