Depression Sufferers More Likely To Develop Alzheimer's Disease
People who suffer from depression have increased risk for developing Alzheimer's disease later in life.
Two similar studies conducted by Dutch and US researchers to uncover the link between depression and Alzheimer's disease. It is clear that there is a link between the conditions, but researches don't give explanations on how the conditions are connected.
One of hypothesis was that depression damages cells of two parts of brain - hippocampus and amygdale - the damage later leads to Alzheimer's disease. However, another research reported that there is no significant difference in brain areas of those with depression and those who never developed the condition.
Another hypothesis is that depression is not a factor causing Alzheimer's disease later in life. It may be just an early sign warning about dementia development. Depression may be associated with changes taking place in brain and reducing neural reserve. Reduced neural reserve decreases brain's ability to tolerate condition associated with Alzheimer's.
Dutch researchers examined 486 people, 33 of whom developed Alzheimer's disease. Those who suffered from depression before ages of 60 where 4 times more at risk for developing Alzheimer's later in life.
US researchers fro Rush University examined 900 people during 13 years, 190 of these people developed Alzheimer's disease within the study period. Those suffering from depression were found to be more likely to develop Alzheimer's disease, just like the patients in Dutch study. However, those with depression history did not show significant depressive symptoms during early Alzheimer's stages.
More research needs to be done to clarify the link between depression and Alzheimer's disease. It's now a question if depression leads to Alzheimer's disease, or there is a reason causing both conditions - one earlier and the other one later in life.