“…The no-DH group might have included patients with undetected DHs, considering the short duration of DH [ 39 ]. However, the interval of three months for DH observation in this study is comparable to that adopted in other studies on DHs [ 11 , 14 , 15 , 16 , 17 , 18 , 20 , 22 , 24 , 29 , 32 , 33 , 34 , 36 , 37 , 38 ]. Although we did not examine the association between DH and systemic diseases or drug usage, systemic hypertension [ 19 , 21 ], diabetes [ 19 , 45 ] and use of aspirin [ 45 ] were reported to be significantly associated with DH occurrence.…”