Mood disorders are typically divided into Unipolar and Bipolar subtypes. Unipolar disorders cause recurrent mood disturbances in 'low' direction only: that of depression.
Bipolar Disorders are characterised by the radical mood swings from manias (feeling high, euphoric) to depressions (feeling low and hopeless). In this post, I will discuss different variations of these subtypes, their prevalence, causes and treatments.
*Featuring video with awesome Stephen Fry!*
Bipolar Disorders are characterised by the radical mood swings from manias (feeling high, euphoric) to depressions (feeling low and hopeless). In this post, I will discuss different variations of these subtypes, their prevalence, causes and treatments.
*Featuring video with awesome Stephen Fry!*
Unipolar mood disorders
Major Depression Episodes
Major depression is different from a depression caused by grieving or a negative event, as it does not necessarily occur for a specific reason and tends to reoccur in what is known as Major Depression Episodes (MEDs).
Major depression is a general term for a long-term depression. To be diagnosed, a person should have certain symptoms present most of the days for at least two weeks. These include: anhedonia (loss of interest and pleasure in everyday activities), disturbed sleeping patterns (either insomnia or hypersomnia), disturbed eating pattern (either loss of apetite or overeating), low mood and self esteem, feeling of guilt, loss of energy, motor agitation or retardation, difficulty concentrating, recurrent thoughts of suicide and death.
Dysthymia is often described as a chronic depression. It is characterised by almost constant low mood; the symptoms are . In order to be diagnosed with dysthymia, a person should have a dark, sad mood for most of the days for at least 2 years; in children and adolescents, the mood can be irritable instead, which should last for at least 1 year. In addition, at least two of the following symptoms should be present: disturbed sleeping pattern, change in eating habits, fatigue, low self-esteem.
Depression can be divided into:
a) Melancholic: the most severe type of depression. Its distinctive feature is a lack of mood reactivity: that is, a person's mood does not improve in reaction to positive events. Melancholic depressives may also ruminate over the same thoughts and experiences, and feel excessive guilt. Their depression takes on a life of its own: the more episodes they have, the more autonomous such episodes seem, less likely to be set off by stressful events.
b) Seasonal: depression which occurs at the same time each year, typically in autumn, winter or late spring.
c) Atypical: a condition in which one's mood elevates in response to positive events - something that does not happen in other types of depression. In addition, at least two of the following symptoms are present: weight gain, hypersomnia, heavy sensation in limbs (leaden paralysis) and extremely high interpersonal rejection sensitivity which often cause difficulties in relationships and at work.
d) Psychotic: this is yet another type of severe depression. It is similar to melancholic type, but is also accompanied by hallucinations and/or delusions which reflect the depressed mood and guilt that the patients feel (for example, they might hear a voice telling them they are worthless).
MDEs occur in 17% of population at some point of their lives; in the course of every single year, around 7% of the population are affected by the disorder. Depression is twice as common in women than in men.
MDEs can be subdivided by incident or recurrent. They reoccur in 80% of the patients, which means it is extremely hard to get rid of a depression entirely and to guarantee it would not come back at some point. Studies showed that the probability of an episode to reoccur increases with the number of years passed after the previous episode and the number of previous episodes.
Previously, it was thought that between the episodes patients were simply 'normal'. However, it has been suggested that the episodes leave a 'scar' which makes them more likely to relapse into depressive mood. In 1998, Judd et al. conducted an extensive 12-years study, in which he found that after an incident episode, patients were completely symptom-free only 54% of the weeks. Moreover, those who had suffered from a recurrent episode, were symptom-free mere 37% of the weeks.
Genetic factors
Studies have shown that biological relatives of those diagnosed with depression are three times more likely to have depression than those without family history of depression. According to the findings of twin studies, somewhere between 31%-42% of variance is due to genetic influences. It is actually even higher for more severe, recurrent depressions.
Cognitive factors
People with depression tend to have what is called a negative cognitive triad: they see themselves, environment/people around and future much more negatively than it is supported by facts or than the others see it. They also have distinct cognitive biases. For example, they tend to see the world in black and white, nothing in between; it is frequent mindset that if they are not the very best at something, it is not worth doing at all. Depressives are also prone to rumination: over-thinking and over-analysing their own feelings and emotions.
Environmental factors
Independent life events can contribute to the development of depression. In the Hurricane Katrina study, 2007, it was found that 49.1% of the residents of New Orleans (area most affected by the hurricane) suffered from depression symptoms of varying severity 30 days after the disaster - compared to 26.4% in the areas nearby.
Often depressives put themselves in danger or cause health problems due to poor social judgement, not taking care of themselves (e.g. proper nutrition, hygiene) and loss of motivation to perform at work or school.
