Alzheimer Dementia: The overall reduction in the incidence of dementia, which factors are "contributory"

Dementia ranks among the top causes of adult disability, and its global impact is expected to rise
.
Contrary to expectations, some countries have reported a decline in incidence

In Europe and the United States, the incidence rate has fallen by 13% every ten years in the past 25 years

The 2020 Lancet Dementia Prevention , Intervention and Care Committee recently published a life course model on how to prevent dementia with 12 risk factors, indicating low education, hearing impairment, brain injury, high blood pressure, excessive drinking, Obesity, smoking, depression, social isolation, lack of exercise, diabetes, and air pollution together account for 40% of dementia
.

However, only a few studies have examined whether these factors can explain the long-term decline in new dementia cases.
Their findings are inconsistent, and it is doubtful whether these factors are the main drivers of the long-term decline
.

In fact, the results of a multi-generational study indicate that changes in the characteristics of consecutive birth groups unrelated to traditional risk factors may be the main driving force for the long-term decline in dementia

This is consistent with two recent studies, which observed a decrease in the incidence of dementia in all birth cohorts, although neither study provided evidence to rule out the possibility of traditional risk factors
.

In other words, research is still needed to explore the possible causes of the long-term decline in dementia, and it is best to overcome the limitations of previous studies in sample selection, self-reporting and lack of information, and long evaluation intervals
.

In this way, Emilie R.

They conducted a cohort study (N=1,757,168) of all people ≥65 years of age in Denmark from 2005 to 2018
.
The annual incidence of dementia and the four-factor population attributable risk were calculated, and the birth cohort trend was studied

From 2005 to 2018, the incidence of dementia in men dropped by 22.
5%, and the incidence of dementia in women dropped by 34.
2%
.
The demographic attribution risk of low education, low wealth, and stroke has also decreased

Regardless of these improvements, the incidence of dementia has declined in the continuous birth cohort
.

The important significance of this study is that it has found that most of the observed plasticity in advanced dementia is related to the risk reduction in the continuous birth cohort, which has nothing to do with the improvement of traditional risk factors