Abstract Background Borderline personality disorder (BPD) is a significant cause of morbidity with no approved pharmacological treatment. We assessed treatment trajectories of patients with BPD in real-world clinical practice to help identify treatment gaps. Methods This retrospective, observational, cohort study used de-identified MindLinc electronic health records data from the Holmusk NeuroBlu database (Version 21R2) to analyse the treatment journey of patients with BPD (aged ≥ 12 years with ≥1 diagnosis of BPD) that were prescribed pharmacological treatment within 14 days of diagnosis (baseline) and had treatment data for ≥12 months. Results Of those prescribed pharmacological treatment at baseline, 1461 patients (16.1%) had 12 months of follow-up data. Antidepressants were the most frequently prescribed medication at baseline (80.4%) either alone or in combination with other medication classes, followed by second-generation antipsychotics (SGAs), anxiolytics and mood stabilisers. In the 12 months post-baseline, the most frequently recorded treatment pathway was a switch from 1 antidepressant to another. Sertraline (5.5%), fluoxetine (5%), and citalopram (5%) were the most-prescribed antidepressants; lamotrigine (24.9%), gabapentin (15.4%), and valproate (7.1%) were the most prescribed mood stabilisers; and quetiapine (22.1%) and aripiprazole (19.0%) were the most prescribed SGAs. Polypharmacy (defined as the prescription of ≥ 1 psychotropic medication) was observed in 83.1% of patients at baseline and increased with follow-up time and age. Conclusion The high rates of polypharmacy observed suggest that current clinical practices may not fully align with treatment guidelines for BPD, and that patients with BPD experience a considerable treatment burden. Limitations of this study include the absence of psychotherapy data and the use of prescription records without information on treatment adherence. Nonetheless, the diversity of treatment patterns observed reflects the complex symptomatology of BPD and highlights the need to deepen our understanding of its neurobiology to improve pharmacological treatment strategies and translate to meaningful patient outcomes. Clinical trial number Not applicable
White et al. (Fri,) studied this question.