Cognitive Reserve in Parkinson’s Disease: The Effects of Welsh-English Bilingualism on Executive Function

Table 1

Baseline demographics and disease variables.

(a)

Variable-mean value (SD)	Monolingual	Bilingual	Chi squared	Significance	ANOVA	Significance
	Age	71.5 (7.9)					71.3 (10.5)			0.01	.89
Age at diagnosis	64.6 (9.2)	65.2 (13.3)			0.07	.79
Education years	13.0 (2.8)	11.8 (2.3)			5.26	.02
UPDRS motor	20.4 (8.8)	23.1 (12.2)			1.49	.22
HADS depression	3.9 (2.4)	4.3 (3.1)			0.59	.44
HADS anxiety	4.7 (3.1)	5.3 (3.7)			0.78	.37
MMSE	28.6 (2.0)	27.9 (2.4)			3.04	.08
LED	576 (387)	493 (386)			1.171	.28
Anticholinergic cognitive burden	0.47 (1.3)	0.82 (1.3)			1.74	.18
Male	40	31	0.09	.46
Female	17	15

(b)

Variable	Category	Monolingual	Bilingual	Chi squared	Significance	ANOVA	Significance
		Socioeconomic status	(I) Professional					7	1	5.53	.23
(II) Managerial/technical	21		17
(III N) nonmanual skilled	9		8
(III M) manual skilled	14		10
(IV) Partly skilled	6		10
(V) Unskilled	2		0
Education years category	(1) 7–11	20	23	5.02	.08
	(2) 12–15	23	19
	(3) 16–20	14	4
Education level category	(1) Left before 16, no qualification	9	22	16.38	.001
	(2) Secondary only	9	10
	(3) Further education/vocational	29	11
	(4) University & higher degrees	10	3
Hoehn and; Yahr [20]	1	31	32	2.19	.33
	2	19	11
	3 & 4	6	3

Classification based on occupation (64).
Hospital Anxiety and Depression Scale (HADS), Mini-Mental State Examination (MMSE), Unified Parkinson’s Disease Rating Scale (UPDRS), and levodopa equivalent dose (LED).