[P300 cognitive event-related potentials in the diagnosis and classification of possible Alzheimer-type...

The value of the P300 cognitive event-related potential in the diagnosis of Alzheimer subtype neurocognitive disorders is still incipient. Recent studies suggest that combining it with neuropsychological tests by cognitive domains would allow an objective and early characterisation of the cognitive impairment in its initial stages.

To characterise the electrophysiological patterns in the P300 potential that obtain a discriminatory value for the diagnosis and classification of the neurocognitive disorders with a possible Alzheimer-type aetiology.

This study examines 39 patients classified, according to the DSM-5, with possible Alzheimer-type minor and major neurocognitive disorders, aged between 50 and 85 years, and 53 control subjects with normal cognitive functions. The P300 potential is registered in the auditory mode, oddball paradigm and centroparietal recording.

P300 latency is significantly prolonged in subjects with neurocognitive disorder; there are significant differences in the mean values and confidence intervals between healthy controls and patients. No significant differences are obtained in P300 latency between groups with minor and major neurocognitive disorder. The mean amplitude value decreases in neurocognitive disorder, and the P300 amplitude logarithm of the control groups and those with minor and major neurocognitive disorder reaches significantly different mean values and confidence intervals.

The parameters quantified in the P300 potential can be used as complementary biomarkers to classify the presence and level of cognitive dysfunction with a possible Alzheimer-type aetiology.