Epilepsy Ontario :: Depression and Epilepsy (article)

Depression and Epilepsy

by Jennifer Li

Definition

Depression – sometimes referred to as Major Depressive Disorder – is defined as a psychiatric disorder characterized by feelings of extreme sadness, the inability to concentrate, insomnia, loss of appetite, anhedonia, guilt, helplessness and hopelessness, and thoughts of death.

Although there is not a definite boundary between the two, depression and sadness are not the same. Sadness usually lasts one or two days, while depression is a prolonged sadness that can lead to deterioration and impaired functioning in many aspects of one's life.

Brief History

Depression was first distinguished from schizophrenia in 1895 by the German psychiatrist Emil Kraepelin, when he recognized alternating periods of low and elevated mood in some patients (2). He also developed the current classification of depression. In 1917, Sigmund Freud, in his work called Mourning and Melancholia, described depression as "anger turned upon the self" (2). In the first half of the 20th century, while Freud's psychodynamic theories dominated most beliefs, depression was understood as a disorder of the mind; however, as more studies and theories came about, depression became a "disorder of the brain".

Since Freud's psychoanalysis, many other classes of therapies began to emerge. Albert Ellis, who was a trained practitioner of Freudian psychoanalysis, upon suggesting the superficial and unscientific nature of Freud's technique, invented Rational-Emotive Therapy. It is his non-medical approach, which focuses on altering behaviour by confronting patients with their irrational beliefs and persuading them to adopt rational ones (2). In 1976, Aaron Beck – another trained psychoanalyst – published Cognitive Therapy and Emotional Disorders, in which he employed a cognitive approach to halt recurrent negative thoughts that lead to depression (2).

Medical treatment of depression has also begun to take a significant role in recent decades. In the early 1950s, several clinicians observed that iproniazid, a drug developed for tuberculosis, can elevate mood in some patients. This later led to a class of antidepressants called the monoamine oxidase (MAO) inhibitors (2). After several years of widespread use, they were found to have major side effects. In 1958, Roland Kuhn tested the tricyclic compound imipramine in psychiatric patients (2). It appears that the mechanism of the tricyclics blocks the reuptake of two neurotransmitters – norepinephrine and serotonin. In the 1980s, there came a second wave of antidepressants: another group of drugs, called selective serotonin reuptake inhibitors (SSRIs)(2). The SSRIs are known to have a quicker effect on the symptoms of depression and produce fewer side effects. In 1987, the U.S. company Eli Lilly developed fluoxetine (Prozac), which is an SSRI antidepressant and was proven to be the most successful psychiatric drug in history (2). Newer drugs, including dopamine reuptake inhibitors (bupropion) and alpha-2 receptor antagonists (mirtazapine), became available in the 1990s (2).

Prevalence

Age
Males
% of age group with depression
Females
% of age group with depression

12 – 17 years
41,050
--
93,423
8.3

18 – 24 years
79,408
6.6
127,695
10.8

25 – 44 years
156,139
3.5
404,229
8.6

45 – 64 years
94,546
3.5
183,333
6.3

65 and over
22,309
--
53,475
3.1

-- amount too small to be expressed

Source: Statistics Canada,National Population Health Survey, 1995.
http://www.canoe.ca/HealthReference/statscan_4.html

In Canada, the prevalence of depression is between 5% and 10%. In some cities, prevalence of between 10% and 15% has been reported (8).
Depression is almost twice as prevalent in women as in men (11).
20% of patients with major depression also exhibit panic disorder (6).

Cause

There are two major groups of contributors to depression, one being the emotional/psychosocial factors, and the other being the biological factors.

Psychologically, there are three things that trigger depression: a traumatic life event; a series of disappointments and problems over a long period of time; and chronic depression (dysthymic disorder) reaching a crisis (1). For instance, some common triggers of depression are bereavement, divorce, relationship difficulties, coping with long-term physical illnesses, and work pressures (1). Often these factors may lead the individual to feel a sense of failure or a loss of self-confidence, which in turn could gradually initiate an onset of depression.

The following table lists some common risk factors for depression (1):

Psychosocial	Illness	Medicines	Other
Change of job Relationships Moving house Bereavement Unemployment Financial worries Divorce/separation	Flu Infectious diseases Stroke Cancer Diabetes MS	Anti-hypertensives H2 Blockers Corticosteroids	Menopause Seasonal changes Drug abuse Alcohol abuse

In many other cases, the cause of depression may be biological/chemical. Biological factors may include changes in brain chemistry, hormonal effects, kindling, genetics, medical/neurological disorders and medication (11). Many studies suggest that depression may be influenced by low levels of brain norepinephrine, serotonin or dopamine, hence many medical treatments for depression focus on preventing the reuptake of these neurotransmitters. Genetics also play an important role: children of depressed parents are at a 10-15% risk for depression (11).

Some researchers have found a possible link between damage to the frontal and temporal lobes of the brain and depression. However, many people with brain damage do not become depressed (10).

