SupplementaryTable 1|Motor effects of STN and GPi stimulation on axial symptoms in controlled (all available studies) and uncontrolled open-label studies (with a follow-up longer than 5 and 3 years, respectively)

Study / Design / Follow-up (years) / # of patients / UPDRS-IIIa / Postural stability / Gait / FOGe
STN DBS
DBS for PD study group, 20011 / Parallel, open (with a double-blind, randomized, crossover part at 3 months) / 0.5 / 96 / –51.3 / –50.0 / –55.6* / NA
Anderson et al., 20052 / Randomized, parallel, double-blind; comparing STN and GPi** / 1 / 12 / –48 / Axial scoreb:–43.8 / NA
Vercruysse et al., 20143 / Prospective, controlled / 1 / 24 / –31 / NA / NA / –66
Krack et al., 20034 / Prospective, uncontrolled, open-label / 5 / 42 / –53.7* / –44.0* / –51.6* / +300.0*
Schüpbach et al., 20055 / 5 / 30 / –49.5* / Axial scorec: –39.7* / NA
Piboolnuraket al., 20076 / 5 / 17 / –34.6* / –5.5 / –15.8 / NA
Wider et al., 20087 / 5 / 21 / –29.7* / Axial scored: +1.6 / NA
Gervais-Bernard et al., 20098 / 5 / 23 / –54.7* / –17.5 / –37.0 / NA
Romito et al., 20099 / 5 / 20 / –54.2* / –44.4 / –50.0* / –80.5*
Moro et al., 201010 / 5–6 / 35 / –45.0* / –42.9* / –36.7* / NA
Fasano et al., 201011 / 8 / 20 / –39.0* / +23.5 / –40.9* / NA
Zibetti et al., 201112 / ≥9 / 14 / –42.5* / 00.00 / –36.0* / +31.3
Castrioto et al., 201113 / 10 / 18 / –22.7* / +10.0 / 00.00 / –50.0*
Rizzone et al., 201414 / 11 / 26 / –35.8* / 00.00 / –30.0 / +114.3
GPi DBS
DBS for PD study group, 20011 / Parallel, open, (with a double-blind, randomized, crossover part at 3months) / 0.5 / 38 / –33.3 / –36.4 / –50.0* / NA
Anderson et al., 20052 / Randomized, parallel, double-blind comparing STN and GPi** / 1 / 11 / –39 / Axial scoreb:–40.0 / NA
Durifet al.,200215 / Prospective, uncontrolled, open-label / 3 / 6, unilateral in 1 / –32 / NA / NA / NA
Lyons et al., 200216 / 4 (average) / 9, unilateral in 3 / –37* / –36.8 / –52.2* / NA
Volkmann et al., 200417 / 5 / 6 / –23.2 / NA / –19.0 / +17.0
Rodriguez-Oroz et al., 2005§18 / 3–4 / 20 / –38.7* / –26.1 / –28.0* / +1.7
Moro et al., 2010§10 / 5–6 / 16 / –35.1* / –36.4 / –17.4 / +20.8

Values are given as percentage variation between the longest available follow-up and the baseline. Motor outcomes refer to the no-medication state/stimulation ON condition (negative values indicate a reduction in the scores and, therefore, an improvement; positive values indicate an increase and, therefore, worsening of the scores).Abbreviations: DBS, deep brain stimulation; FOG, freezing of gait; GPi, globus pallidum pars interna; NA, not available; PD, Parkinson disease; STN, subthalamic nucleus; UPDRS-III, Unified PD Rating Scale–Motor section.*Significant compared with the values before surgery in the same drug condition; all the other comparisons were not significant. **Patients in the STN group with disease duration 5 years longer than GPi group.§Some of the centres participated in this extension of a trial originally conducted by 18 centres designed to blindly assess the effect of stimulation at 3 months post-operatively.1aEfficacy is evaluated with stimulation turned on, but without antiparkinsonian medication.bBased on the sum of the UPDRS-III items 18, 28–30.cAxial score defined as the sum of the UPDRS-III items 18, 27, 28, 29, and 30.dAxial score defined as the sum of the UPDRS-III items 27, 28, 29, and 30.eBased on UPDRS-II (activities of daily living) evaluated with stimulation turned on and with antiparkinsonian medications.

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