To this end,increased load of enlarged perivascular spaces have been found in Alzheimer’sdisease and mixed dementia compared to cognitively normal subjects, and enlargedperivascular space burden is also associated with tau and amyloid-B pathology.36 Sleep deprivation increases interstitial space fluid and CSF tau as well astau pathology spreading,11 while tau aggregation may have a role in the bidirectional relationshipbetween sleep and Alzheimer’s disease.37 This evidence concerns the gene MAPT and Alzheimer disease.