Moreover, there are some specific causes of depression in individuals with epilepsy (14):

Social stigmatization
Discrimination
Vocational difficulties
Restrictions in activities of daily life
Abnormalities in the synthesis and release of noradrenaline, dopamine, 5-hydroxytryptamine, GABA and corticotrophin-releasing hormone, often due to the combination of a genetic predisposition and psychosocial stressors
Polypharmacy
Anticonvulsant therapy (e.g. Phenobarbital, phenytoin, vigabatrin and lamotrigine)

Common Symptoms

According to the DSM-IV, Major Depressive Disorder causes the following mood symptoms (12):

Abnormal depressed mood;
Sadness is usually a normal reaction to loss. However, in major Depressive Disorder, sadness is abnormal because it:
- Persists continuously for at least 2 weeks.
- Causes marked functional impairment.
- Causes disabling physical symptoms (e.g., disturbances in sleep, appetite, weight, energy, and psychomotor activity).
- Causes disabling psychological symptoms (e.g., apathy, morbid preoccupation with worthlessness, suicidal ideation, or psychotic symptoms).
The sadness in this disorder is often described as depressed, hopeless, discouraged, "down in the dumps," "blah," or empty feelings. The sadness may be denied at first. Many complain of bodily aches and pains, rather than admitting to their true feelings of sadness.
Abnormal loss of interest and pleasure mood:
- The loss of interest and pleasure in this disorder is a reduced capacity to experience pleasure which in its most extreme form is called anhedonia.
- The resulting lack of motivation can be quite crippling.
Abnormal irritable mood:
- This disorder may appear primarily with irritable, rather than depressed or apathetic mood. This is not officially recognized for adults, but it is recognized for children and adolescents.
- Unfortunately, irritable depressed individuals often alienate their loved ones with their cranky mood and constant criticism.

According to the DSM-IV, Major Depressive Disorder causes the following physical symptoms (12):

Abnormal appetite: Most depressed patients experience loss of appetite and weight loss. The opposite, excessive eating and weight gain, occurs in a minority of depressed patients. Changes in weight can be significant.
Abnormal sleep: Most depressed patients experience difficulty falling asleep, frequent awakenings during the night or very early in the morning. The opposite, excessive sleeping, occurs in a minority of depressed patients.
Fatigue or loss of energy: Profound fatigue and lack of energy is usually prominent and disabling.
Agitation or slowing: Psychomotor retardation (an actual physical slowing of speech, movement and thinking) or psychomotor agitation (observable pacing and physical restlessness) often are present in severe Major Depressive Disorder.

According to the DSM-IV, Major Depressive Disorder causes the following cognitive symptoms (12):

Abnormal self-reproach or inappropriate guilt:
- This disorder usually causes a marked lowering of self-esteem and self-confidence with increased thoughts of pessimism, hopelessness, and helplessness. In the extreme, the person may feel excessively and unreasonably guilty.
- The "negative thinking" caused by depression can become extremely dangerous as it can eventually lead to self-defeating or suicidal behaviour.
Abnormal poor concentration or indecisiveness:
- Poor concentration is often an early symptom of this disorder. The depressed person quickly becomes mentally fatigued when asked to read, study, or solve complicated problems.
- Marked forgetfulness often accompanies this disorder. As it worsens, this memory loss can be easily mistaken for early senility (dementia).
Abnormal morbid thoughts of death (not just fear of dying) or suicide:
- The symptom most highly correlated with suicidal behaviour in depression is hopelessness.

Seizures

It is reported that 42% of the epileptic population develops depression, making it the most prevalent psychiatric illness associated with epilepsy. The following paragraph is quoted from an article written by Dr. Alan Lowe, MD, FRCPC, from Department of Psychiatry of the Toronto Hospital, Western Division.

The impact of depression on people with epilepsy is significant. In addition to impairing daily functioning, it can lead to greater seizure frequency and less seizure control through sleep deprivation and a failure to comply with medication or due to its role as an emotional stressor. Depressed people may abuse their medication, which can be potentially lethal in high doses and in combination with alcohol and street drugs. (14)

Depression can occur during the "prodromal" stage – changes in mood or behaviour in the period before a seizure occurs – or at the "postictal" state – brief depression and confusion following a seizure. Symptoms of depression may also be triggered by social problems related to a diagnosis of epilepsy or to an increase in the number of seizures being experienced (10).

Depression can also come from the side effects of anticonvulsant drugs. For instance, Phenobarbital has a 5% risk of causing depression, followed by Vigabatrin, lamotrigine and Phenytoin, possibly due to folate deficiency (11). However, certain drugs, such as Carbamazepine and valproic acid, can, in fact, help stabilize and improve mood, and are frequently used in psychiatry to treat unipolar and bipolar depression (11).

Diagnosis

The DSM-IV Diagnostic Criteria for Major Depressive Disorder is as follows (12):

A. At least one of the following three abnormal moods which significantly interfered with the person's life:

B. At least five of the following symptoms have been present during the same 2 week depressed period.

C. The symptoms are not due to a mood-incongruent psychosis.
D. There has never been a manic episode, a mixed episode, or a hypomanic episode.
E. The symptoms are not due to physical illness, alcohol, medication, or street drugs.
F. The symptoms are not due to normal bereavement.