Genes + Environment
In 2003, Capri et al. divided the participants by the type of their 5-HT transporter gene (serotonin, aka 'happiness', transporter) into those with SS (short-short), SL (short-long) and LL (long-long) genotypes. He then asked the participants about the number of stressful events that they had in their lives - such as loss of a close person, etc. What he found was that there was a strong relationship between the number of stressful events and the likelihood of getting a depression in those who had an SS genotype. This relationship was weaker in those with the SL genotype and much weaker - with LL one.
This finding demonstrates that those with SS genotype (i.e. less active serotonin transmission) are more prone to having a depression when they experience stressful events than those with LL genotype. Serotonin levels, in a way, make people more resilient to stress.
Biological treatments
1. Drugs
Medications used to treat depression are called antidepressants. These include:
a) MAOIs (monoamine oxidase inhibitors) - have been abandoned for their potentially lethal dietary and drug interactions.
b) Tricyclics - also mostly abandoned due to numerous side effects.
c) SSRIs (selective serotonin re-uptake inhibitors) - most commonly prescribed antidepressants which increase levels of serotonin by inhibiting its re-uptake into the synaptic cell. Examples include Prosac.
2. Light therapy - mostly used for Seasonal depression
3. Electroconvulsive therapy
The therapy was born due to the observation that epileptics do not suffer from depression. EC therapy electrically induces seizures in anaesthetised patients. It was used for the first time in 1938 by Italian psychologist Ugo Cerletti, and has proved to be quite effective in treating depression - however, it is still not known why and how it works.
Below you will find a video about EC; it also shows a woman before and after treatment. Sory for the quality!
Major depression is different from a depression caused by grieving or a negative event, as it does not necessarily occur for a specific reason and tends to reoccur in what is known as Major Depression Episodes (MEDs).
Major depression is a general term for a long-term depression. To be diagnosed, a person should have certain symptoms present most of the days for at least two weeks. These include: anhedonia (loss of interest and pleasure in everyday activities), disturbed sleeping patterns (either insomnia or hypersomnia), disturbed eating pattern (either loss of apetite or overeating), low mood and self esteem, feeling of guilt, loss of energy, motor agitation or retardation, difficulty concentrating, recurrent thoughts of suicide and death.
Dysthymia is often described as a chronic depression. It is characterised by almost constant low mood; the symptoms are . In order to be diagnosed with dysthymia, a person should have a dark, sad mood for most of the days for at least 2 years; in children and adolescents, the mood can be irritable instead, which should last for at least 1 year. In addition, at least two of the following symptoms should be present: disturbed sleeping pattern, change in eating habits, fatigue, low self-esteem.
Depression can be divided into:
a) Melancholic: the most severe type of depression. Its distinctive feature is a lack of mood reactivity: that is, a person's mood does not improve in reaction to positive events. Melancholic depressives may also ruminate over the same thoughts and experiences, and feel excessive guilt. Their depression takes on a life of its own: the more episodes they have, the more autonomous such episodes seem, less likely to be set off by stressful events.
b) Seasonal: depression which occurs at the same time each year, typically in autumn, winter or late spring.
c) Atypical: a condition in which one's mood elevates in response to positive events - something that does not happen in other types of depression. In addition, at least two of the following symptoms are present: weight gain, hypersomnia, heavy sensation in limbs (leaden paralysis) and extremely high interpersonal rejection sensitivity which often cause difficulties in relationships and at work.
d) Psychotic: this is yet another type of severe depression. It is similar to melancholic type, but is also accompanied by hallucinations and/or delusions which reflect the depressed mood and guilt that the patients feel (for example, they might hear a voice telling them they are worthless).
MDEs occur in 17% of population at some point of their lives; in the course of every single year, around 7% of the population are affected by the disorder. Depression is twice as common in women than in men.
MDEs can be subdivided by incident or recurrent. They reoccur in 80% of the patients, which means it is extremely hard to get rid of a depression entirely and to guarantee it would not come back at some point. Studies showed that the probability of an episode to reoccur increases with the number of years passed after the previous episode and the number of previous episodes.
Previously, it was thought that between the episodes patients were simply 'normal'. However, it has been suggested that the episodes leave a 'scar' which makes them more likely to relapse into depressive mood. In 1998, Judd et al. conducted an extensive 12-years study, in which he found that after an incident episode, patients were completely symptom-free only 54% of the weeks. Moreover, those who had suffered from a recurrent episode, were symptom-free mere 37% of the weeks.
Genetic factors
Studies have shown that biological relatives of those diagnosed with depression are three times more likely to have depression than those without family history of depression. According to the findings of twin studies, somewhere between 31%-42% of variance is due to genetic influences. It is actually even higher for more severe, recurrent depressions.
