Depression is one of the most prevalent mental disorders worldwide.. Specifically, and according to WHO, it is the leading cause of disability and sick leave in the world.
Depression is characterized by deep sadness, an inability to enjoy things that once produced pleasure (a symptom called anhedonia), and many other symptoms, such as guilt or apathy.
Depression can manifest itself in many ways in terms of symptoms and course. In this article we will learn about the different types of depression according to five criteriathe number of episodes, the type of episodes, the symptoms, the onset/course and the new specifications of the disorder proposed by the DSM-5.
What is depressive disorder?
Before we see what types of depression exist according to the above-mentioned parameters, let’s take a brief look at what depression (or depressive disorder) consists of.
Depression is a mood disorder, classified as such in the DSM-IV-TR.. In DSM-5In addition, the category of depressive disorders is created (as an independent category), which includes a series of disorders with depressive symptomatology.
The prototypical disorder is depression, with the presence of psychic (sadness, unhappiness…), motivational and behavioural (inhibition, apathy…), cognitive (altered performance and deficits in attention and memory, among others), physical (sleep problems, fatigue…) and interpersonal (deterioration in personal relationships, rejection…) symptoms.
In DSM-5, the classically known depression is conceptualized as “major depressive disorder. That is why in this article we will speak indistinctly of “depression” and “depressive disorder”, being here interchangeable terms.
Types of depression
We are going to analyze the different types of depression, according to four different parameters or criteria.
According to the number of episodes
Depending on the number of depressive episodes, we will talk about different types of depression. It is worth mentioning that a depressive episode involves the appearance of depressive symptoms (according to DSM-5, five or more symptoms) for a minimum of two weeks; the symptoms, in addition, must appear almost every day, and cause significant discomfort to the patient.
1.1. Single-episode major depressive disorder
The first type of depression according to the number of episodes is the single episode, and is characterized by the fact that the person has only had (or is currently having) one depressive episode, with no previous history of depressive episodes.
1.2. Recurrent major depressive disorder
In the event that two or more depressive episodes have appeared over time, we would diagnose a major relapsing depressive disorder, which implies that the depression is relapsing.
2. Depending on the type of episodes
This is perhaps the best-known classification for types of depression. In this case, the criterion is based on the type of episode(s) that the patient presents (or has presented). We find two: bipolar depression and unipolar depression.
2.1. Bipolar depression
Bipolar depression is characterized by the patient having (or having) a manic or hypomanic episode.in addition to the depressive episode. The two types of episodes occur with a specific time frame. This type of depression is so called because the person has been at both poles (bi-polar); the depressive and the manic.
This type of disorder occurs equally frequently between men and women, in a 1/1 relationship. The average age of onset is 20 years. On the other hand, the percentage represented by bipolar depressions in relation to total mood disorders is 10%.
Continuing with the types of depression according to the episodes presented by the patient, we find the second: unipolar depression. It is characterized by only depressive episodes (never manic or hypomanic); that is, the patient has only been in “one pole”.
Unlike the previous one, it occurs more frequently in women than in men, in a ratio of 2/1. In addition, its onset is later (the average age of onset is 35 years). Finally, in the case of unipolar depression, the percentage of unipolar depression in relation to all mood disorders is 90%, i.e., the vast majority of cases.
Depending on the symptoms
Depending on the type of symptoms that appear, in addition to “classic” major depressive disorder, there are two other types of depression: atypical depression and melancholic depression.
In addition, these two types of depression are DSM-IV-TR disorder-specific specifications (i.e., when making the diagnosis of a depression, it can be specified whether it is melancholic or atypical, if it corresponds to one of these two types).
3.1. Atypical depression
Atypical depression is characterized by a series of specific symptoms, such as mood reactivity to positive situations.The condition is associated with at least two of the following symptoms: weight gain or appetite, discouragement (feeling heavy or inert limbs), hypersomnia (a great need for sleep), and a prolonged pattern of sensitivity to interpersonal rejection (which causes significant social decline).
In addition, atypical depression has the characteristic that it responds very well to pharmacological treatment with MAOI (monoamine oxidase inhibitors) antidepressants.
3.2. Melancholic depression
Following the types of depression according to their symptomatology, we find the melancholic depression, which is characterized by a peculiar pattern of symptoms: it appears especially a major vegetative component, coupled with symptoms such as anhedonia. Unlike atypical depression, melancholic depression responds very well to treatment with tricyclic antidepressants and ECT (Electroconvulsive Therapy).
Thus, broadly speaking, a person with melancholy depression will usually feel worse in the mornings, will have early awakenings (before the “usual” time the person used to wake up to), psychomotor slowing or agitation, anorexia or weight loss, and excessive or inappropriate guilt.
Coupled with all (or some) of these symptoms, there is also a depressive mood, qualitatively different from that which typically appears in depression.
4. Depending on start/course
Following a third criterion to classify the different types of depression, we find different depressions according to their beginning and/or course.
4.1. Postpartum onset depression
This type of depression appears in the first four weeks of postpartum, according to the DSM-IV-TR, and in the peripartum period (which includes pregnancy), according to the DSM-5. Specifically, this is a depression specification in the DSM-IV-TR.
It affects a large number of women, and its aetiology has been related to biological and hormonal factors, mainly.
Depression with seasonal pattern
Seasonal pattern depression entails a sustained temporal relationship between the onset of depressive episodes and a time of year; this means that episodes usually appear in a particular season (or time) of the year.
On the other hand, and according to diagnostic criteria (since this type of depression is also a specification of depressive disorder in the DSM-IV-TR), remissions of the disorder (or pole change, in the case of bipolar disorder) also occur at a certain time of year.
In order to establish this specification together with the diagnosis of depressive disorder, it is required that in the last two years there have been at least two seasonal episodes and none non-seasonal. In addition, such episodes are required to be majoritarian in the patient’s life.
5. According to DSM-5 specifications
So far we have been commenting on different types of depression, according to different criteria, and according to some depression specifications that appear in the DSM-IV-TR. However, DSM-5 introduces two new specifications for depressive disorderand with them, we find two new types of depression.
Depression with anxious malaise
According to the DSM-5, this type of depression is characterized by the classic symptoms of depression, coupled with at least two symptoms of the anxious type, such as: a feeling of nervousness or tension, difficulty concentrating (due to worry), fear of something terrible happening, feeling of being able to lose control at any time, and feeling of unusual tiredness.
In addition, this type of depression requires specifying the severity of the disorder: mild (if 2 of the anxious symptoms mentioned appear), moderate (if 3 appear), moderate/severe (if 4 or 5 appear), and severe (if 4 or 5 appear next to a state of agitation).
Depression with mixed symptoms
Depression with mixed symptoms, according to the DSM-5, is characterized by meeting criteria for the depressive episode, and by meeting at least 3 diagnostic criteria for another episode, the latter being a manic, hypomanic or mixed episode.
American Psychiatric Association (APA). (2000). DSM-IV-TR. Barcelona: Masson.
American Psychiatric Association -APA- (2014). DSM-5. Diagnostic and statistical manual of mental disorders. Madrid: Panamericana.
Belloch, A.; Sandín, B. and Ramos, F. (2010). Manual of Psychopathology. Volume I and II. Madrid: McGraw-Hill.