Reports of sex and age differences in the presentation of borderline symptoms have been limited to the Western literature and have not systematically compared adolescents with emerging and older adults with borderline personality disorder (BPD). This study aimed to examine the impact of age and sex on the expression of borderline symptoms in adolescents, young adults, and older adults with BPD. A sample of 493 Iranian individuals with a confirmed diagnosis of BPD was segregated into 2 age groups: 134 young people aged 12-25 (mean = 17.60), and 142 adults aged 26 and older (mean = 31.69). Young people were divided into: 241 adolescents (mean = 15.59) and 100 young adults (mean = 22.45). Older groups compared with their younger counterparts showed significantly greater severity of borderline symptoms and greater difficulties with emotion regulation, but younger groups showed greater emotional and behavioral dysregulation. Sex differences generally mirrored those reported in the Western literature. Despite being limited by its cross-sectional design, this study suggests that adolescents, young adults, and older adults differ significantly in the way their borderline symptoms are expressed. The development of gender identity in adolescents with BPD and a disturbed sense of self is a neglected but potentially fruitful area of future research.
Keywords: adolescence; antisocial; borderline personality disorder; gender; personality disorder; sex differences.
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