A profile analysis of personality disorders: Beyond multiple diagnoses

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1 Psychiatry and Clinical Neurosciences (1999), 53, Regular Article A profile analysis of personality disorders: Beyond multiple diagnoses KAZUHISA NAKAO, md, JYO TAKAISHI, md, KENJI TATSUTA, md, HISANORI KATAYAMA, md, MADOKA IWASE, md, KAZUHIRO YORIFUJI, md, KAZUHIRO SHINOSAKI, md AND MASATOSHI TAKEDA, md Department of Psychiatry, Osaka University Medical School, Osaka, Japan Abstract Key words The authors applied cluster analysis and multidimensional scaling to the analyses of 59 patients with personality pathology. Cluster analysis yielded eight typologies of patients: detached, anankastic, phobic, dramatic, erratic, emotional, milder emotional, and masochistic negativistic. Multidimensional scaling identified the dimensions of classifying patients: anxious rumination versus behavioural acting out, overall severity of personality pathology, and assertiveness versus withdrawal. Considering the distinction between personality disorder (dysfunctional personality) and abnormal personality (extreme personality), the following changes in current classification system are proposed: use of a hierarchy and exclusion criteria in a categorical-type model or use of a personality profile in a dimensional-trait model, in either case, with a dimensional rating for severity of psychopathology to define personality disorder. cluster analysis, diagnosis, personality, personality disorders, multidimensional scaling. INTRODUCTION One of the problems in diagnosing personality disorder is multiple diagnoses. Many studies have reported considerable overlap among personality disorder diagnoses. 1 8 However, the meaning of the overlap is unclear since a conclusion has not been reached as to how many distinct personality disorders exist. 5,9 Some personality disorders may be better understood as mere traits such as pride, 10 oral, obsessive, and hysterical personality patterns, 11 dependence and narcissism, 12 which may or may not accompany other personality or psychiatric disorders. Some personality disorders may be of a severe form, 9,13 or a different manifestation, 14 of other personality or psychiatric disorders; in these cases, the division is artificial though clinically useful. 15 Correspondence address: Kazuhisa Nakao, MD, Department of Psychiatry, Osaka University Medical School, 2-2 Yamadaoka, Suita, Osaka 565, Japan. <nakao@psy.med.osaka-u.ac.jp> Received 21 July 1998; revised 5 November 1998; accepted 8 November Even if all personality disorders are conceptualized as distinct, determining the appropriate threshold of severity to mark disorder will greatly affect the perceived degree of comorbidity through probable and possible cases. Also, cross-sectional assessment without longitudinal and historical perspective produces overdiagnosis and inflates base rates due to susceptibility to state phenomena such as Axis I conditions, stress, role, and situation Moreover, multiple diagnoses will be interpreted differently in accord with one s conceptual model for personology. While a dimensional model may regard overlap as natural even in usual cases, 16 19,23,24 a categorical model might see it as exceptional only in severe cases, whether using hierarchy or not, a typological model would find overlap inevitable in boundary cases, regardless of severity Although the models are so diverse, research efforts have been concentrating on classifying items or traits, corresponding to the DSM-III-R 35 statement of classifying psychiatric disorders, not patients. However, do patients, to begin with, have several personality disorders when personality represents something total and unified? In this study, we have tried to classify patients (as opposed to disorders) using a cluster analytic frame-

