A recent Kaiser Permanente funded study conducted by researchers in California hoped to find a direct link between why chronic depression sufferers are more likely to develop dementia and Alzheimer’s disease later in life than people who have never suffered from depression.
In their study researchers wanted to determine if dementia is related to depression or merely an early sign of memory loss.
According to the study the leading cause of dementia is still Alzheimer’s disease while the second-leading cause is impaired blood supply to the brain, better known as vascular dementia.
Study researcher Rachel Whitmer tells the Wall Street Journal:
“It’s quite clear depression late in life can be an early sign of Alzheimer’s. There’s a lot of debate whether [depression] is really a risk factor for dementia, or if it just shows up.”
Kaiser Premanente points out that various risk factors can contribute to dementia including:.
– People with more belly fat in middle age had higher rates of dementia when they reached old age. This held true even for people whose overall body weight was considered normal.
– People who smoked in middle age had an increased risk of developing dementia and Alzheimer’s disease later on. People who smoked two packs or more daily had more than double the risk.
– People with high cholesterol in middle age had an increased risk of developing dementia and Alzheimer’s disease in old age
Published in the May issue of Archives of General Psychiatry the study found that late-in-life depression seems most likely to be a sign of Alzheimer’s disease, while chronic depression tends to increase the chances of vascular dementia.
Researchers believe that treatment for depression in midlife could help prevent dementia.
The study examined 13,535 long-term Kaiser Permanente members and then examined people who were depressed at different stages of their life. The study started in 1964 through 1973 with patients examined again from 1994 through 2000 to determine the levels of depression and other lifestyle choices that may have led to dementia and Alzheimer’s Disease.
The study found that 20.7% of patients who developed dementia did not suffer from depression while depression sufferers made up 23.5% of dementia sufferers, specifically if they had developed depression in midlife.
The study also found that various other factors played a key part in developing Alzheimer’s and dementia such as smoking, diabetes, high cholesterol and belly fat.
While a direct link has not been found between depression and the loss of memory, this new study at least shows increased risks which should make some depression sufferers realize the importance of proper intervention during the early stages of their depression.