SAN FRANCISCO, March 24 (UPI) -- Higher symptoms of worsening depression were linked to dementia in a recent study by researchers at the University of California San Francisco, either as an indicator or a symptom of cognitive declines in patients.
The researchers say that while depression has been linked to various forms of dementia in previous studies, the downward trajectory of symptoms linked to increasing cognitive difficulty had not been seen before.
The years-long study found patients without dementia symptoms but who had consistently serious and escalating depression developed higher rates of dementia than those with minimal depressive symptoms.
"While we cannot rule out that depression may foreshadow dementia as an early symptom, or may be an emotional response to cognitive decline, we found an almost twofold increase among those with high-and-increasing symptoms," Dr. Allison Kaup, an assistant adjunct professor at the University of California San Francisco, in a press release. "This suggests that a particular pattern of depressive symptoms may be an independent risk factor."
For the study, published in JAMA Psychiatry, the researchers recruited 2,488 black and white adults, 53.1 percent of whom were women, and had a mean age of 74 at baseline. Of the participants, 62 percent had consistently minimal symptoms of depression, 32.2 percent had moderate and increasing symptoms and 5.8 percent had high and increasing symptoms.
During six years of follow-up, the researchers found 12.3 percent of participants with minimal symptoms developed dementia, while 21.4 percent of those with high and escalating symptoms developed the cognitive condition. Those with mid-level symptoms also had higher rates of dementia, though they were offset when cognitive function level among the groups was compared.
The study's results suggest seniors should be screened more often for depression and depressive symptoms.
"Our results raise the possibility that older adults' cognitive health could be improved with interventions to reduce depressive symptoms, such as psychotherapy or other behavioral interventions, or medications," Kaup said. "This is an important topic for future treatment studies to investigate."