depression and risk of dementia

Last edited 08/2023 and last reviewed 10/2023

Depression and dementia risk

  • Elser et al have investigated the association between depression and subsequent development of dementia (1)

    • a nationwide, population-based, cohort study conducted from April 2020 to March 2023. Participants included Danish citizens from the general population with depression diagnoses who were matched by sex and birth year to individuals with no depression diagnosis. Participants were followed up from 1977 to 2018
      • excluded from analyses were individuals followed for less than 1 year, those younger than 18 years, or those with baseline dementia.
    • study results
      • were 246,499 individuals (median [IQR] age, 50.8 [34.7-70.7] years; 159,421 women [64.7%]) with diagnosed depression and 1,190,302 individuals (median [IQR] age, 50.4 [34.6-70.0] years; 768,876 women [64.6%]) without depression
      • approximately two-thirds of those diagnosed with depression were diagnosed before the age of 60 years (684,974 [67.7%])
      • hazard of dementia among those diagnosed with depression was 2.41 times that of the comparison cohort (95% CI, 2.35-2.47)
        • this association persisted when the time elapsed from the index date was longer than 20 to 39 years (hazard ratio [HR], 1.79; 95% CI, 1.58-2.04) and among those diagnosed with depression in early, middle, or late life (18-44 years: HR,3.08; 95% CI, 2.64-3.58; 45-59 years: HR,2.95; 95% CI, 2.75-3.17; >=60 years: HR,2.31; 95% CI, 2.25-2.38)
        • overall HR was greater for men (HR,2.98; 95% CI, 2.84-3.12) than for women (HR,2.21; 95% CI, 2.15-2.27)
    • study authors concluded:
      • results suggest that the risk of dementia was more than doubled for both men and women with diagnosed depression
      • the persistent association between dementia and depression diagnosed in early and middle life suggests that depression may increase dementia risk

Reference:

  • Elser H et al. Association of Early-, Middle-, and Late-Life Depression With Incident Dementia in a Danish Cohort.JAMA Neurol.Published online July 24, 2023.doi:10.1001/jamaneurol.2023.2309