On the homogeneity of personality disorder clusters

Incidence and comorbidity of personality disorders among first ever admitted psychiatric patients

During a period of one year, 157 first ever admitted psychiatric patients in the age group 18-49 years from a catchment area of 217,649 persons were interviewed with the Present State Examination 10th edition, development version and the Personality Disorder Examination, 1988 version. Of the sample, 23% received at least one DSM III-R personality disorder (PD) diagnosis. Rates avoidant PD, very few borderline PDs were found. Almost all patients with PDs also had major psychiatric disorders and the sample was biased towards younger individuals with more severe Axis I symptomatology compared with first ever admitted psychiatric patients aged 18-49 years in Denmark. Cluster A was associated with schizophrenia, cluster B with alcohol or other substance use disorders, and cluster C with anxiety disorders. Within Axis II, schizotypal PD was associated with avoidant and dependent PD, and paranoid with antisocial and dependent PD.

Problem-solving ability and comorbid personality disorders in depressed outpatients

Major depressive disorder (MDD) is associated with poor problem-solving abilities. In addition, certain personality disorders (PDs) that are common among patients with MDD are also associated with limited problem-solving skills. Attempts to understand the relationship between PDs and problem solving can be complicated by the presence of acute MDD. Our objective in this study was to investigate the relationships between PDs, problem-solving skills, and response to treatment among outpatients with MDD. We enrolled 312 outpatients with MDD in an open, fixed-dose, 8-week fluoxetine trial. PD diagnoses were ascertained via structured clinical interview before and after fluoxetine treatment. Subjects completed the Problem-Solving Inventory (PSI) at both time points. We used analyses of covariance (ANCOVAs) to assess relationships between PD diagnoses and PSI scores prior to treatment. Subjects were divided into three groups: those with PD diagnoses that remained stable after fluoxetine treatment (N=91), those who no longer met PD criteria after fluoxetine treatment (N=119), and those who did not meet criteria for a PD at any time point in the study (N=95). We used multiple chi(2) analyses to compare rates of MDD response and remission between the three PD groups. ANCOVA was also used to compare posttreatment PSI scores between PD groups. Prior to fluoxetine treatment, patients with avoidant, dependent, narcissistic, and borderline PDs reported significantly worse problem-solving ability than did patients without any PDs. Only subjects with dependent PD remained associated with poorer baseline problem-solving reports after the effects of baseline depression severity were controlled. Patients with stable PD diagnoses had significantly lower rates of MDD remission. Across PD groups, problem solving improved as MDD improved. No significant differences in posttreatment problem-solving were found between PD groups after controlling for baseline depression severity, baseline PSI score, and response to treatment. Treatment with fluoxetine is less likely to lead to remission of MDD in patients with stable PDs. More study is needed to investigate causal links between PDs, problem solving, and MDD treatment response.

Possible correlates of DSM-III-R personality disorders

An association between personality disorder (PD) pathology, including symptoms of all PD types and Axis I disorders, and suicidal behaviour was studied in a series of 90 non-schizophrenic, non-bipolar in-patients of both sexes without mental retardation or organic brain syndrome. All of these patients, who scored positively on the SCID-II-PQ, were interviewed with the PDE and SCID-P, and with the Structured interview for the study of childhood trauma provided with supplementary items reflecting suicidal behaviour. Mood disorders were found to be significantly correlated with cluster C pathology (PD pathology always being expressed by dimensional PDE scores) and eating disorders were significantly correlated with cluster B pathology in women. Psychoactive substance use disorders were mainly correlated with cluster B pathology and anxiety disorders with cluster C pathology in both sexes. Suicidal behaviour was correlated with PD pathology of all clusters in women, but not in men. In women a strong correlation was found between suicidal behaviour and history of childhood trauma, especially sexual abuse. The results of this study indicate that there is some specificity with regard to the Axis I/Axis II association, more so in relation to PD clusters than in relation to the individual PD types. However, the relationships between PD pathology and Axis I disorders and suicidal behaviour are complex, and they differ between the sexes.