Cognitive factors
People with depression tend to have what is called a negative cognitive triad: they see themselves, environment/people around and future much more negatively than it is supported by facts or than the others see it. They also have distinct cognitive biases. For example, they tend to see the world in black and white, nothing in between; it is frequent mindset that if they are not the very best at something, it is not worth doing at all. Depressives are also prone to rumination: over-thinking and over-analysing their own feelings and emotions.
Environmental factors
Independent life events can contribute to the development of depression. In the Hurricane Katrina study, 2007, it was found that 49.1% of the residents of New Orleans (area most affected by the hurricane) suffered from depression symptoms of varying severity 30 days after the disaster - compared to 26.4% in the areas nearby.
Often depressives put themselves in danger or cause health problems due to poor social judgement, not taking care of themselves (e.g. proper nutrition, hygiene) and loss of motivation to perform at work or school.
Genes + Environment
In 2003, Capri et al. divided the participants by the type of their 5-HT transporter gene (serotonin, aka 'happiness', transporter) into those with SS (short-short), SL (short-long) and LL (long-long) genotypes. He then asked the participants about the number of stressful events that they had in their lives - such as loss of a close person, etc. What he found was that there was a strong relationship between the number of stressful events and the likelihood of getting a depression in those who had an SS genotype. This relationship was weaker in those with the SL genotype and much weaker - with LL one.
This finding demonstrates that those with SS genotype (i.e. less active serotonin transmission) are more prone to having a depression when they experience stressful events than those with LL genotype. Serotonin levels, in a way, make people more resilient to stress.
Biological treatments
1. Drugs
Medications used to treat depression are called antidepressants. These include:
a) MAOIs (monoamine oxidase inhibitors) - have been abandoned for their potentially lethal dietary and drug interactions.
b) Tricyclics - also mostly abandoned due to numerous side effects.
c) SSRIs (selective serotonin re-uptake inhibitors) - most commonly prescribed antidepressants which increase levels of serotonin by inhibiting its re-uptake into the synaptic cell. Examples include Prosac.
2. Light therapy - mostly used for Seasonal depression
3. Electroconvulsive therapy
The therapy was born due to the observation that epileptics do not suffer from depression. EC therapy electrically induces seizures in anaesthetised patients. It was used for the first time in 1938 by Italian psychologist Ugo Cerletti, and has proved to be quite effective in treating depression - however, it is still not known why and how it works.
Below you will find a video about EC; it also shows a woman before and after treatment. Sory for the quality!
4. Psychotherapy
Behavioural therapy focuses on behavioural responses to external environment. It can be quite effective in dealing with depression as it encourages the patients to engage more with the environment
Cognitive-behavioural therapy aims not only to alter the patients' behaviour, but also to enable them to identify and replace distorted thoughts and feelings that they have. It has been proven to be as effective as antidepressants in some cases, and is better in preventing relapses.
Behavioural therapy focuses on behavioural responses to external environment. It can be quite effective in dealing with depression as it encourages the patients to engage more with the environment
Cognitive-behavioural therapy aims not only to alter the patients' behaviour, but also to enable them to identify and replace distorted thoughts and feelings that they have. It has been proven to be as effective as antidepressants in some cases, and is better in preventing relapses.
Bipolar mood disorders
Bipolar disorders include manic episodes alongside the depressive ones. Manias can be described as the 'top of the world', euphoric feeling; in a sense, opposite of depression. Bipolar disorders can be subdivided into two types, I and II. Criteria is as follows:
Bipolar I - presence/history of at least one maniac episode and at least one MDE which can not be accounted for by any drugs or other mental disorders.
Bipolar II - presence/history of at least one MDE alongside hypomania, which is a constantly elevated mood.
Lifelong prevalence of bipolar mood disorders is about 0.5-1.5% of the population worldwide; Type II is more common, and it evolves into Type I in 5-15% of cases. It is equally prevalent in women and men, and is more likely to occur in the those MDE patients who have a creative background (e.g. artists) or history of eccentric behaviour. In about 66% of the cases, manic episodes immediately follow/precede the MDEs. The onset of the disorder is typically 15-25 years old, but sometimes occurs even in children.
Biological Factors
Patients with a bipolar disorder were proven to produce lower levels of serotonin; manic episodes are often associated with increased dopamine (reward and pleasure regulating hormone) and reduced norepinephrine (fight or flight hormone) levels.
It has been found that relatives of those with Bipolar disorder have a 7-8% chance to develop the disorder themselves, and are also at a higher risk of developing a Unipolar disorder. Twins studies showed that a MZ twins have a 60% concordance rate (that is, there is a 60% chance that a MZ twin of a Bipolar patient will develop the disorder).
