ADT linked to higher risk of dementia and/or Alzheimer disease in patients with prostate cancer

Androgen-deprivation therapy (ADT) increases the risk that a patient with prostate cancer will develop dementia and/or Alzheimer disease, according to a systematic review and meta-analysis published in the Journal of Urology.¹

Compared with patients not receiving ADT, patients treated with ADT had a 21% higher risk of new onset dementia (all cause; HR, 1.21; 95% CI, 1.11-1.33). The risk of Alzheimer disease among patients receiving ADT was 16% higher (HR, 1.16; 95% CI, 1.09-1.24) compared with those not undergoing the treatment.

The increased risk of dementia (all cause) was more pronounced with longer ADT duration (≥12 months); however, treatment length did not have a significant impact on Alzheimer risk.

“Based on these findings, we recommend routine monitoring of cognitive function in patients receiving ADT. In addition, mental/cognitive status assessment should be performed in all patients planned for ADT. Adequate patient counseling about these potential side effects of ADT should be part of the decision making and follow-up strategy,” the authors wrote in their conclusion.

Using the PubMed and Web of Science databases from January 1 to 3, 2020, the investigators performed a systemic review and meta-analysis of studies that examined the rates of dementia and/or Alzheimer disease in patients with prostate cancer who either received or did not receive ADT. Overall, the investigators selected 14 studies for their research. For their study, the definition of all cause dementia included Alzheimer disease.

Among patients with prostate cancer receiving ADT for ≥12 months, the risk of dementia (all cause) was 36% higher (HR, 1.36; 95% CI, 1.07-1.72) versus those not receiving ADT. The risk of dementia (all cause) in patients treated with ADT for <12 months was 6% greater than those not receiving ADT; however, the difference was not statistically significant (HR, 1.06; 95% CI, 0.77-1.28).

Lower ADT exposure was not associated with significantly lower risk of Alzheimer disease. The risk of Alzheimer disease with ADT was increased by 39% for those with exposure ≥12 months (HR, 1.39; 95% CI, 0.69-2.79) and 21% for those with exposure <12 months (HR, 1.21; 95% CI, 0.97-1.51), compared to patients not receiving ADT.

In their article, the investigators noted limitations to their research, with the primary being the “retrospective nature of the studies included.” Other key limitations included differences in intervention groups, control groups, and outcomes based on the individual designs of the specific studies.

In their conclusion, the researchers noted that prospective studies are needed to further support the cognitive function monitoring and counseling they recommend based on their study results.

They also noted that, “All variables that have a potential influence on outcomes should be considered to perform adjusted analysis in future studies (ie, the risk factors of dementia in the general population as well as ADT type and duration of ADT). Moreover, there are different types and different pathophysiologies of dementia, and the ADT effect on these different types of dementia should be assessed.”

Reference

1. Motlagh RS, Quhal F, Mori K, et al. The risk of new onset dementia and/or Alzheimer disease among patients with prostate cancer treated with androgen deprivation therapy: a systematic review and meta-analysis. J Urol. 2021;205(1):60-67. doi: 10.1097/JU.0000000000001341