Table 1 Main findings from epidemiological studies on testosterone and cognitive function in men.
From: A Mendelian randomization study of testosterone and cognition in men
Main references | ||||||
|---|---|---|---|---|---|---|
Study design | Exposure | Cognitive function | Author, year | Sample size (men) | Mean age (years) | Main findings |
Observational studies | Serum testosterone | ↑ in older people | Muller, 20054 | 400 | 60.2 | Curvilinear association with verbal memory, which disappears in age subgroups; only associated with better verbal memory in the oldest age group, no association in other age groups. No association with MMSE. |
↑↔ | Hogervorst, 20105 | 257 | 74.4 | Optimal TT associated with better MMSE at baseline, no association with MMSE change or verbal memory | ||
↔ | LeBlanc, 201063 | 1602 | NA | No association with modified mental state examination (3MS), which includes MMSE | ||
↓ | Martin, 20077 | 1195 | 54.3 | Associated with worse verbal memory | ||
RCTs | Testosterone administration | ↔ | Haren, 20059 | 76 | 68.5 | No effect on MMSE |
↔ | Sih, 199710 | 15 | 68 | No effect on verbal memory | ||
↓↔ | Maki, 200713 | 15 | 73.9 | Decreased short-delay verbal memory; no effect on composite verbal memory | ||
↑ | Cherrier, 200511 | 32 | 76 | Increased verbal and spatial memory | ||
↑ | Wahjoepramono, 201512 | 44 | NA | Increased MMSE | ||
Meta-analysis of interventional studies | Androgen deprivation therapy (ADT) | ↓↔ | McGinty, 201414 | 417 | 63.2–71.0 | Prostate cancer patients receiving ADT had worse performance on visuomotor tasks compared to noncancer control groups. No effect on other cognitive domains. |
