When Should I Seek Treatment for Cognitive Decline?

by Ericka Naegle MS, RDNLifestyle
Face of a clock showing twelve o'clock

Cognitive decline, like many chronic diseases, is best prevented, rather than treated. Many of the risk factors for cognitive decline are related to diet and lifestyle, so it is never too early to make changes that may prevent us from ever developing dementia. Studies show that modifiable risk factors, including diet and lifestyle, account for 40-50% of all dementia (1,2). If we do start to develop symptoms of cognitive impairment, it is never too early to seek treatment, as these same risk factors contribute to disease progression.

Cognitive decline is a process that can start in the brain before we show any cognitive symptoms (3). The first symptoms manifest as mild cognitive impairment (MCI). This is diagnosed when a person experiences greater memory loss than is expected for their age but does not meet the clinical criteria for dementia. MCI is considered to be a transitional stage before a dementia diagnosis, and people diagnosed with MCI progress to dementia or Alzheimer’s disease at a rate of 10-15% per year (4). However, MCI does not always progress and can even be reversed (5), especially when we act on the range of modifiable risk factors for the disease.

There are certain risk factors for cognitive decline that we cannot change. Research has shown that age, genetics, education level and sex all influence the risk for dementia. Those who are at greater risk include carriers of at least one ApoE e4 allele, those who received less than a high school education and women. Men aren’t out of the woods, however. While women tend to show faster disease progression and are at higher risk of severe dementia, men are at higher risk of death due to cognitive decline (6). When it comes to age, our risk doesn’t simply increase with age. The age of MCI onset can actually impact how quickly cognitive decline progresses. Those who experience earlier onset of MCI (before age 81) can progress to severe Alzheimer’s disease more quickly than those whose MCI begins between ages 81 and 86 (6).

The good news is that the majority of risk factors for cognitive decline are modifiable, which is to say that we can make changes that reduce the risk. According to British researchers, lifestyle changes can slow or prevent future disease (3) – but we need to intervene.

Several modifiable risk factors for cognitive decline have to do with our metabolic health: high blood pressure, obesity and diabetes. What may be surprising is that these risk factors may have their biggest impact on our dementia risk not when we are older, but when we are in midlife. Studies have shown that high blood pressure in midlife (40-64 years) increases the risk of future dementia by 60% (1,2,7). And while the research disagrees about blood pressure later in life, one large study found that dementia risk grew even more in participants whose blood pressure remained high around age 69. Similarly, obesity in midlife can increase dementia risk by 60% (1,2). Researchers analyzed 19 studies that followed participants aged 35 to 65 and found a correlation between higher BMI and dementia (8). Finally, midlife diabetes has been found to increase dementia risk dramatically. In one study in twins, siblings with midlife diabetes were found to be 2.4 times more likely to develop dementia as twin siblings who did not have diabetes (9).

Recognizing and acting on these risk factors early is the best way to reduce the risk of developing MCI, as well as to slow disease progression if MCI does develop. Research shows that people in good physical health can withstand more harmful changes in the brain without experiencing cognitive impairment (10).

Diet and lifestyle-related treatments are some of the best ways to take action to minimize your risk. Many studies show that the right diet can reduce dementia risk and slow cognitive decline (1,11). One French study even found that dietary factors can reduce dementia and Alzheimer’s risk by 30-40% (12). An analysis of 20 studies on weight loss and cognitive function found that weight loss of at least 2 kg (4.4 pounds) led to significant improvements in attention, memory, executive function and language in participants under age 65 (13). Improving sleep quality and regular physical exercise can also reduce dementia risk (1,11).

The research shows that a complex web of factors can influence our likelihood for developing cognitive impairment and dementia.We should seek treatments that impact as many of these variables as possible, and which are individualized to meet our specific needs. And we should seek treatment early.

Preventive measures are the best protection (11). If symptoms of cognitive decline do begin to appear, the earlier we start treatment, the greater likelihood we can slow, or even reverse, decline, because our bodies are healthier and more able to respond (11). In a study on 100 patients in whom the Bredesen Protocol reversed cognitive decline, those who showed less decline at the start of the intervention responded to treatment better than those whose disease had progressed further(14). On the other hand, even patients with severe dementia showed improvement. As the 2020 Lancet commission wrote, “contributions to the risk and mitigation of dementia begin early and continue throughout life, so it is never too early or too late to start” (1).

References

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  2. Barnes, D. E., & Yaffe, K. (2011). The projected impact of risk factor reduction on Alzheimer’s Disease orevalence.Lancet Neurology,10(9), 819–828. doi.org/10.1016/S1474-4422(11)70072-2
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  5. Forrester, S. N., Gallo, J. J., Smith, G. S., & Leoutsakos, J. M. S. (2016). Patterns of neuropsychiatric symptoms in mild cognitive impairment and risk of dementia.American Journal of Geriatric Psychiatry,24(2), 117–125. doi.org/10.1016/j.jagp.2015.05.007
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  8. Albanese, E., Launer, L. J., Egger, M., Prince, M. J., Giannakopoulos, P., Wolters, F. J., & Egan, K. (2017). Body mass index in midlife and dementia: Systematic review and meta‐regression analysis of 589,649 men and women followed in longitudinal studies.Alzheimer’s & Dementia: Diagnosis, Assessment & Disease Monitoring,8(1), 165–178. doi.org/10.1016/j.dadm.2017.05.007
  9. Xu, W., Qiu, C., Gatz, M., Pedersen, N. L., Johansson, B., & Fratiglioni, L. (2009). Mid- and late-life diabetes in relation to the risk of dementia: A population-based twin study.Diabetes,58(1), 71–77. doi.org/10.2337/db08-0586
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