Table 1. Demographic and clinical measures.

	Control	PD	Group*
# of subjects	62	72
Sex (males.females)	33/29	35/37	0.608
Age at baseline, yr (SD)	66.2 (10.2)	66.3 (9.5)	0.936
Education, yr (SD)	15.7 (2.8)	15.0 (3.2)	0.226
Disease duration (yr, SD)	-	4.5 (4.5)	-
Hoehn and Yahr	-	1.7 (0.7)	-
LEDD	-	669 (464)	-
MDS-UPDRS part I	2.9 (2.9)	7.4 (4.8)	<0.0001
MDS-UPDRS part II	0.4 (1.5)	7.4 (6.2)	<0.0001
MDS-UPDRS part III	3.2 (3.2)	21.5 (14.7)	<0.0001
MoCA	25.6 (2.4)	24.5 (3.7)	0.450
HDRS	2.7 (2.6)	5.0 (4.4)	<0.0001
PDQ39	2.7 (2.7)	11.5 (8.4)	<0.0001

Parenthetical terms are standard deviations (SD).

^*P value for sex is the group difference at baseline using the Chi-square test. The p values for age and education years are group differences at baseline using the two-tailed Student t test. P values for UPDRS-I, -II, -III, MoCA, HDRS, and PDQ39 are group difference at baseline using a mixed effects model adjusting for age, sex, and education years.

Abbreviations: HDRS, Hamilton Depression Rating Scale; LEDD, levodopa equivalent daily dosage; MDS-UPDRS, the Movement Disorders Society Unified Parkinson's Disease Rating Scale, I = non-motor activities of daily living, II = motor activities of daily living, and III = motor evaluation by a trained rater; MoCA, Montreal Cognitive Assessment; PDQ-39, 39-item Parkinson's Disease Questionnaire; yr, years.

Bold and italic font indicates significance after Bonferroni correction.