Careful diagnosis usually involves clinical interviews and mental status examinations. Generally, open-ended questions regarding the patient's level of functioning and motivation are asked primarily. The acronym SIGECAPS is often used to cover a whole range of symptoms that could suggest depression in a patient (6):

Sleep disturbance
Interest/pleasure reduction
Guilt feelings or thoughts of worthlessness
Energy changes/fatigue
Concentration/attention impairment
Appetite/weight changes
Psychomotor disturbances
Suicidal thoughts

During a diagnosis, many screening tools could be used to identify depression or the risk of depression. Although no single test is universally conducted, the most common ones are listed below (6):

Beck's Depression Inventory – with a total of 21 questions, each question is rated on a scale of 0 to 3 (where zero represents normality and 3 represents severe disturbance) (4). This test reflects attitudes that are often exhibited in depressed people.
The Harvard National Depression Screening Scale (HANDS) – a 10-item screening scale that is simple and quick to administer and score.
The Inventory to Diagnose Depression (IDD) – a self-rating scale used in diagnosing major depressive disorder. It takes a limited amount of time and has a six-grade reading level.
The Mood and Feelings Questionnaire (MFQ) – this is a self-rating scale that's targeted at children and adolescents. A different version of the questionnaire can be given to parents, who might provide important information about their child or adolescent.
The PHQ-9 Patient Questionnaire – a questionnaire that can be completed by the patient before, during or after an office visit. This questionnaire can be used to detect or qualify the severity of depressive disorder. It may also help to administer the effectiveness of treatment on a patient.
The Primary Care Evaluation of Mental disorders (PRIME-MD) – a two-stage diagnostic system that screens for multiple disorders, including depression, GAD, panic disorder, alcohol abuse, somatoform disorders and eating disorders. It includes a patient questionnaire and a guided interview for the physician.

In a diagnosis of depressive disorder, it is crucial to be distinctive between major depressive disorder, dysthymia, and manic depression, because the treatment and therapy for each is quite different (6).

Classification

The classification of depressive disorders is based on the intensity of the symptoms, the duration of the symptoms, and if possible, the specific cause of the symptoms (13).

Major Depression
This is the most severe type of depression, where most of the depressive symptoms are present with relatively high intensity. The cause of major depression could be a single traumatic experience in life, or a series of personal disappointments and problems. Sometimes, a person begins with a mild form of depression, which drastically increases in severity when a life crisis strikes.

It isn't rare for major depression to occur only once and never again in a person's life, usually with the help of treatment. This would be a single episode depression (13). However, in many cases episodes of depression do recur, usually after several years without depression. This is called a recurrent depression.

Dysthymic Disorder
This is a rather mild form of depression that lasts for a longer period of time, usually for at least 2 years. It is characterized by low energy, sleep or appetite disturbances and low self-esteem (13). Usually, people with dysthymic depression can still manage with their daily functioning, but with certain levels of distress caused by symptoms of dysthymia.

It is important to note that if a person has a chronic medical condition that appears to be the cause for the depression, then the correct diagnosis should be a Mood Disorder due to a general Medical Condition (13).

Unspecified Depression
Whenever a depressive disorder cannot be placed in any other categories due to its "unqualified" symptoms, it is said to be depression, not otherwise specified. An unspecified depression typically has mild to moderate symptoms, which last longer than 6 months (in order to be excluded from adjustment disorder) but shorter than 2 years (in order to be excluded from dysthymic disorder).

Adjustment Disorder
Adjustment disorder is used to categorize mild to moderate depressive symptoms following a psychosocial stressor in a person's life; therefore it is also called a "reactive depression" (13). It is often considered a last-resort category because its diagnostic criteria are similar to that of a major depression.

If the symptoms of depression continue for more than 6 months, a diagnosis of depression, not otherwise specified, would be more appropriate. However, in cases where stressful events continue for a long time, a diagnosis of adjustment disorder would still be valid after 6 months (13).

Bipolar Depression
Bipolar depression, also called Manic-Depressive Disorder, consists of cycles of euphoria and depression. It can be considered a chronic condition because an untreated person who experiences a manic episode will likely experience more in the future (13). Moreover, every person develops his unique pattern of manic and depressive cycles, which can often be identified and be used to predict future occurrence of episodes.

Research suggests that bipolar disorder has a genetic basis. It typically makes an initial appearance in adolescence, or early adulthood, and continues throughout life. Unfortunately, it is often unrecognized as a psychological problem due to its episodic nature (13).

References:

http://www.medify.com/pat_info/depression/htm/emotionalcauses.html

http://www.hopkinsafter50.com/html/silos/depression/haARTICLE_history.html

http://www.eqi.org.au/newsletter/photosensitive.html

http://www.abpi.org.uk/publications/publication_details/targetDepression/section3.asp

http://www.aafp.org/afp/monograph/200002/index.html

http://www.ispor.org/meetings/va0502/presentations/sesion2/PMHIO.pdf

http://www.epilepsy.org.uk/info/depression.html

http://www.epilepsytoronto.org/people/eaupdate/vol9-4.html

http://www.psychologynet.org/major.html

http://www.psychologyinfo.com/depression/depression_types.html