Mental health symptoms as preclinical indicators of dementia: a Whitehall II cohort study

Changes in mental health symptoms, and their timing in the preclinical period of dementia, are not well characterised.

We followed 5,495 Whitehall II participants (median age 68.5; 72.1% male) from their mental health symptoms assessment using the Clinical Interview Schedule-Revised (CIS-R) starting in 2012/13 to dementia diagnosis, death, or 2024. Linear mixed effects regression assessed CIS-R score changes preceding dementia. Flexible parametric models estimated associations of mental health symptoms with dementia.

Total CIS-R score increased (2.56 points [0.85-4.27]) in the 12 years preceding dementia. Having any mental health condition was associated with dementia in the short-term (HR at 3 years=4.04 [2.53-6.50]) but not the long-term (HR at 6 years=1.26 [0.63-2.49]). This pattern held for severe mental health conditions, concentration problems, depression, irritability, fatigue, anxiety, and worry.

Awareness of mental health symptoms as preclinical indicators of dementia in the short-term may support timely diagnosis of dementia.