title: P300 Amplitude in Alzheimer's Disease: A Meta-Analysis and Meta-Regression.
abstract: Alzheimer's disease accounts for 60% of all dementia. Numerous biomarkers have been developed that can help in making an early diagnosis. The P300 is an event-related potential that may be abnormal in Alzheimer's disease. Given the possible association between P300 amplitude and Alzheimer's disease and the need for biomarkers in early Alzheimer's disease, the main purpose of this meta-analysis and meta-regression was to characterize P300 amplitude in probable Alzheimer's disease compared to healthy controls. Using online search engines, we identified peer-reviewed articles containing amplitude measures for the P300 in response to a visual or auditory oddball stimulus in subjects with Alzheimer's disease and in a healthy control group and pooled effect sizes for differences in P300 amplitude between Alzheimer's disease and control groups to obtain summary effect sizes. We also used meta-regression to determine whether age, sex, educational attainment, or dementia severity affected the association between P300 amplitude and Alzheimer's disease. Twenty articles containing a total of 646 subjects met inclusion and exclusion criteria. The overall effect size from all electrode locations was 1.079 (95% confidence interval=0.745-1.412, P<.001). The pooled effect sizes for the Cz, Fz, and Pz locations were 1.226 (P<.001), 0.724 (P=.0007), and 1.430 (P<.001), respectively. Meta-regression showed an association between amplitude and educational attainment, but no association between amplitude and age, sex, and dementia severity. In conclusion, P300 amplitude is smaller in subjects with Alzheimer's disease than in healthy controls.
authors.affiliation: Department of Psychology, Brigham Young University, Provo, UT, USA The Neuroscience Center, Brigham Young University, Provo, UT, USA dawson_hedges@byu.edu.
authors.forename: Dawson
authors.initials: D
authors.lastname: Hedges
authors.affiliation: Department of Psychology, Brigham Young University, Provo, UT, USA.
authors.forename: Rebecca
authors.initials: R
authors.lastname: Janis
authors.affiliation: Department of Psychology, Brigham Young University, Provo, UT, USA.
authors.forename: Stephen
authors.initials: S
authors.lastname: Mickelson
authors.affiliation: The Neuroscience Center, Brigham Young University, Provo, UT, USA.
authors.forename: Cierra
authors.initials: C
authors.lastname: Keith
authors.affiliation: The Neuroscience Center, Brigham Young University, Provo, UT, USA.
authors.forename: David
authors.initials: D
authors.lastname: Bennett
authors.affiliation: Department of Psychology, Brigham Young University, Provo, UT, USA.
authors.forename: Bruce L
authors.initials: BL
authors.lastname: Brown
mesh_terms: D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000175:diagnosis* / Q000453:epidemiology / Q000503:physiopathology*; D015897:Comorbidity; D004522:Educational Status; D004569:Electroencephalography / Q000706:statistics & numerical data*; D018913:Event-Related Potentials, P300; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D012044:Regression Analysis; D015203:Reproducibility of Results; D012307:Risk Factors; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D017678:Sex Distribution
keywords: Alzheimer’s disease; EEG; P300 amplitude; event-related potentials; meta-analysis