Table 1.
The Effect of Levodopa and DBS in Advanced PD.
| Symptom | Effect of levodopa | Effect of DBS |
|---|---|---|
| Rigidity | Improves | Improves |
| Bradykinesia | Improves | Improves |
| Tremor | Improves | Improves |
| Gait/Balance | Individual components of gait and balance appear to respond uniquely | Evidence supports better results with GPi DBS |
| Dyskinesia | May worsen | Improves |
| Off time | Medicine adjustments may not improve off time in advanced PD | Improves |
| Cognitive Function | May worsen during off times | Studies have demonstrated worsened verbal fluency and set shifting abilities during complex tasks following STN DBS |
| Mood and apathy | May improve | May worsen with STN DBS, especially with rapid medication reduction and in patients with history of ICD |
| Speech | No change | May worsen, especially with bilateral STN DBS |
| Quality of life | Improves | Improves |
Key: PD, Parkinson's disease; DBS, deep brain stimulation; STN, subthalamic nucleus; GPi, internal segment of the globus pallidus; ICD, impulse control disorders.