2 374 K. Nakao et al. work, an approach similar to that which Jaspers recommended for the study of psychopathology 36 and which has been employed for the classification of depression We used the profile of personality disorders to yield a typology of patients using the DSM-III-R Axis II dimensional rating, which is the method suggested by Frances. 23 With cluster analysis, patients are grouped together according to their personality profile. With multidimensional scaling (MDS), the constellation of patient groups is seen in a multidimensional space. Specific questions investigated in this study are: (i) What grouping of patients with personality pathology does cluster analysis yield? and (ii) What dimensional structures emerge in classifying patients? METHOD The study was conducted at the out-patient clinic in Osaka. Diagnoses were made with DSM-III-R and the Japanese diagnostic system, using all available data including a social worker s interview, information from referring clinicians, report of the developmental and life history from the patient and the patient s parents, and if possible, an interview with the patient s family, relatives, and co-workers. In addition, subjects were directly questioned about each DSM-III-R item. In the assessment of the Axis II criteria, longitudinal perspective was emphasized, concentrating on enduring and inflexible patterns, and excluding Axis I effect, role, situational and stress reaction Each criterion was rated as: 2 (definite: present and clinically significant); 1 (present); or 0 (absent). Only a rating of 2 was regarded as indicating that a criterion was fulfilled, and only these fulfilled features were totalled to determine whether a patient met the cut-offs of DSM-III-R personality disorders. The total items refers to the total number of Axis II criteria met altogether. Current functional impairment was assessed with the Global Assessment of Functioning (GAF) scale. Subjects were selected from 299 consecutive cases interviewed by one of the authors (KN). From the initial 299 cases, patients were excluded if they were under 18 years of age (n = 60), could not provide adequate information (e.g. only family members were interviewed) (n = 56), or had diagnoses of schizophrenia and delusional disorder (n = 26), organic mental disorders including epilepsy (n = 6), or alcohol dependence (n = 2). This left 149 patients. From these cases, patients with total items of four or more were chosen for data analyses (n = 59, 34 females and 25 males, mean age of 29 ± 10 years). A sample based on four or more items was determined because four is sufficient to make some personality disorder diagnoses. The sample consisted of 37 patients with any personality disorder and 22 trait cases (less severe cases or cases with mixed personality disorder in DSM-III s term). An analysis was based on the number of Axis II criteria met in each personality disorder. Cluster analysis and MDS was performed with programs of multivariate analysis 71 A hierarchical method (Ward s method) was used for a cluster analysis. RESULTS Cluster analysis Cluster analysis was performed, and eight groups (groups 1 8) were established with a scree method (the distance index was 1.22 for 10, 1.39 for nine, 1.51 for eight, 1.87 for seven, and 2.25 for six groups). Table 1 shows the demographic data GAF, total items, and Axis I diagnoses of groups 1 8. Figure 1 shows the personality profile of these groups. Group 1 Group 1 consisted of three male patients, and the profile showed high on schizoid, schizotypal and avoidant personalities with a slight elevation of paranoid personality. Two individuals had generalized social phobia, a severe form of Taijinkyofu in the Japanese diagnostic system. 42 Group 1 had the lowest GAF among the eight groups. We considered this group detached (schizoid schizotypal avoidant paranoid). Group 2 Group 2 included eight patients (three female and five male), five were trait cases. Its profile showed high on obsessive compulsive personality and a slight elevation of avoidant personality. There were various Axis I diagnoses. This group was considered anankastic (obsessive compulsive). Group 3 Group 3 consisted of 15 patients (nine female and six male), and its profile was high on avoidant and dependent personalities. Ten patients had generalized social phobia and 11 had dysthymia. Four of the 11 dysthymic patients also met the criteria for major depression, i.e. double depression. This group was considered phobic (avoidant dependent).

3 A profile analysis of personality disorders 375 Table 1. Demographic data and Axis I diagnoses Milder Masochistic Group Detached Anankastic Phobic Dramatic Erratic Emotional emotional negativistic n Trait cases (%) % Female Age (years) M (SD) 25 (3) 29 (7) 32 (12) 37 (11) 28 (10) 24 (7) 24 (5) 42 (2) GAF score M (SD) 37 (2) 55 (9) 51 (6) 65 (7) 44 (7) 45 (6) 52 (7) 41 (1) Total items M (SD) 19 (2) 6 (2) 8 (4) 8 (1) 14 (7) 12 (4) 9 (6) 7 (1) Axis I diagnoses Bipolar and cyclothymia 1 1 Major depression Dysthymia GAD 2 1 Panic disorder OCD Social phobia 1 1 GSP Hypochondriasis 1 Dissociative disorder, NOS 2 Alcohol abuse 1 2 Primary insomnia 1 1 GAF, Global Assessment of Functioning; GAD, Generalized Anxiety Disorder; OCD, Obsessive Compulsive Disorder; GSP, Generalized Social Phobia; NOS, not otherwise specified. Group 4 Group 4 consisted of three patients (two female and one male), and its profile showed high narcissistic and histrionic personalities. This group had a higher GAF than any other, and was considered dramatic (narcissistic histrionic). Group 5 Group 5 consisted of 11 patients (six female and five male), whose profile was high on borderline, paranoid and narcissistic personalities, with a slight elevation of schizotypal and histrionic personalities. There were various Axis I diagnoses in this group. This group was considered erratic (borderline paranoid narcissistic). Group 6 Group 6 consisted of seven patients (all female), and its profile showed high on borderline, avoidant, dependent, and self-defeating personalities. Five patients had dysthymia; two patients met the criteria for major depression but none met the criteria for melancholia. These patients belong to Type III (conflict reaction type) in the Kasahara-Kimura classification of depression. 43 Three patients had generalized social phobia and two had alcohol abuse. This group was considered emotional (borderline avoidant dependent self-defeating). Group 7 Group 7 consisted of nine patients (seven female and two male); seven patients were trait cases. Group 5 profile was high on borderline, histrionic, and dependent personalities with a slight elevation of passive aggressive personality. Four patients had major depression; two of these had dysthymia. We considered this group milder emotional (borderline histrionic dependent). Group 8 Group 8 consisted of three male patients and had a profile of high passive aggressive personality with a slight elevation of self-defeating personality. This group was considered masochistic negativistic (passive aggressive). Multidimensional scaling Table 2 shows the configuration of eight groups with 59 patients in three dimensions. The threedimensional representations were chosen to compare our results with those of Widiger et al. 32 Because we used 59 patients, not eight groups, as variables, our

