Table 6.

Demographic characteristics of patients in previous studies of bilateral subthalamic nucleus stimulation in PD.

Study	N	F/U (Months)	Mean Age at Surgery (Years)	Mean Disease Duration before Surgery (Years)	Mean “off” HYRS
Limousin et al. [58]	20	12	56 ± 8	14 ± 5	4.6 ± 0.5
Ostergaard et al. [59]	26	12	59 ± 8 (30–75)	15 ± 5	3.7
Simuni et al. [60]	12	12	58 ± 11	12 ± 4	3.8
Thobois et al. [61]	14	12	56.9 ± 6	13.5 ± 4.4	3.6
Vesper et al. [62]	38	12	55.6 (47–72)	13	3.5
Vingerhoets et al. [63]	20	21 ± 8	63 ± 8	16 ± 5	*
Volkmann et al. [64]	16	12	60.2 ± 9.8	13.1 ± 5.9	*
Herzog et al. [65]	20	24	60 ± 6	15 ± 5	3.7
Krause et al. [66]	24	29.8 ± 8.5	57.7	14.4 ± 5.8	4.3
Fraix et al. [67]	24	12	55.7 ± 7.3	16.3 ± 5.4	4.5
Kleiner-Fisman et al. [68]	25	24	57.2 ± 11.7	13.4 ± 4.3	*
Krack et al. [69]	42	60	55 (34–68)	14.6 ± 5	*
Romito et al. [70]	33	25.7 ± 13.5	56.8 ± 7.1	13.8 ± 5.5	*
Visser-Vandewalle et al. [71]	20	48	60.9 ± 8.1	15.0 ± 4.4	*
Rodrguez-Oroz et al. [72]	10	48	62.0 (53–73)	13 (4–23)	*
Rodrguez-Oroz et al. [73]	49	48	*	*	*
Wider et al. [74]	37	60	64.9 ± 7.6	14.4 ± 4.9	*
Gervais-Bernard et al. [75]	23	48	55.1 ± 7.2	12.9 ± 3.2	*
Castrioto et al. [26]	18	120	52.9 ± 7.9	13.4 ± 4.8	*
Weaver et al. [76]	70	36	60.7 ± 8.9	11.3 ± 4.7	3.3 ± 0.8
Li et al. [77]	195	60	58.2 ± 10	6.8 (5–15)	*
Tabbal et al. [78]	72	6	48.4 ± 9.8 (28–69)	14.5 ± 6.5 (4–29)	*
This study	20	12	61.1±8.7 (48–82)	11.7 ± 6.4 (5–30)	3.6 ± 0.7 (2.5–5)

N: number of patients; F/U: duration of follow-up; HYRS Hoehn and Yahr Rating Scale; PD: Parkinson’s disease; UPDRS: Unified Parkinson’s Disease Rating Scale; *: no available data