A pilot study to explore the effect of udenafil on cerebral hemodynamics in older adults.

Objective: Phosphodiesterase‐5 inhibitors (PDE5Is) enhance vasodilation. We investigated the effects of PDE5I on cerebral hemodynamics during cognitive tasks using functional near‐infrared spectroscopy (fNIRS). Methods: This study used a crossover design. Twelve cognitively healthy men participants (mean age, 59 ± 3 years; range, 55–65 years) were recruited and randomly assigned to the experimental or control arm, then the experimental and control arm were exchanged after 1 week. Udenafil 100 mg was administered to participants in the experimental arm once daily for 3 days. We measured the fNIRS signal during the resting state and four cognitive tasks three times for each participant: at baseline, in the experimental arm, and in the control arm. Results: Behavioral data did not show a significant difference between the experimental and control arms. The fNIRS signal showed significant decreases in the experimental arm compared to the control arm during several cognitive tests: verbal fluency test (left dorsolateral prefrontal cortex, T = −3.02, p = 0.014; left frontopolar cortex, T = −4.37, p = 0.002; right dorsolateral prefrontal cortex, T = −2.59, p = 0.027), Korean‐color word Stroop test (left orbitofrontal cortex, T = −3.61, p = 0.009), and social event memory test (left dorsolateral prefrontal cortex, T = −2.35, p = 0.043; left frontopolar cortex, T = −3.35, p = 0.01). Interpretation: Our results showed a paradoxical effect of udenafil on cerebral hemodynamics in older adults. This contradicts our hypothesis, but it suggests that fNIRS is sensitive to changes in cerebral hemodynamics in response to PDE5Is. [ABSTRACT FROM AUTHOR]

Copyright of Annals of Clinical & Translational Neurology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)