4 376 K. Nakao et al. Figure 1. Profiles of personality disorders in eight groups. (a) group 1 (detached); (b) group 2 (anankastic); (c) group 3 (phobic); (d) group 4 (dramatic); (e) group 5 (erratic); (f) group 6 (emotional); (g) group 7 (milder emotional); and (h) group 8 (masochistic negativistic). PD, personality disorder; PPD, paranoid; SPD, schizoid PD; STPD, schizotypal PD; DPD, dependent PD; OCPD, obsessive compulsive PD; PAPD, passive aggressive PD; BPD, borderline PD; HPD, histrionic PD; NPD, narcissistic PD; AVPD, avoidant PD; SDPD, self-defeating PD.

5 A profile analysis of personality disorders 377 Table 2. Configuration of eight groups with 59 patients in the three-dimensional solution Dimension Group Detached Anankastic Phobic Dramatic Erratic Emotional Milder emotional Masochistic negativistic stress values for 59 points into three dimensions were The first dimension contrasted phobic and detached versus emotional and erratic. The second dimension placed erratic and detached at one end of the scale and anankastic and masochistic negativistic on the other. In the third dimension, dramatic and detached formed bipolarity. Only the second dimension had a significant association with the GAF score (r = 0.42, P < 0.01) and with total items (r = 0.42, P < 0.01). DISCUSSION Patterns of personality disorders Following cluster analysis, eight patterns of personality disorders emerged (Fig. 1), which included detached, dependent, and ambivalent types of Millon s model 44 and of Yorifuji s empirical study. 45 Also, we found two patterns of patients with borderline features, erratic (group 5) and emotional (group 6 and 7), which is compatible with the results of Barrash et al. 46 The structure of the cluster analysis was identical to that of Morey 47 who classified personalities, not patients, and two large groups of patients were differentiated: those who ruminate and those who act out. While there might be a greater or lesser number of patterns depending on the samples studied, what is important is the robustness of basic personality profiles across the settings. The results of this study will be strengthened by replication in different settings by different researchers. Hierarchy or profile In this study, each personality was found in several patient groups. For example, avoidant personality showed four patterns of co-variation: group 1, with schizoid and schizotypal personalities; group 2, with obsessive compulsive personality; group 3, with dependent personality; with group 6, borderline, dependent, and self-defeating personalities. Conversely, schizoid schizotypal patients always had avoidant features, and borderline patients inevitably showed avoidant, dependent, and selfdefeating features. This partly explains the considerable rate of multiple diagnoses. We propose that, to reduce unnecessary comorbidity, a hierarchical exclusion rule needs to be introduced in a current categorical-type model, 25 27,48,49 otherwise a profile should be used to describe personality disorders, adopting a dimensional-trait model. 23 Dimensional structure Widiger et al. illustrated the constellation of personality disorders. 32 In their schema, each patient is represented as a profile. In this study, we attempted to show a classification of these profiles, i.e., the constellation of patients. In MDS with 59 patients, three dimensions were identified: anxious rumination versus behavioural acting out, overall severity of personality pathology, and assertiveness versus withdrawal (Table 2). These dimensions are not identical but are related to some existing findings: the classical dichotomy of asthenia versus hysteria derived from Janet and reappearing with Jung, Eysenck, and Cloninger; the two dimensions of acting out and interpersonal involvement found by Blashfield et al.; 31 the two superordinate dimensions of affiliation and power of Interpersonal Circumplex (IPC); 23,24,32,55 and the three dimensions of involvement, assertiveness, and cognitive anxiety versus behavioural acting out as described by Widiger et al., 32 the three dimensions of harm avoidance, reward dependence, and novelty seeking of Cloninger, 56 the three dimensions of behavioural inhibition (trait anxiety), impulsivity, and fight/flight proposed by Gray, 57,58 the three dimensions of introversion-extraversion, neuroticism, and psychoticism found by Eysenck, 52,53 and the four dimensions consisting of DSM-III( R) three clusters plus obsessive personality found by Kass et al. 33 and Hyler et al. 34 In summary, most investigators identify similar dimensional structures besides severity in personality disorders. Severity of personality pathology Widiger et al. did not find severity of disturbance with patients in a state hospital setting who had

