According to the article dated June 28, 1242, of "Azuma Kagami", he became hyojoshu (a member of Council of State) at the age of 30, and according to the article dated December 21, 1253, 'the former Kai no kami (the governor of Kai Province) Shogoinoge (Senior Fifth Rank, Lower Grade) Oe Ason (second highest of the eight hereditary titles) Yasuhide passed away (at the age of 42).
そして『吾妻鏡』1242年（仁治3年）6月28日条によれば、30歳で評定衆となり、そして同1253年（建長5年）12月21日条には単独で「前甲斐守正五位下大江朝臣泰秀卒す（年四十二）」とある。