White matter hyperintensity burden on magnetic resonance imaging in essential tremor.

BACKGROUND

Whereas structural abnormalities in the cerebellum have been associated with essential tremor (ET), the contribution of vascular disease via white matter hyperintensities (WMHs) and strokes has not been examined. In this study, we have explored these potential associations and hypothesized that ET would be associated with greater overall WMH volume, greater cerebellar WMH volume, and greater infarct presence.

METHODS

In a cross-sectional magnetic resonance imaging (MRI) study of 540 community-dwelling elderly persons in northern Manhattan, New York, brain measures of total WMH volume and regional WMH volume were derived from T(2)-weighted fluid attenuated inverse recovery-weighted MR images. The presence of cerebral infarcts on MRI was determined as well.

RESULTS

Total WMH volume was greater among 33 ET cases than 507 controls in both univariate (OR = 1.41, p = 0.038) and fully adjusted analyses (OR = 1.44, p = 0.03). Cerebellar WMH volume was associated with marginally increased odds of ET in a univariate model (OR = 1.52, p = 0.11) and significantly increased odds in a fully adjusted multivariate model (OR = 1.74, p = 0.049). Temporal lobe WMH volume was associated with significantly increased odds of ET in both univariate (OR = 3.36, p<0.001) and fully adjusted models (OR = 3.73, p<0.001). Large strokes were significantly more common in cases than in controls in unadjusted analyses (OR = 3.04, p = 0.02) and marginally in adjusted analyses (OR = 2.56-2.57, p = 0.045-0.056). The distribution of strokes did not differ by diagnosis.

DISCUSSION: MRI data in this study indicated that ET was associated with greater total WMH volume, greater cerebellar WMH volume and possibly more strokes. Cerebrovascular disease could play a role in the development of ET.