dementia brain
Alzheimer's Disease and other Dementias

The Depression/Dementia Connection

Editor’s note: Depression can be devastating for the sufferer and his or her loved ones, but when paired with dementia, it can be especially heartbreaking. Here, from the experts at Generations Healthcare, a network of skilled nursing, memory care and rehabilitation facilities in California, is an explanation of the link between depression and dementia, and how to manage it:

Dementia is a group of conditions that impairs the brain, affecting over47.5 million sufferers worldwide and 3 million U.S. cases per year. With sudden memory loss, language changes, memory disorders, personality changes, and impaired reasoning all seemingly effects of the disease, dementia is impossible to ignore as a cultural phenomenon.

What the media hasn’t covered at length is the increasing data pointing to links between depression and dementia. New studies and evidence are exposing a strong link between depression, dementia and Alzheimer’s. (Although the terms “Alzheimer’s” and “dementia” are often used interchangeably, they are different conditions.) The key to predicting and preventing dementia, the baby boomers’ most feared disease, may be staring back at us in the form of America’s most common mental illness, depression.

Signs of depression may be an early indication that dementia is developing in the brain before the telltale signs of memory loss appear. High levels of depression prior to a dementia diagnosis have been linked to more drastic decreases in thinking and memory skills later on. Researchers from Erasmus Medical Center in the Netherlands found that elderly people who developed increasingly worse depressive symptoms were more likely to develop dementia.

Researchers examined 3,325 people, aged 55 and older, as part of a population study dating back to 1990. Their goal was to examine the tentative link between depression and dementia. They found that 21% of people whose depressive symptoms increased over time were eventually diagnosed with dementia. By comparison, only 10% of people with “low symptoms of depression” developed dementia.

High levels of depression prior to a dementia diagnosis were linked to a more drastic decrease in thinking and memory skills later. Depressive symptoms that gradually increase over time appear to be a strong predictor of dementia later in life. Inflammation in the brain is seen in episodes of depression and cognitive decline. Inflammation may be the key to understanding this link.

Another study, published in the journal Neurology, found that people with more symptoms of depression suffer a more rapid decline in thinking and memory skills as they age. The study involved over 1,700 people who had no cognitive or memory problems. Participants were screened every year for symptoms of depression, such as loneliness and lack of appetite, and took tests on their thinking and memory skills for an average period of eight years.