Alzheimer's Dementia: China-Sweden joint study: Higher education can cushion the impact of middle-aged depression on dementia

In addition to dementia, depression is another high-incidence neuropsychiatric disease, affecting more than 264 million people worldwide.
Depression is related to cognitive dysfunction.
Overall, depression doubles the risk of developing dementia.

However, cognitive dysfunction is a common manifestation of depression in later life, and depression often coexists with dementia.
Therefore, whether depression is a risk factor for dementia or a prodromal stage of dementia is still under debate.
In order to uncover the essential link between depression and dementia, it is very important to study the time window of depression in the course of life.
So far, longitudinal studies have proved the relationship between middle-aged depression and dementia.

However, to date, few studies have been able to apply the life-course method to distinguish the relationship between depression and dementia in different life periods.
The impact of depression in the life course on dementia is still controversial.
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More and more evidence shows that both genetic factors and early environmental factors are related to the occurrence of depression and dementia.
One advantage of twin studies is that it can better deal with residual confounding.
These confoundings are caused by unmeasured genetic predispositions shared by twins and their early environment, which may help us understand whether (to what extent) these factors (Above) can lead to an association between depression and dementia.
Other environmental factors, such as cognitive reserve indicators, namely higher education, are also associated with a lower risk of dementia.
However, whether higher education can change the risk of dementia associated with depression is still unknown.

In this way, Wenzhe Yang and others of Tianjin Medical University explored:

(1) Investigate the association between depression and dementia risk from the perspective of life course
(2) Assess whether genetic and early family factors can explain this association
(3) Explore the moderating role of education in the depression-dementia association.

They followed up for 18 years of dementia-free twins (n=41 727) in the Swedish twin registration system.

They found that in the GEE model, the multiple-adjusted odds ratio (ORs of 1.

Original Source: onlinelibrary.