Apathy in Parkinson’s Disease: An Electrophysiological Study

Table 4

Logistic regression model of P300a amplitude (in Fz area and in ON period).

Variables	Univariate analysis; (𝑃 value)	Multivariate analysis; (𝑃 value)	Adjusted; odds ratio	95%; confidence intervals
Age	0.054*	0.511
Duration of Parkinson’s disease	0.538
Sex	0.625
Time between treatment and test	0.850
Total dose of dopa therapy	0.993
Hoehn & Yahr score	0.726
Total Webster score	0.182
Axial Webster score	0.451
Lateral Webster score	0.226
Total UPDRS III score	0.166
Axial UPDRS III score	0.312
Verbal fluency (animals)	0.114
Verbal fluency (letter M)	0.090*	0.532
Verbal fluency (boy + fruit names)	0.296
Stroop test (SP)	0.239
Stroop test (SR-SP)	0.949
Wisconsin (number of series)	0.431
Wisconsin (number of mistakes)	0.285
Wisconsin (perseveration percentage)	0.933
FAB	0.102*	0.813
HAD (anxiety)	0.658
HAD (depression)	0.150
Goldberg (anxiety)	0.878
Goldberg (depression)	0.327
Apathy (Starkstein)	0.003*	0.029*	1.67	1.06–2.63

∗Significant 𝑃 values at the 0.1 level.