Table 2.

Prevalence of six risk factors for PD

Putative risk factor	All cases (n = 775)	0/1 risk factor (n = 688)	≥2 risk factors (n = 87)
Olfactory dysfunction % (n)	3.9 (30)	2.2 (15)	17.2 (15)
REM sleep behavior disorder % (n)	13.3 (103)	9.7 (67)	41.4 (36)
Constipation % (n)	9.7 (75)	7.3 (50)	28.7 (25)
Cognitive impairment (MMSE≤24 points) % (n)	2.8 (22)	1.2 (8)	16.1 (14)
Depression (CES-D ≥16 points) % (n)	12.0 (93)	4.5 (31)	71.3 (62)
Anxiety (HADS-A ≥8 points) % (n)	8.8 (68)	1.9 (13)	63.2 (55)

REM, rapid eye movement; MMSE, Mini-Mental State Examination; CES-D, Center for Epidemiologic Studies Depression Scale; HADS-A, Hospital Anxiety and Depression Scale –subscale Anxiety.