Hippocampal atrophy predicts conversion to dementia after STN-DBS in Parkinson's disease
S Aybek, F Lazeyras, A Gronchi-Perrin… - Parkinsonism & related …, 2009 - Elsevier
Parkinsonism & related disorders, 2009•Elsevier
BACKGROUND: Hippocampal atrophy (HA) is a known predictor of dementia in Alzheimer's
disease. HA has been found in advanced Parkinson's disease (PD), but no predicting value
has been demonstrated yet. The identification of such a predictor in candidates for
subthalamic deep brain stimulation (STN-DBS) would be of value. Our objective was to
compare preoperative hippocampal volumes (HV) between PD patients who subsequently
converted to dementia (PDD) after STN-DBS and those who did not (PDnD). METHODS …
disease. HA has been found in advanced Parkinson's disease (PD), but no predicting value
has been demonstrated yet. The identification of such a predictor in candidates for
subthalamic deep brain stimulation (STN-DBS) would be of value. Our objective was to
compare preoperative hippocampal volumes (HV) between PD patients who subsequently
converted to dementia (PDD) after STN-DBS and those who did not (PDnD). METHODS …
BACKGROUND
Hippocampal atrophy (HA) is a known predictor of dementia in Alzheimer's disease. HA has been found in advanced Parkinson's disease (PD), but no predicting value has been demonstrated yet. The identification of such a predictor in candidates for subthalamic deep brain stimulation (STN-DBS) would be of value. Our objective was to compare preoperative hippocampal volumes (HV) between PD patients who subsequently converted to dementia (PDD) after STN-DBS and those who did not (PDnD).
METHODS
From a cohort of 70 consecutive STN-DBS treated PD patients, 14 converted to dementia over 25.6±20.2months (PDD). They were compared to 14 matched controls (PDnD) who did not convert to dementia after 43.9±11.7months. On the preoperative 3D MPRAGE MRI images, HV and total brain volumes (TBV) were measured by a blinded investigator using manual and automatic segmentation respectively.
RESULTS
PDD had smaller preoperative HV than PDnD (1.95±0.29ml; 2.28±0.33ml; p<0.01). This difference reinforced after normalization for TBV (3.28±0.48, 3.93±0.60; p<0.01). Every 0.1ml decrease of HV increased the likelihood to develop dementia by 24.6%. A large overlap was found between PD and PDnD HVs, precluding the identification of a cut-off score.
CONCLUSIONS
As in Alzheimer's disease, HA may be a predictor of the conversion to dementia in PD. This preoperative predictor suggests that the development of dementia after STN-DBS is related to the disease progression, rather then the procedure. Further studies are needed to define a cut-off score for HA, in order to affine its predictive value for an individual patient.
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