What factors besides age and genetics influence the prevalence of Alzheimer's?

Question

What factors have been identified to account for the projected increase in Alzheimer's reported by the Alzheimer's Association?

In particular they note:

An estimated 5.7 million Americans of all ages are living with Alzheimer's dementia in 2018. This number includes an estimated 5.5 million people age 65 and older and approximately 200,000 individuals under age 65 who have younger-onset Alzheimer's.

I am most interested in factors outside of age or genetics which I can't do much about.

Also, I don't know how to research a question such as this outside of an internet search. Hopefully the references in any answers will give me a hint on how I can research questions such as this better myself.

Answer 1

How about this list from the Alzheimer Society of Canada? It differentiates between modifiable and non-modifiable risk factors and goes on to explain how and why which risk factors are risk factors.

Modifiable risk-factors:
- Risk factors for both Alzheimer’s disease and cardiovascular diseases
- Smoking
- High Blood Pressure
- Diabetes
- High Cholesterol
- Obesity & Low Physical Activity

Other risk factors
- Alcohol
- Low levels of education
- Depression
- Head Injuries

Non-modifiable risk factors: - Age
- Family History and Genetics
- Gender

^{Source: Alzheimer Society of Canada. Risk factors. Accessed 01/01/2019}

Answer 2

This Medscape article July 29, 2023 projected an actual count of AD cases in Chicago to the entire US population by race and suggested that

In addition to older age, what’s likely driving elevated AD prevalence in these areas is the substantially larger proportion of minority populations who are at higher risk for AD, possibly due to health disparities.

I note that the projection of a count in Chicago to the entire US population is questionable in and of itself. as is using that to suggest health disparities (meaning groups other than white having less access to health care presumably) may be causal.

The Alzheimer's Association compiled report about what is currently known about reducing risk of Alzheimer's discusses

1. Cardiovascular Health
2. Exercise
3. Diabetes and Obesity
4. Traumatic Brain Injury
5. Tobacco and Alcohol
6. Diet and Nutrition
7. Sleep
8. Sensory Impairment
9. Social Engagement

A CDC article on Alzheimer's does include an image showing racial/ethnic percentage prevalence estimate:

There are, of course, racial differences in the prevalence of the risk factors listed above, which, I suppose, might be attributed in some part to lack of adequate health care. Controlling blood pressure, for example, is very important and medication is usually required.