(PS8-D75) Do Significant Other Reactions to Impulsive Behaviours in Borderline Personality Disorder Predict Future Impulsive Behaviours? An Ecological Momentary Assessment Study

Borderline personality disorder (BPD) theoretically arises from a reciprocal interplay between intrapersonal/emotional (e.g., emotion reactivity) and interpersonal (e.g., conflictual relationships) factors (Linehan, 1993). Recent models of BPD highlight the critical role that relationships play in the development and maintenance of BPD symptoms (e.g., Fitzpatrick et al., 2021). Impulsive, destructive behaviours in BPD (e.g., suicidal behaviours, non-suicidal self-injury, binge eating, substance use, risky sexual activity) represent a core feature of the disorder that may be elicited by interpersonal factors (e.g., conflict, neglect). Indeed, research suggests that that impulsive behaviours in BPD are particularly likely to serve both intrapersonal (e.g., emotion regulation) and interpersonal functions (e.g., peer bonding; Klonsky et al., 2015). Therefore, the way that significant others (SOs) respond to impulsive behaviours in those with BPD may be particularly likely to extinguish or reinforce them. However, no previous studies have actually sought to identify how SOs react to impulsive behaviours in BPD and whether SO negative reactions predict future impulsive behaviours in their loved one with BPD. The purpose of this study is to 1) characterize how SOs react to impulsive behaviours in their loved one with BPD; 2) identify whether negative SO reactions predict future impulsive behaviours in their loved one with BPD; and if so, 3) whether positive SO reactions buffer this relationship.

Forty-six SOs of individuals with BPD were recruited to partake in an ecological momentary assessment (EMA) study whereby participants completed daily assessments on their mobile phone (5x/day for 21 days) assessing how many times their loved one with BPD engaged in impulsive behaviours (e.g., suicidal behaviours, binge eating) and how many times SOs responded with positive reactions (including emotional support and tangible aid) and negative reactions. Results revealed that when SOs reported that their loved one with BPD engaged in impulsive behaviours, they responded with negative reactions 39.82% of the time (e.g., neglected their needs, accused them of seeking attention), emotional support 80.08% of the time (e.g., listened to their thoughts/feelings), and tangible aid 30.78% of the time (e.g., encouraged them to seek counselling). Generalized estimating equations (GEEs) revealed that negative reactions from SOs at one time point (i.e., T1) did not significantly predict impulsive behaviours in their loved one at the subsequent time point (i.e., T2) while controlling for impulsive behaviours at T1, χ² (1) = 2.238, p = .135. When entered into the model, positive SO reactions at T1 also did not significantly predict their loved one’s impulsive behaviours at T2, χ² (1) = .443, p = .506. These results suggest that SO reactions (whether positive or negative) may not influence the likelihood that their loved one with BPD will engage in future impulsive behaviours. Given that impulsive behaviours may not be fully captured by SO informant reports, future research is needed to replicate these findings by directly assessing impulsive behaviours among individuals with BPD and how they are influenced by SO reactions.