Androgen Deprivation Therapy and the Risk of Dementia in Patients With Prostate Cancer

PurposeRecent observational studies have associated the use of androgen deprivation therapy (ADT) with an increased risk of dementia and Alzheimer’s disease, but these studies had limitations. The objective of this study was to determine whether the use of ADT is associated with an increased risk of dementia, including Alzheimer’s disease, in patients with prostate cancer.Patients and MethodsUsing the United Kingdom’s Clinical Practice Research Datalink, we assembled a cohort of 30,903 men newly diagnosed with nonmetastatic prostate cancer between April 1, 1988 and April 30, 2015, and observed them until April 30, 2016. Time-dependent Cox proportional hazards models were used to estimate adjusted hazard ratios with 95% CIs of dementia associated with the use of ADT compared with nonuse. ADT exposure was lagged by 1 year to account for delays associated with the diagnosis of dementia and to minimize reverse causality. Secondary analyses assessed whether the risk varied with cumulative duration of use and b...