Effect of MRI white matter hyperintensities on levodopa response in patients with idiopathic Parkinson´s disease

JULIETA ARENA; DANIEL CERQUETTI; MALCO ROSSI; MARCELO MERELLO

Estocolmo

Congreso; 18th International Congress of Parkinson?s Disease and Movement Disorders; 2014

Objective: Determine whether the presence of white matter hyperintensities (WMH) on magnetic resonance imaging (MRI) influences the acute response to L-dopa in patients with Parkinson?s disease (PD).Methods: We prospectively recruited and evaluated 60 patients with PD using acute Levodopa challenge test, assessing their motor performance with de Movement Disorders Society revised Unified Parkinon?s disease rating scale (MDS-UPDRS) in ?ON? and ?OFF? medication states. The patients? MRIs were evaluated with a visual semiquantitative rating scale to determine the distribution and degree of WMH. The degree of response on the L-dopa challenge test was correlated with the extent and location of white matter damage to determine the possible correlation between them.Results: Participants with overall higher number and extension of WMH showed less response to L-dopa in axial features of the MDS-UPDRS. Moreover, the specific values for deep WMH correlated with the same finding. Neck rigidity showed less response to L-dopa in patients with higher scores in deep and infratentorial WMH.Conclusions: The data presented suggest that WMH may affect L-dopa response in PD patients, possibly through disruption of non-dopaminergic (cortico-basal ganglia) motor pathways, making some symptoms less likely to respond to dopamine replacement. Modification of the risks factors which are associated with increased WMH burden could ameliorate or delay the emergence of later morbidity.