Dr. Patrick J. Hart
Identification & Treatment of Substance Induced Mood Disorders

Differential Diagnosis:
Substance Induced Mood Disorder and Personality Disorders
    One of the primary debates surrounding the diagnosis of Bipolar II Disorder concerns its comorbidity with personality disorders.  In bipolar diagnoses, comorbidity with Personality Disorders has been reported at varying rates.  Ucok, et al, (1998) indicate that epidemilological surveys using DSM-III criteria, have estimated the prevalence of overall personality disorders from 10% to 13% in outpatient clinical populations.  In the 1980’s comorbidity rates between Bipolar I and Personality Disorders were reported at 4% to 12%, yet more recently such rates have been reported to be significantly higher at 47.7% (Ucok, 1998). 

   One reason for such differences in reports of comorbidity rates may be due to the varying methodologies used for assessment of personality disorders and to changes in DSM-IV diagnostic nomenclature.  Assessment methods vary from self-report measures, to structured interviews, and the need for more definitive research is apparent. 

One recent study indicates that:  “It has been found that the majority of personality disorders associated with Bipolar II Disorder are from clusters B (histrionic, borderline, narcissistic, antisocial) in bipolars, and cluster C (avoidant, dependent, passive-aggressive, obsessive-compulsive) in unipolars” (Ucok, et al., 1998, p. 72).  These authors report that 47.5% of bipolar I subjects in this study were noted for at least one Personality Disorder, as compared to a 15.5% in control subjects.  Although the authors provide no statistic, it is noteworthy that suicide attempts were more frequent in patients with a history of Personality Disorder diagnoses.  The authors also indicate that patients with Bipolar I Disorder in remission have personality traits that differ from those of normal controls.  Unfortunately, the authors do not elaborate upon these differences; yet they conclude that: “These results suggest that the comorbidity of personality disorders with Bipolar Disorder predicts a poor treatment outcome” (p. 74).

Differential Diagnosis: Bipolar II Disorder and Personality Disorders
    The discerning clinician will make clinical judgments carefully when diagnosis involves closely associated and potentially “comorbid” clinical pictures.  This is especially true in differentiating diagnoses of Personality Disorders and Bipolar Disorders.  The General Diagnostic Criteria for a Assessing Personality Disorders (APA, 1994, p. 633) specifically emphasizes “enduring patterns of behavior” as the definitive aspect of diagnostic decisions.  Just the opposite is true in Bipolar II Disorder.

    Vigilant assessors are aware that the “enduring patterns” associated with Personality Disorders may contradict the diagnosis of Bipolar II Disorder.  Recall that  “hypomania,” the essential feature of Bipolar II Disorder, must be associated with an:  “...  unequivocal change in functioning that is uncharacteristic of the person when not symptomatic (APA, 1994, p. 338). This nuance, alone, provides evaluating psychologists a critical and important clinical discernment. 

   Having had person-to-person contact with the “euphoric—grandiose,”  “over enthusiastic” and “expansive quality of mood disturbance” described here as hypomanic; I will assure you this—given the above descriptors—you (the astute psychologist) will recognize a Hypomanic Episode when you see it! 

    Recent research has revealed that only 5% to 15% of patients noted for Bipolar II Disorder develop a full-blown Manic Episode that ultimately warrants a diagnosis of  Bipolar I Disorder (Vieta, et al, 1997).  These authors indicate remarkable differences exist between Bipolar I and II patients.  Their research showed that Bipolar II Disorder tended to be more severe in terms of episode frequency, however, symptom severity was found to be clearly greater in Bipolar I Disorder.  The authors conclude:  “Bipolar II Disorder could be described as a milder form of manic-depressive illness regarding symptom severity, but as a more malignant form concerning episode frequency” (p. 99).


  Psychologists and substance abuse counselors must also have the ability to skillfully distinguish Bipolar I and Bipolar II Disorder from episodes of Substance Induced Mood Disorder, Mood Disorder Due to a General Medical Condition,  Dysthymic Disorder, Cyclothymic Disorder, Psychotic Disorder and Bipolar I Disorder (APA, 1994, pp. 361-362).  The essential features of Manic and Hypomanic Episodes define the distinguishing attributes of Bipolar Disorders in all considerations of differential diagnosis.


Dr. Patrick J. Hart
206-547-HELP
206-769-STOP
Substance Abuse & Chemical Dependency Assessment in Seattle