Earlier Intervention with Deep Brain Stimulation for Parkinson’s Disease

Table 1

Randomized controlled trials for DBS versus BMT in PD.

Study	Target/number	Mean age (yrs)	Baseline characteristic in the “off” state	Mean disease duration (yrs)	Follow-up (mos)	Outcome/conclusion
Deuschl et al. 2006 [40]	STN + BMT: 78; BMT: 78	STN + BMT: 60.5; BMT: 60.8	H & Y; STN + BMT: 3.7, BMT: 3.8; UPDRS-III; SNT + BMT: 48.0, BMT: 46.8	>5	6	(i) UPDRS-III: 41% improvement in DBS versus 0% in the BMT ().; (ii) PDQ-39: STN resulted in 14 % improvement.
Schüpbach et al. 2007 [41]	Bilateral STN + BMT: 10; BMT: 10	Bilateral STN + BMT: 48.4; BMT: 48.5	H & Y; <3; UPDRS-III; Bilateral STN + BMT: 32.7; BMT: 25.3	Bilateral STN + BMT: 7.2; BMT: 6.4	18	(i) UPDRS-III: 69% improvement in DBS versus worsening in BMT ().; (ii) PDQ-39: 24% improvement in DBS versus 0% in BMT ().; (iii) Levodopa dose: reduced by 57% in the DBS versus 12% in the BMT ().
Weaver et al. 2009 [42]	Bilateral STN/GPi: 121; BMT: 134	Bilateral STN/GPi: 62.4; BMT: 62.3	H & Y; Bilateral STN/GPi: 3.4,; BMT: 3.3; UPDRS-III; Bilateral STN/GPi: 43; BMT: 43.2	Bilateral STN/GPi: 10.8; BMT: 12.6	6	(i) UPDRS-III: 71% of DBS patients experienced clinically meaningful motor function versus 32% of BMT patients ().; (ii) PDQ-39: DBS group had significant improvement ().
Williams et al. 2010 [43]	Bilateral STN/GPi: 183; BMT: 183	DBS: 59; BMT: 59	H & Y; DBS: 3.1, BMT: 3.2; UPDRS-III; DBS: 47.6, BMT: 48.6	DBS: 11.5; BMT: 11.2	12	(i) UPDRS-III: 36% improvement in the DBS group versus 2% in BMT ().; (ii) PDQ-39: mean improvement compared with baseline was 5.0 for the DBS group versus 0.3 points in the BMT ().
Schuepbach et al. 2013 [44]	SNT + BMT: 124; BMT: 127	SNT + BMT: 52.9; BMT: 52.2	H & Y; <3; UPDRS-III; STN + BMT: 33.2; BMT: 33	STN + BMT: 7.3; BMT: 7.7	24	(i) UPDRS-III: 56% improvement in the DBS group versus 4% in BMT ().; (ii) PDQ-39: 26% improvement in the DBS group versus no improvement in the BMT group ().; (iii) Levodopa induced motor complications: 61% improvement in the DBS group versus no improvement in the BMT group ().
Charles et al. 2014 [39]	STN + BMT: 15; BMT: 15	STN + BMT: 60; BMT: 60	H & Y; STN + BMT: 2, BMT: 2; UPDRS-III; STN + BMT: 25.3; BMT: 25.6	STN + BMT: 2.2; BMT: 2.1	24	(i) UPDRS-III: mean scores were not significantly different on or off therapy.; (ii) Medication requirements in the DBS + BMT group were lower at all time points.

DBS: Deep Brain Stimulation; SNT: subthalamic nucleus; GPi: globus pallidus interna; BMT: best medical therapy.