Depression as a Driving Force for Low Time in Therapeutic Range and Dementia in Patients With and Without Atrial Fibrillation.

Both time in therapeutic range (TTR) for anticoagulation and depression are associated with dementia risk. The purposes of this study were to examine the impact of depression on TTR and to describe the partitioned contribution of depression and TTR on long-term dementia risk. We studied 14,953 patients anticoagulated with warfarin (target INR 2-3) for atrial fibrillation (AF), venous thromboembolism (VTE), or a mechanical heart valve from 2003 to 2015. We excluded patients with a diagnosis of dementia before or within 6 months of warfarin initiation. We examined the association of depression with TTR using finite mixture modeling and logistic regression and utilized multivariable Cox hazard regression to determine the association of TTR and depression with incident dementia at 3 and 13 years. Forty % (n = 6055) of patients were diagnosed with depression before or while on warfarin. Patients with depression had significantly lower TTR and were 1.37 times more likely to have TTR