Affective instability – repeated, rapid, and abrupt shifts in mood – should be used as a ‘gate criterion’ for borderline personality disorder (BPD), and could address the historic under-recognition of the disorder, a paper has proposed.

The paper, published in The British Journal of Psychiatry, recommends that the presence of affective instability in patients be used to screen for BPD. The paper notes that while there are currently ‘gate’ criteria in place for conditions such as generalised anxiety disorder, substance abuse disorder and panic disorder, there is no such system for detecting BPD.

The paper concludes that if a patient has a lot of sudden changes in mood, this will identify BPD in the vast majority of cases. Conversely, if a patient does not experience this problem, they are unlikely to have BPD.

Borderline personality disorder is a serious mental health condition resulting in high levels of emotional distress, reduced health-related quality of life, high use of services and excess mortality. The under-recognition of BPD has been identified as a significant clinical problem. It is hoped, therefore, that these findings will result in the improved efficacy of diagnosis when screening for BPD. 

Dr Mike Crawford from the Royal College of Psychiatrists said: “It takes time to get to understand a person’s personality. But the results of this study suggest that asking people about sudden changes in mood is a good starting point for assessing whether they may have borderline personality disorder. This is important to help ensure that people receive effective treatment and avoid treatments that do not work.”