Associations of sleep parameters with psychopathology and treatment success in patients with borderline personality disorder after dialectical behavior therapy

Abstract Background Patients with borderline personality disorder (BPD) often suffer from sleep problems, which interact with BPD-specific symptoms and influence prognosis. The present study investigated the relationships between BPD symptoms, the outcome of dialectical behavior therapy (DBT), and sleep quality and sleep architecture as assessed by polysomnography. Materials and methods Seventeen patients diagnosed with BPD participated in an 8‑week semi-residential DBT program. At the beginning of the program, two nights of polysomnography were conducted in the sleep laboratory. Depressive symptoms, BPD-specific symptoms, and subjective sleep quality were assessed via questionnaires at the beginning and end of the treatment program as well as after 6 months. Results The DBT program successfully decreased depressive and BPD-specific symptoms and increased subjective sleep quality. Patients with the strongest symptoms benefitted more from the treatment. Stronger BPD-specific symptoms were associated with less rapid eye movement (REM) sleep. At the 6‑month follow-up, only depression was still reduced, while BPD-specific symptoms and sleep quality had again worsened. Better subjective sleep quality was associated with a stronger reduction in BSL scores at 6‑month follow-up. Conclusion The DBT program was initially effective. The positive outcome was, however, not permanent, stressing the importance of subsequent disorder-specific outpatient programs. Furthermore, REM sleep might to some extent protect against emotional distress in BDP, and subjective sleep quality was positively correlated with follow-up treatment outcome.