The Bipolar Spectrum

Introduction

A question that is often asked is 'what's the difference between bipolar I and bipolar II?' The answer is not always clear, and it is known that many doctors do not make a distinction between the two. What is generally thought of as 'manic depression' or 'bipolar affective disorder' is actually a rather narrow definition of the condition. A number of doctors and researchers believe is more helpful to think of a 'bipolar spectrum.' They suggest that a much broader concept of bipolarity is needed. In effect, a spectrum, which takes into account all mood disorders. It would include, at one end of the spectrum, extreme psychotic manic states, and at the other, recurring depressions with relatively mild changes in temperament or mood. Angst (1998) argues for the need to enlarge bipolarity at the severe (psychotic manic) and the subthreshold (brief hypomania) ends of the spectrum.

MDF audioThe view is that this, more comprehensive, definition is likely to be beneficial in terms of earlier diagnoses and identifying more effective treatment options. For example, a longstanding concern has been that people experiencing less severe symptoms of bipolar disorder may be incorrectly diagnosed - in turn, leading to less effective treatment. A study conducted by the National Institute of Mental Health (Rockville, Md) found that 12.5% of patients initially given a diagnosis of major depression eventually were found to have a bipolar illness. This is an important finding, as people diagnosed with bipolar disorder are less likely than people with unipolar depression to respond to antidepressants (when they are used alone). For some people, the use of an antidepressant without a mood stabiliser has resulted in a manic episode. The notion of a 'bipolar spectrum' (which includes less severe symptoms of manic depression) is able to address this issue. The definition of bi-polar disorder would be much broader and, hopefully, the incidence of incorrect diagnoses far fewer. The problem would appear to be, however, that for this to happen doctors must take a much broader view of what constitutes 'bipolarity'. Most people with bipolar disorder go to see their GP during a depressive episode, which means that milder periods of expansive mood may not be recognized unless the doctor asks more detailed questions to uncover this information.

With this broader definition it follows that the incidence of manic depression would be much higher than we have previously believed to be the case. Some researchers have suggested between 4% and 5% of the population would fall within the categories of the bipolar spectrum. Dr Andrew Cutler (speaking at the Bipolar Disorders Update Symposium in Boston) advised doctors to avoid thinking of "manic depression as the same kind of illness that needs the same kind of treatment." Calling it an "incredibly complicated, varied illness," he divided it into subtypes: As much as 40% classic manic depression; between 40% and 50%, mixed (features of mania and depression); 15% to 20%, rapid cycling; and approximately 5% hypomania or cyclothymia. He stressed that subtypes of the illness may respond preferentially to specific medications. He found, for example, that lithium works better for classic or pure manic depression, or certain manias, than for mixed, complicated, or rapid-cycling states.
It has taken, on average, 10 years for MDF members to get an accurate diagnosis.
Greater awareness and understanding of the bipolar spectrum is likely to significantly reduce this. Given the importance of early diagnosis and treatment in md, this is an important step forward.

Criteria

Akiskal and Mallya suggest that the bipolar spectrum would include all of the following diagnostic categories:

  • Schizobipolar disorder (which is a hybrid of schizophrenia and bipolar disorder)
  • Mania
  • Depressions with hypomania (i.e. less severe mania) -irrespective of the duration
  • Hypomania which was first experienced as a result of taking medication
  • Depressions in association with cyclothymic and hyperthymic temperaments
  • Recurrent (pseudo-unipolar) depressions with bipolar family history
  • Signs and Symptoms of a Hypomanic Episode

Three or more of the following, which must represent a change from one's usual temperament and behaviour for 2 days or more.

  • Cheerfulness and jocularity
  • Gregariousness and people-seeking
  • Heightened sexual drive and behaviour
  • Talkativeness
  • Overconfidence and overoptimism
  • Disinhibition and carefree attitudes
  • Hyposomnia (oversleeping)
  • Eutonia (increased sense of physical fitness) and vitality
  • Overinvolvement in new projects
  • Criteria for the Cyclothymic Temperament
  • Biphasic mood swings -- abrupt shifts from one mood phase to the other, each phase lasting for a few days at a time with little stability between episodes

One would expect to see at least four of the following:

  • Lethargy alternating with eutonia (increased sense of physical fitness)
  • Shaky self-esteem alternating between low self-confidence and overconfidence
  • Decreased verbal output alternating with talkativeness
  • Mental confusion alternating with sharpened and creative thinking
  • Unexplained tearfulness alternating with excessive punning and jocularity
  • Introverted self-absorption alternating with uninhibited socialising

Attributes of the Hyperthymic Temperament

Four or more of the following attributes, which are not a part of an episode, and do not describe how the person usually is.

  • Upbeat and exuberant
  • Articulate and jocular
  • Overoptimistic and carefree
  • Overconfident and boastful
  • High energy level, full of plans and improvident activities
  • Versatile with broad interests
  • Overinvolved and meddlesome
  • Uninhibited and risk-taking
  • Habitual short sleeper (less than 6 hours/night)

References

Akiskal HS. Bipolar spectrum: Clinical and familial validation. Program and abstracts of the 154th Annual Meeting of the American Psychiatric Association; May 5-10, 2001; New Orleans, Louisiana. Industry Symposium 45B.

Akiskal HS, Mallya G: Criteria for the "soft" bipolar spectrum: treatment implications. Psychopharmacol Bull 23:68-73, 1987.

Akiskal HS, Placidi GF, Signoretta S, Ligouri A, Gervasi R, Maremmani I, Mallya G, Puzantian VR: TEMPS-I: Delineating the most discriminant traits of cyclothymic, depressive, irritable and hyperthymic temperaments in a nonpatient population. J Affect Disord 51:7-19, 1998.

Angst J: The emerging epidemiology of hypomania and bipolar II disorder. J Affect Disord 50:143-151, 1998. Cassano GB, Akiskal HS, Savino M, Musetti L, Perugi G, Soriani A: Proposed subtypes of bipolar II and related disorders: With hypomanic episodes (or cyclothymia) and with hyperthymic temperament. J Affect Disord 26:127-40, 1992.

Depue RA, Slater JF, Wolfsetter-Kausch H: A behavioural paradigm for identifying persons at risk for bipolar disorder: a conceptual framework and five validation studies. J Abnorm Psychol 90:381-437, 1981. Eckblad M, Chapman LJ: Development and validation of a scale for hypomanic personality. J Abnorm Psychol 95:214-22, 1986.

J. Sloan Manning, MD; Pamela D. Connor, PhD; Anjali Sahai, MD A Review of Current Concepts and Implications for the Management of Depression in Primary Care. Archives of Family Medicine Vol. 7 No. 1, January/February 1998