Differences between bipolar disorder type I and II
We analyze the differences between the subtypes of this psychological disorder.
Bipolar disorder is an important mental health problem, characterized by the occurrence of acute episodes of clinically relevant sadness and mood expansion, but whose expression may be different depending on the subtype diagnosed.
The differences between the types are notable, and in order to determine precisely which of the two is being suffered, it is necessary to make an in-depth review of both the symptoms present and their history.
In addition, there is a third type: cyclothymia. In this particular case the symptoms are of lesser intensity for each of its poles, although it also generates a substantial impact on different areas of life.
In this article we will address the differences between bipolar disorder type I and II, in order to shed light on the issue and contribute to the accuracy in the diagnosis or treatment process, which are key to influence its clinical and prognosis.
General characteristics of the subtypes of bipolar disorder
Before delving into the differences between bipolar disorder type I and II, it is important to know the main characteristics of each of the disorders that form the category of bipolar disorder.. In general, these are problems that may begin in adolescence. In fact, in the event that depression is present in this period, it can be understood as one of the risk factors for bipolarity in the future (although never in a determinant way).
Bipolar disorder type I has, as a distinctive feature, a history of at least one manic episode in the past or present (mood expansion, irritability and excessive activity), which may alternate with stages of depression (sadness and difficulty in experiencing pleasure). Both extremes reach a very high severity, so that they can even provoke psychotic symptoms (especially in the context of mania).
Bipolar disorder type II is characterized by the presence of at least one hypomanic phase (of lesser impact than mania but with similar expression) and one depressive phase, which are interspersed in no apparent order. For this diagnosis it is necessary that there has never been a previous manic episode, otherwise it would be a subtype I. To make this nuance requires an analysis in great depth of past experiences, because the mania can pass unnoticed.
Cyclothymia would be equivalent to dysthymia, but from a bipolar perspective. In this same line, acute phases of mild depression and hypomania would concur, whose intensity and/or impact would not allow the diagnosis of any of them separately (subclinical symptoms). The situation would be maintained for at least two years, generating disturbances in the quality of life and/or participation in meaningful activities.
Finally, there is an undifferentiated type, which would include people who present symptoms of bipolar disorder but do not meet any of the diagnoses described above.
Differences between bipolar disorder type I and II
Bipolar disorder type I and type II, together with cyclothymia and undifferentiated bipolar disorder, are the conditions included in the category of bipolar disorder (formerly known as manic-depressive). Although they belong to the same family, there are important differences between them that must be taken into account, since a proper diagnosis is essential to provide treatment tailored to the care needs of each case.
In this article we will discuss the possible differences in epidemiological variables, such as gender distribution and the distribution by sex.We will discuss possible differences in epidemiological variables, such as gender distribution and prevalence, as well as other clinical factors, such as depressive, manic and psychotic symptoms. Finally, the specific form of presentation (number of episodes) and severity of each case will be discussed. The particularity of cyclothymia will also be discussed.
1. Gender distribution
There are data suggesting that major depression, the most common of the problems included in the category of mood disorders, is more common in women than in men. The same occurs with other psychopathologies, such as those included in the clinical spectrum of anxiety.
However, in the case of bipolar disorder there are slight differences with respect to this trend: the data suggest that men and women suffer with the same frequency from type I, but the same is not true for type II.
In this case, women are the most at-risk population, as is the case with cyclothymia. They are also more prone to mood changes associated with the time of year (seasonal sensitivity). Such findings are subject to discrepancies depending on the country in which the study is conducted.
Bipolar disorder type I is slightly more frequent than type II, with a prevalence of 0.6% vs. 0.4%, according to meta-analyses.according to meta-analysis. It is, therefore, a relatively common health problem. In general (if both modalities are considered at the same time), it is estimated that up to 1% of the population may suffer from it, a figure similar to that observed in other mental health problems different from this one (such as schizophrenia).
3. Depressive symptoms
Depressive symptoms can occur in both bipolar disorder type I and type II, but there are important differences between the two that must be taken into consideration.. The first of these is that in bipolar disorder type I this symptom is not necessary for diagnosis, although a very high percentage of people who suffer from it end up experiencing it at some time (more than 90%). In principle, only one manic episode is required to corroborate this disorder.
