“…Several studies have reported that WMH volume is increased in patients with diabetes compared with non-diabetic subjects ( Novak et al, 2006 ; Raffield et al, 2016 ); however, other studies did not observe this finding ( Falvey et al, 2013 ; Moran et al, 2013 ). Some studies have focused on the association between HbA1c or fasting plasma glucose levels and WMH; however, the results of these studies were inconsistent ( Bryan et al, 2014 ; Exalto et al, 2014 ; Geijselaers et al, 2015 ; Raffield et al, 2016 ; Schneider et al, 2017 ). More recently, an association between fluctuations in HbA1c levels and WMH was reported in diabetes patients who carry the apolipoprotein E4 allele ( Livny et al, 2016 ), which is a strong genetic risk factor for AD.…”