Association between depression and young-onset dementia in middle-aged women

Abstract Background Dementia is associated with older adults; however, it can also affect younger individuals, known as young-onset dementia (YOD), when diagnosed before the age of 65 years. We aimed to conduct a retrospective cohort study involving middle-aged women to investigate the association between premorbid depression and YOD development. Methods We included 1.6 million women aged 40–60 years who underwent health checkups under the Korean National Health Insurance Service and investigated the association between depression and YOD. Results Women with depression had a significantly higher risk of developing YOD than women without depression. Among premenopausal women, those with depression had a 2.67-fold increased risk, whereas postmenopausal women with depression had a 2.50-fold increased risk. Late age at menarche (> 16 years) and young age at menopause (