In bipolar disorder type II, on the other hand, its presence is mandatory. The sufferer must have experienced it at least once. In general, it tends to appear recurrently, interspersed with periods in which the mood acquires a different sign: hypomania. In addition, it has been observed that depression in type II tends to be longer lasting than in type I, this being another of its distinguishing features.
In the case of cyclothymia, the intensity of depressive symptoms never reaches the threshold of clinical relevance, contrary to what happens in bipolar disorders type I and II. In fact, this is one of the main differences between cyclothymia and type II.
4. Manic symptoms
Expansive, occasionally irritable mood is a common phenomenon in bipolar disorder in any of its subtypes.. It is not an exultant joy, nor is it associated with a state of euphoria congruent with an objective fact, but it acquires a disabling intensity and does not correspond to precipitating events that can be identified as its cause.
In the case of bipolar disorder type I, mania is a necessary symptom for diagnosis. It is characterized by a state of extreme expansiveness and omnipotence, resulting in impulsive acts based on disinhibition and a sense of invulnerability. The person is excessively active, engaged in an activity to the point of forgetting to sleep or eat, and engaging in acts that involve potential risk or that may have serious consequences.
In bipolar disorder type II the symptom exists, but does not present with the same intensity. In this case a great expansion is shown, in contrast to the mood that is usually displayed, occasionally acting in an expansive and irritable manner. Despite this, the symptom does not have the same impact on life as the manic episode, so it is considered a milder version of it. As was the case in bipolar disorder type I with respect to mania, hypomania is also necessary for the diagnosis of type II.
5. Psychotic symptoms
Most of the psychotic phenomena associated with bipolar disorder are triggered in the context of manic episodes.. In this case, the severity of the symptom can reach the point of breaking the perception of reality, in such a way that the person forges delusional beliefs about his/her abilities or personal relevance (considering him/herself as someone so important that others should address him/her in a special way, or assuring that he/she has a relationship with well-known figures in art or politics, for example).
In hypomanic episodes, associated with type II, there is never enough severity for such symptoms to be expressed. In fact, if they were to appear in a person with bipolar disorder type II, they would suggest that what is really being suffered is a manic episode, so the diagnosis should be changed to bipolar disorder type I.
6. Number of episodes
It is estimated that the average number of episodes of mania, hypomania or depression that the person will suffer during his life is nine. However, there are evident differences among those suffering from this diagnosis, which are due to both their physiology and their habits. Thus, for example, those who use illegal drugs have a higher risk of experiencing clinical mood swings, as well as those with poor adherence to pharmacological and/or psychological treatment. In this sense, there are no differences between subtypes I and II.
In some cases, certain individuals may express a peculiar course for their bipolar disorder, in which a very high number of acute episodes of both mania and hypomania are observed.of mania, hypomania or depression. These are rapid cyclers, who present up to four clinically relevant swings in each year of their lives. This form of presentation can be associated with both type I and type II bipolar disorder.
It is possible that, after reading this article, many people may conclude that type I bipolar disorder is more severe than type II, since the intensity of manic symptoms is greater in the former. What is actually true is that this is not exactly so, and that subtype II should never be considered as the mild form of bipolar disorder. In both cases there are significant difficulties in daily life, and therefore there is a general consensus on their equivalence in terms of severity.
While in subtype I the episodes of mania are of greater severity, in type II depression is of obligatory presence and its duration is greater than in type I.. On the other hand, in type I psychotic episodes may arise during the manic phases, which imply complementary perspectives of intervention.
As can be seen, each type has its particularities, so it is essential to articulate an effective and personalized therapeutic procedure that respects the individuality of the sufferer. In any case, the selection of a psychological approach and a drug should be adjusted to the care needs (although mood stabilizers or anticonvulsants are necessary), with an impact on the way in which the person lives with his or her mental health problem.
- Hilty, D.M., Leamon, M.H., Lim, R.F., Kelly, R.H. and Hales, R.E. (2006). A Review of Bipolar Disorder in Adults. Psychiatry (Edgmont), 3(9), 43-55.
- Phillips, M.L. and Kupfer, D.J. (2013). Bipolar Disorder Diagnosis: Challenges and Future Directions. Lancet, 381(9878), 1663-1671.
(Updated at Mar 28 / 2023)