Hearing the title of my scheduled talk, “Evidence-Based Treatment of Borderline Personality Disorder (BPD),” colleagues kidded me, saying. “Marcia, that’s an oxymoron—a concept as paradoxical as ‘airplane food’ or ‘postal service.’ ‘Evidence?’ There’s not enough ‘evidence’ on which to base the treatment of BPD.”
This reaction reflects common misperceptions about what constitutes “evidence-based medicine.” Similar misperceptions probably prompted David Sackett, one of the founders of the process, to write the paper “Evidence-Based Medicine: What It Is and What It Isn’t: Its About Integrating Individual Clinical Expertise and the Best External Evidence” (BMJ1996; 312:71-72).
As Sackett stated, evidence-based medicine is not about making decisions based solely on the results of controlled studies. It is not about providing a cookbook approach or clinging rigidly to algorithms or reifying evidence. It is about being clinically and culturally sensitive and evidence informed. Formulate the question, search for answers, appraise the evidence, apply the results, and assess the outcome.
APA’s Practice Guideline Development Process for BPD
The DSM-III publication in 1980 was the first time borderline personality was officially defined. In 1989 APA convened a task force to review the possibility of developing a treatment guideline for patients with borderline personality disorder. The group appreciated that such treatment is very difficult; it is associated with severe transference and countertransference problems and has a highly variable outcome. The questions were there, but there was not enough material in the literature to enable APA to develop a treatment guideline.
The question of a guideline was revisited in 1999, at which time there was a fair-sized database that included some randomized controlled studies. The guideline is not as evidence rich as the treatment guideline for bipolar illness, which cites 492 references, but with 198 references, the BPD guideline is certainly not evidence poor. In the BPD guideline, important references to clinical trials comparing the efficacy of different psychopharmacologic approaches to symptom spectra commonly suffered by these patients are noted. The evidence also includes four published randomized, controlled studies of psychotherapy. These were all long term, and one paper had an 18-month follow-up with impressive positive data.
Explicating Evidence-Based Medicine
To quote Sackett again, “It [evidence-based medicine] is the conscientious, explicit, and judicious use of current best evidence in making decisions about the care of individual patients.” An example in the guideline of this principle is the recommendations regarding the use of MAO inhibitors. Although the efficacy of MAO inhibitors is equal to that of SSRIs for reducing affective dysregulation in patients with BPD, they are not a first-line choice in the treatment algorithm. In the context of informed consent for the use of MAO inhibitors, safety considerations are heightened for patients who are impulsive and suicidally vulnerable. The potentiation of sympathomimetic drugs or related compounds by MAO inhibitors may produce hypertensive crises. High concentrations of tyramine or dopamine in aged cheese, beer, wine, liver, dry sausage, fava beans, and excessive intake of caffeine may also generate hypertensive crises. Impulsive or suicidal patients may forget or purposely ignore these dietary limitations. Treatment with an SSRI avoids this considerable risk.
Evidence-based medicine requires us to evaluate the validity and reliability of the available evidence, but not lose sight of the limitations of this evidence. Common problems are that trials are small, have a short duration, rely on surrogate outcomes, or use controls of uncertain validity. Presented with internally valid, well-conducted trials, sensitive clinicians will still face the need to determine how to apply this evidence to our individual patients.
Psychiatrists practicing evidence based-medicine will identify and apply the most efficacious interventions to maximize the quality of life for their patients. This is not a cost-saving device. Adoption of this clinical strategy may raise rather than lower the cost of patient care.
Is evidence-based treatment of patients suffering from BPD an oxymoron?
The answer is clearly “No.” Unfortunately, we can’t say the same for airline food or postal service. ▪