Correlation between Taijin-Kyofu-sho and Attention Deficit Hyperactivity Disorder among University Students: A Self-Reported Assessment Study

Taijin-Kyofu-sho (TK) is regarded as a culture-bound anxiety disorder in East Asian counties. Despite its earlier discovery in Japan, fewer studies have focused on TK than on social anxiety disorder (SAD) and even fewer on TK comorbidity with developmental disorders. Thus, we examined the association between TK and attention deficit hyperactivity disorder (ADHD) among Japanese university students. A total of 673 students (500 male, 173 female) were assessed on the Japanese version of Liebowitz Social Anxiety Scale (LSAS-J), TK scale, and adult ADHD Self-Report Scale (ASRS; version 1.1). On the TK scale and LSAS-J, 17.4 and 10.3 percent of students, respectively, exceeded the cut-off value. Furthermore, ASRS scores more strongly correlated with TK scale than LSAS-J scores (TK scale: r = 0.427; LSAS-J: r = 0.330). To evaluate how TK or SAD with ADHD affects those scores, we divided subjects into four groups: healthy subjects, subjects with TK, those with SAD, and those with both disorders. The total ASRS score was significantly higher in TK-only subjects than in healthy subjects (p < 0.0001). However, there was no significant difference between scores of healthy and SAD-only subjects (p = 0.281). Our results indicate a possible link between ADHD and later development of TK in Japan.