Simple versus complex assessment of white matter hyperintensities in relation to physical performance and cognition: The LADIS study

Background: White matter hyperintensities (WMH) on MRI are associated with disorders of gait and balance and with cognitive impairment. The most suitable method to assess WMH in relation to the clinical evaluation of disturbances in these areas has not yet been established. Aim: To compare a simple visual rating scale, a detailed visual rating scale and volumetric assessment of WMH with respect to their associations with clinical measures of physical performance and cognition. Methods: Data were drawn from the multicentre, multinational LADIS study. Data of 574 subjects were available. MRI analysis included assessment of WMH using the simple Fazekas scale, the more complex Scheltens scale and a semi-automated volumetric method. Disturbances of gait and balance and general cognitive function were assessed using the Short Physical Performance Battery (SPPB) and the Mini Mental State Examination (MMSE), respectively. Results: Irrespective of the method of measuring WMH, subjects with disturbances of gait and balance (SPPB≤10) had more WMH than subjects with normal physical performance. Subjects with mild cognitive deficits (MMSE≤25) had more WMH than subjects with normal cognition. Correlations between clinical measures and WMH were equal across methods of WMH measurement (SPPB: Spearman r=-0.22, -0.25, -0.26, all p<0.001; MMSE: Spearman r=-0.11, -0.10, -0.09, all p<0.05, for Fazekas scale, Scheltens scale and volumetry, respectively). These associations remained significant and comparable after correcting for age, gender and education in multivariate linear regression analyses. Conclusion: Simple and complex measures of WMH yield comparable associations with measures of physical performance and cognition. This suggests that a simple visual rating scale may be sufficient, when analyzing relationships between clinical parameters and WMH in a clinical setting.