P1‐228: THE APPLICATION OF THE NIA‐AA ATN SYSTEM TO THE ISTANBUL COHORT. (1st July 2019) - Gurvit, Hakan I.; Yildirim, Zerrin; Bilgiç, Başar; Tufekcioglu, Zeynep; Tatlidede, Asli Demirtas; Ak, Duygu Gezen; Dursun, Erdinc; Hanagasi, Hasmet A.; Emre, Murat