Elderly people with symptoms of depression are more likely than those without depression to develop mild cognitive impairment (MCI) within six years, according to new study results.

Researchers at the San Francisco VA Medical Center and the University of California looked at 2,220 participants in the Cardiovascular Health Study, a longitudinal prospective study of adults 65 and older and measured the elderly subjects’ depressive symptoms using a standard depression scale. Six years later, a team of dementia experts found that 19.7% of subjects with moderate to high depression had developed MCI. Only 10% of subjects with no depressive symptoms went on to develop MCI, and 13.3% with low depressive symptoms had cognitive impairment.

Researchers noted that the findings were consistent among men and women, the younger and the older, and among subjects with and without vascular disease. In addition, the study showed that the greater the degree of depression, the more likely the impairment.

“This is important, because mild cognitive impairment often precedes dementia,” said Deborah Barnes, a mental health researcher at SFVAMC and lead author of the study report. Approximately 50% of patients diagnosed with MCI go on to develop dementia within three years, according to study findings.