Treatment
Pharmacological treatment is the only type of treatment available to Bipolar patients. These include antidepressants similar to the ones used in Unipolar cases. Mood stabilisers (most commonly lithium carbonate) are used widely, however it is not yet fully understood how exactly they work. Finally, anticonvulsants (such as valproate) are used to reduce the electric activity in the brain. It is thought that they increase the levels of a natural nerve stabiliser GABA and reduce the levels of glutamate ('excitement' chemical).
Below is a great great description of the disorder by the awesome Stephen Fry who himself is Bipolar. Enjoy!
Bipolar I - presence/history of at least one maniac episode and at least one MDE which can not be accounted for by any drugs or other mental disorders.
Bipolar II - presence/history of at least one MDE alongside hypomania, which is a constantly elevated mood.
Lifelong prevalence of bipolar mood disorders is about 0.5-1.5% of the population worldwide; Type II is more common, and it evolves into Type I in 5-15% of cases. It is equally prevalent in women and men, and is more likely to occur in the those MDE patients who have a creative background (e.g. artists) or history of eccentric behaviour. In about 66% of the cases, manic episodes immediately follow/precede the MDEs. The onset of the disorder is typically 15-25 years old, but sometimes occurs even in children.
Biological Factors
Patients with a bipolar disorder were proven to produce lower levels of serotonin; manic episodes are often associated with increased dopamine (reward and pleasure regulating hormone) and reduced norepinephrine (fight or flight hormone) levels.
It has been found that relatives of those with Bipolar disorder have a 7-8% chance to develop the disorder themselves, and are also at a higher risk of developing a Unipolar disorder. Twins studies showed that a MZ twins have a 60% concordance rate (that is, there is a 60% chance that a MZ twin of a Bipolar patient will develop the disorder).
Treatment
Pharmacological treatment is the only type of treatment available to Bipolar patients. These include antidepressants similar to the ones used in Unipolar cases. Mood stabilisers (most commonly lithium carbonate) are used widely, however it is not yet fully understood how exactly they work. Finally, anticonvulsants (such as valproate) are used to reduce the electric activity in the brain. It is thought that they increase the levels of a natural nerve stabiliser GABA and reduce the levels of glutamate ('excitement' chemical).
Below is a great great description of the disorder by the awesome Stephen Fry who himself is Bipolar. Enjoy!
Suicide
Suicide is the 10th leading cause of death worldwide. It is closely linked to depression, as those with depression are 50 times more likely to commit suicide; 40-60% of those diagnosed with depression do commit suicide during the MDE. Men are about twice as likely to commit suicide as women! Stephen Fry (see above!) confessed he did attempt a suicide couple of times himself =(
Personality Factors
It has been shown that certain personality traits are connected to suicide attempts. Those scoring high on Neuroticism and those scoring low on Openness to Experience are at larger risk to commit a suicide (perhaps they struggle to see alternatives/other points of view?)
Biological Factors
Twin studies showed that MZ twins have 19 times higher concordance rate than DZ twins (Roy et al., 1999); family studies also suggest that suicide is familial. The famous example is the family of Ernest Hamingway, where there were five suicides: Ernest himself, his father, sister, two brothers and granddaughter.
Suicide has also been associated with extremely low serotonin levels.
Prevention
Communication is extremely important in preventing someone from committing a suicide. About 40% of those who commit suicide do talk about their intention, however it is often that people around don't take such intentions seriously. It is important to help a person deal with immediate crisis by providing care and support, especially if the one is known to have depression episodes. It is equally important to keep supporting a person during the recovery, helping them to realise that the depression episode would end.
Personality Factors
It has been shown that certain personality traits are connected to suicide attempts. Those scoring high on Neuroticism and those scoring low on Openness to Experience are at larger risk to commit a suicide (perhaps they struggle to see alternatives/other points of view?)
Biological Factors
Twin studies showed that MZ twins have 19 times higher concordance rate than DZ twins (Roy et al., 1999); family studies also suggest that suicide is familial. The famous example is the family of Ernest Hamingway, where there were five suicides: Ernest himself, his father, sister, two brothers and granddaughter.
Suicide has also been associated with extremely low serotonin levels.
Prevention
Communication is extremely important in preventing someone from committing a suicide. About 40% of those who commit suicide do talk about their intention, however it is often that people around don't take such intentions seriously. It is important to help a person deal with immediate crisis by providing care and support, especially if the one is known to have depression episodes. It is equally important to keep supporting a person during the recovery, helping them to realise that the depression episode would end.