6 378 K. Nakao et al. little variation in level of dysfunction. 32 In our preliminary analysis of 37 patients with any personality disorder, the severity dimension, reflected in GAF and the total number of criteria fulfilled, was not found. It emerged only after 22 trait cases were included in the analysed sample. These cases are assumed to have either personality traits (patients have a relatively healthy personality), or an abnormal personality (a personality disorder but no impairment within their environment), a mixed personality disorder, or another personality disorder not described in DSM-III-R. While other dimensions classify the types of personality disorders, this dimension places healthier on one end and severely disordered on the other. It is this dimension, the dimension of impairment, 28,29 severity, 59 maturity of ego defense, 60 or relative mental health, 12 that differentiates personality disorder from personality. We believe that severity should be evaluated in the assessment of personality disorder. Classification system for personality disorder versus personality Since DSM-III-R Axis II is a frame of reference of personality disorder, we were strict in noting enduring patterns and pervasiveness ( redundancy since adolescence in every situation was emphasized) with high threshold ( clinical significance was required) in assessing each criterion. These strict limits led to a comparatively low number of diagnoses assigned. 1 8 This seems appropriate for a clinically relevant study of personality disorders that requires impairment, but it does not promise accuracy for a statistical study of abnormal personalities that involves extremes of personality traits. 28,29 These two may be associated but not identical, since the point at which any particular personality trait makes an individual dysfunctional varies by the trait, by the individual, and by the situation. Studies conducted in the UK assume that abnormal personality is merely an extreme manifestation of a normal trait and that the dimensional structures in people with and without abnormal personality are identical, which is validated empirically The DSM-III-R Axis II, however, might have different dimensional structures in people with and without personality disorder, since they consist of pathological traits as well as normal traits 69 so that distribution curve is skewed, if not bimodal. Classification of normal personality can be systematic, but that of personality disorder can not always be so. 28,29 Limitation This study has several limitations. Firstly, subjects were recruited from psychiatric out-patients, not from the general population. Also, sample size was small, and no patients fulfilled antisocial or sadistic personality criteria items. These limit the generalizability of our findings, especially in examining whether personality disorder is merely an extreme manifestation of a normal trait. Secondly, no structured interview was used. To overcome this, every criterion was evaluated using all available data. Nevertheless, caution is required as reliability of personality disorder diagnoses is reportedly low without a structured interview. 70 Thirdly, we selected patients with four or more total items for data analysis. However, criteria in DSM-III- R Axis II are set for each personality disorder category. Therefore, this decision could be regarded as arbitrary, though we confirmed that patients with fewer personality criteria items clustered together. Finally, this research does not address the issue of adequacy of each personality criteria item or personality disorder category itself described in DSM- III-R. CONCLUSION Cluster analysis yielded eight typologies of patients: detached (schizoid, schizotypal, avoidant, and paranoid), anankastic (obsessive compulsive and avoidant), phobic (avoidant and dependent), dramatic (narcissistic and histrionic), erratic (borderline, paranoid, and narcissistic), emotional (borderline, avoidant, dependent, and self-defeating), milder emotional (borderline, histrionic, and dependent), and masochistic negativistic (passive aggressive and selfdefeating). Multidimensional scaling identified the dimensions of classifying patients: anxious rumination versus behavioural acting out, overall severity of personality pathology, and assertiveness versus withdrawal. Current classification systems for personality disorders will be improved by either using a hierarchy in a categorical-type model, or by adopting a dimensional-trait model, with a dimensional rating for severity of psychopathology to define personality disorder. ACKNOWLEDGMENTS The authors are grateful to Drs John G. Gunderson, James Reich, and Theodore Millon for their kind comments on the earlier version of this manuscript.

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