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Affective Spectrum Disorders Bipolar Spectrum
The Manic Wing of the Bipolar Spectrum
a report by
Jules Angst
1
and Petra Zimmermann
2
1. Professor of Psychiatry, Zurich University; 2. Molecular Psychology Unit, Max Planck Institute of Psychiatry, Munich
The International Statistical Classification of Diseases and Related Epidemiology
Health Problems, 10th Revision (ICD-10) allows a very detailed The Early Developmental Stages of Psychopathology (EDSP) study, a
diagnostic classification of affective disorders on the syndromal level prospective community survey of 3,021 adolescents and young adults,
into the three classic groups of manic, bipolar and depressive episodes. found lifetime prevalence rates of 1.5% for mania at baseline. Most
The method also takes into account severity (psychotic, severe, subjects with mania fulfilled the criteria for more than one episode
moderate and mild) and recurrence. However, a shortcoming is that (prevalence rate 1.4%). The prevalence of hypomanic episodes was
the ICD-10 labels the groups of manic and hypomanic (F30) and 2.0% at baseline, but only 0.4% manifested with a concomitant major
depressive syndromes (F32) as episodes only (rather than disorders), depressive episode; the others showed m.
5,6
Within bipolar-I disorder,
whereas bipolar manifestations are ranked as a fully-fledged disorder Md and M have been described as being relatively rare. The only data so
(F31). The finely graded classification of ICD-10 has so far had far available on cumulative incidence rates are again derived from the
regrettably little influence on clinical, psychopharmacological and EDSP. After a 10-year follow-up (n=2,210; T0–T3 response rate = 73%),
biological research. The literature is instead dominated by a simplified 65 subjects with Diagnostic and Statistical Manual of Mental Disorders
classification of affective disorders into major depressive disorders (DSM-IV)-defined manic episodes were identified, corresponding to a
(MDD) and bipolar-I and bipolar-II disorders. In particular, research into lifetime prevalence rate of 3% (2.97%). Surprisingly, 40% of manic
pure mania (M) and mania with moderate or mild depression (Md) is subjects who would usually be labelled as suffering from bipolar-I
very limited, and there has been virtually no investigation of pure disorder did not meet the strict criteria for mania with major depressive
hypomania (m) without depression or of minor bipolar disorder episodes (MD), but only for Md or M. The corresponding weighted
(md/MinBP, defined by the lifetime co-occurrence of mild or moderate prevalence rates were 1.79% (MD), 0.58% (Md) and 0.60% (M).
depression with hypomanic episodes or by cyclothymic disorder).
For these reasons, this article can provide only limited data and Studies of Manic Patients without Long-term Follow-up
provisional conclusions. In the earlier literature, as summarised by Shulman and Tohen,
3
retrospective studies of treated manic patients predominate. Abrams et al.
7
Pure Mania found more males among pure manic patients and an increased morbid
The literature on mania is both extensive and heterogenous, and consists risk for unipolar depression among their relatives. Nurnberger et al.
8
largely of studies assessing manic episodes within bipolar-I disorder. The examined 241 patients attending a lithium clinic, 38 of whom were
drug trials on mania rarely distinguish between M and mania as an suffering from M. Sixty-three manics had been treated but not hospitalised
element of bipolar-I disorder; therefore, they are dealing with for depression (Md) and 140 manics had been hospitalised for depression
heterogeneous samples. A recent review of a study by Harish et al. in (group MD). There was a trend (p<0.10) towards a gender difference: 66%
2005 summarised the literature comprehensively.
1
Very few modern of M sufferers, 51% of Md sufferers and 46% of MD sufferers were male.
studies focus on M, but some of them will be reviewed here. The
diagnosis of unipolar M (without mild or severe depression) is a function
of the duration of the follow-up. Just as with recurrent severe
Jules Angst is Emeritus Professor of Psychiatry at Zurich
University and an Honorary Doctor of Heidelberg
depression, where the risk of a diagnostic conversion to bipolar disorder
University. His work focuses on epidemiological and
remains constant over a patient’s lifetime,
2
every new episode of mania clinical research. Prior to this, from 1969 to 1994, he was
carries with it the risk of a diagnostic conversion to bipolar disorder. This
a Professor of Clinical Psychiatry and Head of the
Research Department of Zurich University Psychiatric
is why some authors have proposed a minimum number of manic
Hospital (the Burghölzli). Professor Angst has received
episodes as a prerequisite for the diagnosis of M. For example, three
many awards in recognition of his work, including the
episodes and a minimum follow-up of three years,
3
or four episodes and
Selo Prize of the National Alliance for Research on
Schizophrenia and Depression (NARSAD) in 1994 and the Lifetime Achievement Award of
a minimum follow-up of four years,
4
might be defined as criteria for
the International Society of Psychiatric Genetics (ISPG) in 2002.
diagnosis. Such restrictions have proved to be of limited value in face of
E: jangst@bli.uzh.ch
the results of a recent survival analysis of the diagnostic conversion from
M to bipolar disorder. In a prospective study of manic patients
Petra Zimmermann is a Genetic Epidemiologist in the Molecular Psychology Unit of the Max
conducted over more than 20 years, we found a relatively constant
Planck Institute of Psychiatry. She studied psychology at the Julius-Maximilians-Universität
(linear) lifelong conversion rate of 2.7% per year among 33 hospitalised
Würzburg. Her doctoral thesis, conducted at the Max Planck Institute of Psychiatry, Munich,
patients whose illness began with mania. This risk is more than double
and at the Technical University of Dresden, was entitled ‘The effect of primary anxiety disorders
on alcohol use, abuse and dependence in adolescents and young adults’.
the 1.25% rate we reported for the diagnostic conversion from
depression to bipolar disorder.
2
© TOUCH BRIEFINGS 2008 19