Table 3 Overlapping features between ADHD and BPD

• Childhood or early adolescent onset (note: recent literature highlights early adult onset in some cases) [115]

• Adolescent or early adult onset

• Chronic (trait-like) symptoms and persistent course

• Chronic (trait-like) symptoms and persistence course

• Pattern of unstable interpersonal relationships is a common associated characteristic

• Pattern of unstable interpersonal relationships

• Affective instability is common associated characteristic

• Affective instability

• Risk taking behaviour (behavioural impulsivity) is an associated characteristic

• Behavioural impulsivity/risk taking

• Inappropriate anger or difficulty controlling anger is a common associated characteristic

• Inappropriate anger or difficulty controlling anger