Consistency and coherence in treatment outcome measures for borderline personality disorder

Recent meta-analyses and reviews highlight the variety of outcomes utilized to operationalize
short-term outcomes. Similar to the heterogeneity in the diagnostic phenomenology
of BPD, there, too, is significant heterogeneity in outcomes – both in terms of domains
measured and in methods of measurement (e.g., self-report vs. interview). In their
review of psychotherapy trials, Stoffers and colleagues 1] dichotomized outcomes as primary and secondary. Primary outcomes included: overall
BPD severity and BPD symptom severity (i.e., anger, affective instability, chronic
feelings of emptiness, impulsivity, suicidality, parasuicidality/self-harm, general
interpersonal problems, avoidance of abandonment, identity disturbance, and dissociative/paranoid
ideation). Secondary outcomes included: psychiatric comorbidity, general distress,
global assessment of functioning, attrition/noncompliance with treatment, and adverse
events. Additional outcomes included (in some studies) measurement of hospitalizations
and emergency department visits. Note, however, that no study assessed all domains,
and there was little overlap in measures used among the studies. Lieb et al.’s 2] review of pharmacotherapy trials included all of the aforementioned outcomes but
also included medication tolerability and side-effects. There was a similar pattern
of multiple domains assessed and multiple methods of measurement with little overlap
across studies. Noting the lack of coherence and consistency across RCTs for BPD,
Lieb and colleagues 2] as well as Zanarini and colleagues 6] both have called for a coherent set of measures to aid in systematic evaluation of
treatment models and best practices.

Longer-term follow-up studies (e.g., 7]-9]) suggest that many patients with BPD do well over time with most no longer meeting
the required threshold number of diagnostic criteria; however, remission from a diagnosis
and recovery from an illness are not comparable outcomes. With treatment and over
time, some symptoms resolve (e.g., impulsivity) more readily than others (e.g., chronic
dysphoria), but many individuals continue to have difficulties that require treatment
8],10],11]. These individuals will likely qualify for diagnosis of personality disorder, trait
specified within the new DSM-5 system. Remission from a BPD diagnosis is a desired
outcome but likely not the ultimate end point. The McLean Study of Adult Development
and its extensions 9] define recovery as a constellation of symptomatic remission, good social and vocational
functioning, and stability of the aggregate over an extended period of years. Recovery
from BPD appears to be among the most stringent outcomes in the current literature;
few treatment trials are likely to achieve this decades-long end point. Outside of
formal research settings, assessment of recovery is rarely considered, much less done.