White matter hyperintensities (WMH) have been shown to progress over time but they might regress too. Little is known about the regression of WMH as the main focus has been on progression. We investigate WMH regression and their dynamic properties using diffusion MRI. Areas of WMH change, both progression and regression, might have different tissue integrity properties than areas that are more stable, i.e. stable normal-appearing white matter (NAWM), become more hyperintense, or stable WMH. Mean diffusivity and peak width of skeletonized mean diffusivity (PSMD) might be most sensitive to subtle integrity changes before they become visible on structural MRI.