Late Life Depression Increases Risk of Dementia

Depression in older people may increase their risk of developing Alzheimer’s disease, according to research from the Framingham Heart Study. Late-life depression has been discovered to be a major risk factor in the development of Alzheimer’s disease and dementia. What is not clear is whether or not those who are susceptible to depression are simply more susceptible to dementia or if one directly causes the other.

While previous studies have had inconclusive results, this is the first to follow a group of aging individuals for nearly 20 years, giving the researchers a longer period of time in which to study the connection between depression and dementia related conditions.

More than 5 million retirement age Americans suffer from depression, which can also affect memory and cognitive skills. The study followed nearly 1000 participants whose average age at the start of the study was 79, none of whom were suffering from symptoms of dementia.

Approximately 13 percent of the participants were suffering from depression at the start of the study. By the time the follow up period had ended, nearly 20 percent of the group had developed dementia, and the study showed that those participants who suffered from depression were 70 percent more likely to develop dementia or Alzheimer’s disease.

A second study of more than 1,200 older people supported the Framingham findings, also finding a connection between depression late in life and the development of dementia related disorders. The study’s results indicated that those older participants who had experienced at least two episodes of late life depression had a doubled risk of developing dementia or Alzheimer’s disease. A third study also out this month measured the effects of depression on the progression of Alzheimer’s, but found no conclusive evidence that symptoms of dementia were accelerated.