Hormone therapy for prostate cancer increases the risk of Alzheimer's disease: a nationwide 4-year longitudinal cohort study.

INTRODUCTION: Androgen-deprivation therapy (ADT) is recognized to be the preferred first-line treatment for advanced prostate cancer. However, the risk-benefit ratio of ADT remains poorly defined and the relationship between androgen depletion and dementia is not clear.

AIM: To investigate the risk of developing Alzheimer's disease (AD) in patients undergoing ADT for prostate cancer.

METHODS: Data from 24 360 prostate cancer patients were collected from the Longitudinal Health Insurance Database of Taiwan. In total, 15 959 patients who underwent ADT were included in the study cohort, and another 8401 patients who did not receive ADT were included as a non-ADT cohort.

RESULTS: During the average 4-year follow-up period, the incidence of AD was 2.78 per 1000 person-years in the non-ADT cohort and 5.66 per 1000 person-years in the ADT cohort. After adjusting for age and all comorbidities, the combined ADT cohort was found to be 1.84 times more likely to develop AD than the non-ADT control group (95%CI 1.33-2.55, p < 0.001).

CONCLUSIONS: The present results suggest that ADT use is associated with an increased risk of developing AD.