Cognitive effects of long-term androgen deprivation therapy in older men with prostate cancer

Androgen deprivation therapy (ADT) is a common treatment for prostate cancer (PCa), with increasing numbers of men on ADT for longer. Limited evidence suggests ADT impacts cognition. This study addressed gaps in the literature by focusing on older men with PCa and assessing ADT usage longer than 1 year.

This study of 133 men ≥65 years of age with PCa included two groups: (1) men on ADT for 1-3 years (ADT-exposed), and (2) a comparison group of men with PCa not on ADT (ADT-unexposed). Group comparisons on individual neuropsychological test scores are reported, as well as effect sizes (Cohen's d).

Half (n = 67) of the sample was ADT-exposed and half (n = 66) were unexposed. The average age was 72 years, most were White, and over 50% had at least secondary education. There were no statistically significant differences between groups by age, race, or education. Unadjusted analyses showed the ADT-exposed group, compared with the ADT-unexposed group, performed significantly lower in domains of verbal learning (d = 0.45-0.52, p = 0.01 to <0.01), verbal recall (d = 0.33-0.54, p = 0.06 to <0.01), and possible effects in visuospatial construction (d = 0.33, p = 0.08 to 0.06). When controlling for age and education, similar patterns emerged. The ADT exposed-group performed significantly lower in domains of verbal learning (d = 0.45-0.52, p = 0.06 to 0.03) and verbal recall (d = 0.33-0.54, p = 0.11 to 0.03), and possible effects in visuospatial construction d = 0.33, p = 0.18 to 0.13.

This study suggests long-term ADT exposure impacts verbal learning, verbal recall, and possibly visuospatial abilities in older men (≥65) with PCa. The potential cognitive effects of ADT should be discussed with older patients considering long-term use of ADT.