The secret of preventing memory loss in old age may lie in treating depression and causes of stress early as researchers have confirmed that depression indeed increases the risk of dementia.
Having a higher level of depression symptoms was associated with a more rapid decline in thinking and memory skills, the findings showed.
"These findings are exciting because they suggest depression truly is a risk factor for dementia," said Robert Wilson from Rush University Medical Centre in the US.
"If we can target and prevent or treat depression and causes of stress we may have the potential to help people maintain their thinking and memory abilities into old age," Wilson explained.
The study involved 1,764 people with an average age of 77 who had no thinking or memory problems at the start of the study.
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 of eight years.
During the study, 922 people, or 52 percent of the participants, developed mild cognitive impairment (MCI) and a total of 315 people, or 18 percent, developed dementia.
People who developed mild cognitive impairment and dementia were more likely to have a higher level of symptoms of depression before they were diagnosed.
The study appeared in the journal Neurology.
