This is the first and only study to date that investigated the application of psychotherapy for Chinese suicidal patients with borderline personality disorder in a Mandarin speaking society. We compared treatment efficacies of DBT and therapies from experts professionally trained in suicide prevention. Although reductions in non-suicidal self- injurious behaviors, outpatient and emergency visits due to suicidal ideation or attempts, suicidal ideations, psychological, or psychiatric symptoms of borderline personality disorder were found in both groups over the one-year treatment period, no significant group*time effects on study outcomes were found in comparing the DBT and the CTBE groups. Our results indicate that effects of Mandarin-translated DBT delivered in Taiwan were similar to therapies carried out by experts in suicide prevention.
Our results of pre-post reductions in self-harm behaviors, borderline symptoms, and general distress in the DBT group are similar with previous studies (12, 13, 17, 31). As discussed in other studies, the effectiveness of DBT may be due to encouragements to practice and the generalization effect of DBT skills to the environment outside the therapy room. DBT therapists also validate that dysfunctional behaviors ‘make sense’ in the context of patients’ life experiences without approving such behaviors in order to make behavior change happen (35).
However, our finding that DBT and CTBE had no between-group differences across a broad range of outcomes is contrary to our prediction and Linehan et. al’s result, in which DBT was superior to community experts in preventing suicide attempts (13). The present study differs from Linehan et. al in that community experts in the Linehan et. al study had not received specific training in suicide prevention. Our results were more comparable with McMain et. al’s results demonstrating DBT and CTBE as equally effective when delivering DBT in a publicly funded health care system in Canada.
Although our findings further demonstrate that self-harm behaviors and psychiatric distress related to borderline symptoms may be improved under both treatment modalities, we cannot say with certainty that there were determining differences in both treatments. The DBT group participants need to attend more group and individual sessions, had lower BSSI at baseline, or higher dropout rates, and may affect the results that showed improvements in suicidal ideation and quality of life occurred in the CTBE condition only. The finding that more DBT participants described of validation, emotions identification, and extra time from therapists, as captured by the THI at the 4-month timepoint, may reflect the major components (i.e. validation and acceptance, balanced with cognitive and emotional change; along with telephone consultation) of DBT that are different from the comparator. In the absence of session recordings from the comparison treatment, it is not possible to review session content to determine presence or absence of specific DBT strategies that may account for treatment outcome. As abundant strategies and skills are contained within DBT, patient’s perception of treatment elements delivered are worthy of further investigation to demonstrate what might bring out therapeutic effects from the treatment.
Beside the factor that community experts in this study were professionals trained in suicide prevention, other reasons might also be responsible for the lack of significant between-group differences. First, agreeing with recommendations from the APA practice guidelines, we believe the role of attending psychiatrists, including follow-up care and contacts, or psychotropic agents such as lithium, might be helpful in the management of suicidal patients (17). However, since psychotherapy is supported by evidence as the frontline treatment for personality disorders (5, 6), the provision of only general psychiatric management for Chinese patients with borderline personality disorder in Taiwan may still be premature and needs further research. Second, as psychiatric management in our study was not directed or controlled by the research team, psychiatrists providing care in this study included those with and without DBT training. More than half of the psychiatrists providing general psychiatric care to patients in the CTBE group had reported having received DBT training or describe themselves as DBT therapists. Although we specifically requested that psychiatrists provide only general psychiatric pharmacotherapy or management, it might be possible that DBT elements may have been delivered during the course of care. Third, in this real-world study, case management phone consultation by the Suicide Prevention Center associated with the research team’s teaching hospital was also provided to both groups due to regulatory requirements of the hospital. As the Suicide Prevention Center is supervised and staffed by therapists with DBT training, the case management services participants received in both the DBT and CTBE groups was likely infused with DBT elements. Hence, the degree of distinction between DBT and the treatment delivered in the CTBE group should be taken into consideration.
Furthermore, this is also the first study that provides empirical evidence regarding the efficacy of general psychiatric management and psychotherapy provided by community experts for suicidal patients with borderline personality disorder. Taiwan has a National Health Insurance (NHI) system that pays for all medical utilizations. Enrollees only need to pay monthly premiums and a low out-of-pocket fee when receiving health services. However, availability of the NHI-reimbursed psychotherapy or counseling is limited thus requiring a 3 to 6 month wait. Our study showed that a combination of publicly fund psychiatric management and self-paid psychotherapy may be as helpful as the combination with DBT in reducing self-harm behaviors.
Finally, there might still be cultural factors that accounted for having no between- group differences in our study. We found a very high drop- out rate (61%) in the DBT group (compared to an average of 25% from past studies(34), and that participants received DBT often dropped out within the 4-months period after the initiation of individual therapy. It is also possible that we did not have sufficient power to detect the differences between the two groups. From clinical observation, Chinese patients tended to have negative views about group therapy. The reason why our patients disliked group therapy may be associated with the discouragements of individualism in traditional Chinese culture (36). Under the influence of traditional thoughts, modesty and prudence are more honored than expressing personal opinions(37, 38). Therefore, it may require some efforts for Chinese patients to adapt to DBT group therapy in which a patient was expected to share their experiences of practicing and learning DBT skills in front of other group members. In addition, the concept of identifying and regulating emotions is rarely mentioned in the Chinese culture. Expressions of emotions are viewed negatively and as being ‘too emotional’ and are therefore readily repressed. This might also be one of the factors why the therapeutic effect of DBT was not as robust as in the Western culture. Future comparisons from more cross-cultural studies are thus still warranted.
Major strengths of this study include its prospective randomized control design, and the comprehensive measurements administered by trained assessors who were blind to treatment assignment. The word-by-word translation of the DBT skills manual and DBT strategies into Mandarin, as well as the step-by-step implementation of the Western-originated DBT into this Chinese society were also important highlights. Both treatment modalities were delivered by experienced clinicians with expertise in managing suicidal patients. Key limitations were: First, although the CTBE group carried out therapies that comply with the APA guideline, the specific nature of what was delivered lacks rigorous examinations. Second, similar to other studies(17), our study subjects were predominantly female. Whether any modification or enhancements on treatment effects for male BPD cases remains to be investigated. Third, the information of self-harm or suicide episodes were obtained from interview. There might be recall bias from the responder. Besides, the high assessment burden might compromise the validity of the measures. Fourth, the sample size of our study participants was quite small with 30 individuals receiving each treatment. Although we might lack the sufficient power to detect differences between DBT and the active comparator, our Post-hoc analysis also showed that a larger sample would not change the trends toward the differences. Fifth, although more participants from DBT group described the advantage that their therapists took phone calls than from the CTBE group, compared to standard DBT, our DBT therapists only provide phone coaching during working hours instead of taking 24-hour calls. Whether the consultation meeting of the DBT team played the role of group supervision effectively was also unable to verified. These may perhaps be other reasons affecting the efficacy and remain to be explored in further research.