Delayed latencies of auditory evoked potential P300 are associated with the severity of Parkinson's disease in older patients.
Electrophysiological methods could provide important information about the neurophysiological status in Parkinson's disease (PD).


OBJECTIVE
To investigate the prolonged auditory P300 latency in PD and its association with the disease clinical stage.


METHODS
Clinical profiles of 44 patients were evaluated and those in initial and advanced stages of PD were identified. The frequency of altered latencies, median of latencies in each stage, and correlation between latencies and motor and non-motor clinical features were analyzed. Latencies were considered altered when they were more than two standard deviations from the mean of controls, per age group.


RESULTS
It was verified 10% of alterations in initial stages and 31% in advanced. There was correlation between latencies and non-motor clinical features. Subjects older than 65, in advanced stages, presented a significant increase of latencies.


CONCLUSIONS
There was an association between PD severity and P300 prolonged latencies among subjects 65 years old or older.
Divisão de Neurologia e Epidemiologia, Universidade Federal da Bahia, Salvador, BA, Brazil.
Marcia da
Md
Silva Lopes
Divisão de Neurologia e Epidemiologia, Universidade Federal da Bahia, Salvador, BA, Brazil.
Ailton de
Ad
Souza Melo
Departamento de Fonoaudiologia, Instituto de Ciências da Saúde, Universidade Federal da Bahia, Salvador, BA, Brazil.
Ana Caline
AC
Nóbrega
D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology; D016022:Case-Control Studies; D003071:Cognition / Q000502:physiology; D003430:Cross-Sectional Studies; D018913:Event-Related Potentials, P300 / Q000502:physiology*; D016057:Evoked Potentials, Auditory, Brain Stem / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000503:physiopathology*; D011930:Reaction Time / Q000502:physiology; D012720:Severity of Illness Index; D018709:Statistics, Nonparametric; D013997:Time Factors