Depression May Raise Dementia Risk

People who are depressed have a higher risk of dementia in later life, a new study concludes. The research was based on data about 949 older adults from a larger, long-running study. Their average age was 79. Tests showed that 125 had depression. Researchers kept track of them for up to 17 years. In that time, 164 people developed dementia. About 22% of those who were depressed at the start of the study developed dementia. This compares with 17% of those who were not depressed. People who were depressed also had more heart disease and other factors that increase the risk of dementia. Researchers adjusted their data for those differences. After the adjustment, they found that depressed people were about 70% more likely to develop dementia. The reason is unclear. Researchers said being depressed can inflame the brain and increase its output of certain proteins.