Correlation of the P300 evoked potential in depressive and cognitive aspects of aging

The P300 is a long-latency auditory evoked potential highly dependent on cognitive skills. It is believed that cognitive changes caused or not by depressive symptoms may interfere with the P300. Aim: To investigate the influence of aging, cognitive and depression aspects of the P300 latency in elderly people. Methods: Clinical and experimental study with 60 elderly patients with sensorineural hearing loss of mild to moderately severe level, 20 males and 40 females, average age of 71.1. Participants were submitted to the long latency auditory evoked potential, in which the P300 latency (milliseconds) was studied. The cognitive aspects were assessed using the Mini-Mental State Examination (MMSE) and Alzheimer's Disease Assessment Scale (ADAS-Cog). In the assessment of depressive symptoms the Geriatric Depression Scale (GDS-15) was applied. Results: We found a significant positive correlation between latency and age (p = 0.031). There were no significant differences among the P300 latency and the ADAS-Cog (p = 0.584), MMSE (p = 0.199) and GDS (p = 0.541) categories. Conclusion: Aging caused an increase in the P300 latency; however, cognitive performance and the presence of depressive symptoms did not influence the P300 results in this elderly population.