Risk for Incident Dementia Increased With Diagnosed Depression

Increased risk seen when time from index date was longer than 20 to 39 years and for diagnosis of depression in early, middle, late life

By Elana Gotkine HealthDay Reporter

MONDAY, July 24, 2023 (HealthDay News) — Men and women with diagnosed depression have an increased risk for dementia, according to a study published online July 24 in JAMA Neurology.

Holly Elser, M.D., Ph.D., from Aarhus University in Denmark, and colleagues examined the associations between early-, middle-, and late-life depression and incident dementia in a nationwide cohort study involving Danish individuals. Data were included from 246,499 individuals with diagnosed depression and 1,190,302 without depression.

The researchers found that 67.7 percent of those diagnosed with depression were diagnosed before the age of 60 years. Relative to the comparison cohort, those diagnosed with depression had a 2.41 times higher hazard of dementia. When the time elapsed from the index date was longer than 20 to 39 years (hazard ratio, 1.79) and among those diagnosed with depression in early, middle, or late life, the association persisted (hazard ratios, 3.08, 2.95, and 2.31 for 18 to 44 years, 45 to 59 years, and 60 years and older, respectively). Men had a greater hazard ratio for dementia than women (2.98 versus 2.21).

“Findings support our hypothesis that associations would persist regardless of time since depression diagnosis or the age at which depression was diagnosed,” the authors write. “Our results therefore suggest that depression is not only an early symptom of dementia but also that depression is associated with an increase in dementia risk.”

One author disclosed receiving fees from Peabody Arnold and having a patent for use of glecaprevir/pibrentasvir; a second author disclosed ties to Amgen.