مفروضات در اختلال شخصیت مرزی: ویژگی، ثبات و ارتباط با عوامل اتیولوژیک

The specificity and stability of a set of assumptions hypothesized to be characteristic of Borderline Personality Disorder (BPD) was investigated. BPD patients (n=16) were compared to cluster-C personality disorder patients (n=12) and to normal controls (n=15). All subjects were female and diagnosed with SCID-I and -II. Subjects rated a short version of the Personality Disorder Beliefs Questionnaire (PDBQ), with six sets of 20 assumptions each, hypothesized to be characteristic of avoidant, dependent, obsessive-compulsive, paranoid, histrionic and borderline personality disorder. The BPD assumptions (Cronbach alpha=0.95) proved to be the most specific to BPD patients. Subjects rated the shortened PDBQ again after viewing an emotional video fragment one week later. Despite increased negative emotions, the PDBQ ratings remained relatively stable. Confirming the cognitive hypothesis, regression analyses indicated that the BPD assumptions mediate the relationship between self-reported etiological factors from childhood (sexual abuse and emotional/physical abuse) and BPD pathology assessed with the SCID-II. It is suggested that a set of assumptions is characteristic of BPD, and is relatively stable despite the instability of the behaviour of people diagnosed as having BPD.

In cognitive views of personality disorders a central role is given to schemas, generalized representations of the self, others, and the world, of the relationships between these elements, and of the main strategies for survival (Beck et al., 1990; Young, 1990). These schemas are hypothesized to result from the interaction between dispositional and environmental factors during childhood and, once formed, to strongly influence informational input by selective and interpretative processes. Though the content of these schemas are hypothesized to be mainly constituted by tacit knowledge, therefore unaccessible for direct introspection, it is believed in cognitive views that important aspects of schemas can be represented in so-called assumptions, verbal circumscriptions of fundamental beliefs, like ``I'm inherently bad'' and ``If you do not dominate the other person, he/she will dominate you''. By letting Ss rate the degree they believe in these propositions it is hypothesized that the content of their schemas becomes measurable. Various suggestions have been made about the assumptions that are central in personality disorders: Beck et al. (1990) offer an extensive list of assumptions for most DSM-III-R personality disorders; Young (1990) has offered a somewhat different view by suggesting that 18 themes like self-sacrifice and entitlement are fundamental dimensions in personality pathology (see Schmidt, Joiner, Young, & Telch, 1995, for a psychometric evaluation of Young's Schema Questionnaire). Despite the fact that the Borderline Personality Disorder (BPD) is one of the most severe and common disorders in psychiatry, almost nothing is known about the assumptions that may be central in this disorder. Beck et al. (1990), for instance, do not give a list of assumptions characteristic of BPD, stating that BPD is an exception among the personality disorders by not being characterized by a specific set of beliefs. Young (see Beck et al. (1990), p. 185) has suggested that nine of his `early maladaptive schemas' are playing a role in BPD, but the number is quite large to consider this as the essence of the core beliefs in BPD. Despite the omission of a list of BPD assumptions in the Beck et al. (1990) book, the chapter on BPD makes some specific suggestions: BPD individuals are believed to view themselves as inherently bad, powerless and vulnerable, and to view the world (we would say others) as dangerous and malignant. Arntz (1994) has elaborated on this suggestion by hypothesizing that these fundamental beliefs are related to childhood etiological factors common in BPD: sexual abuse by intimates in particular, but also emotional and physical abuse and neglect ( Bryer, Nelson, Miller, & Krol, 1987; Stone, Unwin, Beacham, & Swenson, 1988; Coons, Bowman, Pellow, & Schneider, 1989; Herman, Perry, & van der Kolk, 1989; Ogata, Silk, Goodrich, Lohr, Westen, & Hil, 1990; Weaver & Clum, 1993). In short, it is hypothesized that if members of the nuclear family (or its substitute) in which the child grows up (sexually/physically/emotionally) abuse the child, especially in the 6–12 yr range, the formation of the idea to be inherently bad, that nobody can be trusted and that others will abuse, punish or leave you when you become intimate and dependent, are fostered. It has also been hypothesized that BPD is characterized by a cognitive-emotional developmental stagnation on areas related to these issues, resulting, for instance, in dichotomous thinking (see Veen & Arntz, 1997, for a test of the schema-specificity of dichotomous thinking in BPD). The first aim of the present study was to test whether a set of assumptions (hereafter to be referred to as BPD assumptions) derived from the work by Beck et al. (1990) and Arntz (1994) is characteristic of BPD. To test this issue a 3-group design was chosen: a group of BPD patients was compared with a psychiatric control group and a healthy control group. The DSM-III-R (and DSM-IV) distinguishes three clusters of PDs: the `odd' cluster-A (paranoid, schizoid, and schizotypal PDs); the `dramatic' cluster-B (histrionic, narcissistic, borderline, and anti-social PDs); and the `anxious' cluster-C (avoidant, dependent, obsessive-compulsive, and passive-aggressive PDs). Since there is considerable comorbidity between BPD and cluster-A PDs and other cluster-B PDs, it was decided in this stage of research to compare BPD with cluster-C PDs. In this way clearly distinguishable groups could be compared. As a first test of the specificity hypothesis the present study compared BPD patients with cluster-C patients and normals, with respect to assumptions hypothesized to be specific to BPD as well as with respect to five groups of assumptions hypothesized to be specific to other PDs (avoidant, dependent, obsessive-compulsive, paranoid and histrionic). To avoid possible sex influences and because of the high proportion of women in BPD populations in psychiatric settings, only women were studied. Given the high level of pathology and the high number of comorbidity of personality disorders in BPD patients it was expected that BPD patients would believe to a degree comparable to cluster-C patients in cluster-C beliefs, but would surpass these patients as to cluster-A and -B beliefs. It was specifically expected that the group of assumptions hypothesized to be characteristic of BPD would discriminate BPD patients most clearly from the other groups. The second aim was to test the stability of the beliefs. BPD is said to be a disorder characterized by strong fluctuations, and it can therefore be doubted whether BPD assumptions are stable. Perhaps the belief in various assumptions is as fluctuating as the mood and the behaviour of these patients. Instead of waiting for spontaneous fluctuations, an attempt was made to induce a negative emotional state and to prime BPD characteristic schemas (Safran, Segal, Hill, & Whiffen, 1990) by letting the Ss view an emotional video fragment foregoing the second test. Belief ratings of the second test were compaired with those of the first test. Lastly, it was attempted to test whether the relationship between retrospective reports of childhood traumas and BPD assumptions support the hypothesis that these assumptions may originate from childhood traumas. More specifically, it was tested whether the relationship between trauma reports (in particular sexual abuse) and BPD as assessed with a semi structured interview (SCID-II) was mediated by these assumptions.