Later-life depression and dementia (USA)
Researchers from the University of Washington, Seattle have found that depression occurring after age 50 years (termed later-life depression) is associated with an increased risk for dementia.
More than 2000 subjects from Seattle’s Group Health Cooperative were enrolled in a study that recruited people from 1994 to 2004. Participants were aged 65 years or older and free of dementia at the outset; they were followed every 2 years for up to 15 years.
Depressive states were also assessed initially, based on the Centre for Epidemiologic Studies Depression Scale. Subjects with a score of 11 or more were considered to have significant depressive symptoms.
Results showed that participants with a depression score of more than 11 had a 71 per cent higher risk for dementia. Early-life depression (occurring before age 50 years) did not have any bearing on risk for developing dementia.
Researchers speculate that later-life depression might actually be an early manifestation, rather than a cause, of dementia. If that is the case, earlier intervention might be beneficial in improving patient outcomes and slowing the development of dementia. However without further research and intervention studies, this is not known for certain.
To read the abstract from the Archives of General Psychiatry online, go towww.archpsyc.ama.assn.org.