Nonmotor Symptoms Groups in Parkinson's Disease Patients: Results of a Pilot, Exploratory Study

Table 2

Results of the exploratory factor analysis.

Items	Factor 1	Factor 2	Factor 3	Factor 4	Factor 5
Sleep quality (PDSS)	0.789
Noct. restlessness (PDSS)	0.839
Off-related problems (PDSS)	0.636
Daytime somnolence (PDSS)	0.538
Nocturia (PDSS)		0.839
Noct. Activity (actigraphy)		0.654
GU symptoms (NMSQ)			0.935
GI Motility disorders (NMSQ)			0.939
Noct. Psychosis (PDSS)				0.572
Sialorrhea (UPDRS)				0.809
Dysphagia (UPDRS)				0.668
MADRS					0.911
NPS symptoms (NMSQ)					0.866
Variance explained by factor	27.6	13.2	11.9	9.8	8.0

GU: genitourinary; GI: gastrointestinal; MADRS: montgomery-Asberg depression Rating scale; NPS: neuropsychiatric symptoms.