Table 2.
Studies assessing cognitive change in PD patients after GPi DBS.
| Author, year | N | F/u (mo) | Controlled | Status of stimulation/medication at cognitive assessment | Improved cognitive measure(s) | Worsened cognitive measure(s) | Unchanged cognitive measure(s) |
|---|---|---|---|---|---|---|---|
| Ardouin et al., 1999 [25] | 13 | 3–6 | No | ON/inconsistent | E | L | GC, E, PS |
| Jahanshahi et al., 2000 [63] | 6 | 12 | No | ON and OFF/OFF | None | None | E, A/C, PS, M, |
| Pillon et al., 2000 [60] | 13 | 12 | No | ON and OFF/75% OFF | None | None | E, PS, L, M |
| Trépanier et al., 2000 [87] | 4 | 6 | No | ON/ON | None | None | A/C, M, V, L, E |
| Rothlind et al., 2007 [50] | 14 | 21 | No | ON/ON | None | L | A/C, E, L, V, M |
| Fields et al., 1999 [74] | 6 | 5 | No | ON/ON | M | None | GC, E, A/C, V, L, M |
| Tröster et al., 1997 [66] | 9 | 3 | No | ON/ON | None | V, L | GC, E, A/C, V, M, L |
| Tröster et al., 2017 [35] | 136 | 12 | No | ON/not specified | None | L, A/C | GC, A/C, E, M |
| Vingerhoets et al., 1999 [76] | 20 | 3 | No | ON/ON | None | None | M, V, E, PS |
| Rothlind et al., 2015 [47] | 80 | 6 | Yes | ON/ON | None | E, A/C | E, M, A/C, L, PS |
PD: Parkinson's disease; GPi: globus pallidus interna; N: number of patients; mo: months; A/C: attention/concentration; E: executive; GC: global cognition; L: language; M: memory; PS: psychomotor/processing speed; V: visual. Note. Multiple tests were performed for each domain in each study, and often a few of these showed a difference while other tests assessing the same domain did not. This explains why the same domain might appear more than once and under different results for the same study. Adapted from Mehanna [101] with permission from the author.