Yatawara C, et al. - Researchers performed this cross-sectional study of 91 patients with mild Alzheimer's disease (AD) and 79 healthy elderly, who had similar depressive symptoms, WMH volume, cardiovascular risk, age and gender, to examine if, in patients with AD, white matter lesions (WML) mediated the relationship between reduced tract integrity and depressive symptoms, as well as how individual features moderate this effect. The relationship between reduced tract integrity and depressive symptoms in elderly with mild AD was noted to be fully mediated by WML. Right hemispheric cortical-subcortical tracts and the genu of the corpus callosum showed this mediation effect. The effect was strongest in those over 65 years. Depressive symptoms were not correlated to either tracts or WML in matched cognitively healthy controls. This suggests a possible necessity of WML for the pathogenic connection between tract integrity and the manifestation of depressive symptoms in mild AD. Reducing WML thus seems valuable as an important prevention and treatment strategy for depression in mild AD.