Alzheimer's and Depression

According to a study by researchers at the Alzheimer's Disease Research Center at Mount Sinai School of Medicine, those with a lifetime history of depression are associated with the increased plaques and tangles in the brains of those with Alzheimer's and those who have a more rapid cognitive decline. This study has now been published in the February issue of Archives of General Psychiatry.
According to the background information in the article, previous studies have linked depression and Alzheimer's. Those with a lifetime history of major depressive disorder may be more likely diagnosed with Alzheimer's. Also, both diseases are likely to affect the brain's memory related temporal lobes. Depression is likely to cause atrophy of the hippocampus, which is the area where the largest amounts of plaques and tangles form in those with Alzheimer's disease.
To assess how depression might affect the development of Alzheimer's, researchers compared the brains of 44 patients who had Alzheimer's with a history of depression to 51 without. This group included 32 men and 63 women who had an average age of death of 81 years.
Those with a history of depression had more tangles and plaques in the hippocampus than those without. People who were depressed at the time they were diagnosed with Alzheimer's disease had even more pronounced changes in their brains than those whose depression occurred earlier or later. Based on the analyses of cognitive tests that where given to the participants, those with Alzheimer's who had a history of depression also experienced a more rapid decline into dementia than those who did not have depression.