Introduction: Few studies have tested the interaction between handedness and side of onset in Parkinson’s disease. However there is less research on how handedness affects surgical outcomes following DBS. In other CNS disease, most notably stroke, it has long been known that outcomes are worse in left handed patients, likely due to left handers having less lateralization of function. The purpose of this analysis is to determine the relationship between handedness and outcomes following DBS.
Methods: A quality assurance review of the DBS clinical database at one institution was used for analysis. Handedness was measured with the Oldfield Inventory. Primary outcome measures included Dementia Rating Scale (DRS2), Mini-Mental Status Exam (MMSE), Trailmaking Test A and Trailmaking Test B at pre-operative baseline, 3 and 12 months postoperatively. SAS proc GEE was used to test changes over time in a repeated measures analysis.
Results: NCRH patients have lower DR2-total scores (coeff=-1.44, p=0.0289) and MMSE scores (p=0.0293) indicating that left handed patients are more neurocognitively impaired than right-handed patients. The pattern over time is that right handed patients have steady scores over time while for left-handed patients, the scores dropped at 3 and 6 months but improved by 12 months.
Conclusions: Handedness appears to be an independent predictor of outcomes following DBS surgery. Although there is an immediate deficit, they do appear to recover to the same level as right-handers by 12 months post-surgery. If this result bears out in other samples it may suggest a different approach to DBS management in left-handers.
Patient Care: Could change management of left-handed patients.
Learning Objectives: By the conclusion of the session, participants should be able to 1) discuss the measurement of handedness in the PD population 2) understand repeated measures analysis and 3) understand the relationship of handedness to DBS outcomes