Depression in chronic pain syndrome: types, diagnosis, treatment

The strong link between chronic pain and depression is clear. J. Murray emphasizes that in chronic pain one must first of all look for depression; S. Tyrer (1985) provides statistical data on the occurrence of depressive disorders nature in half of the individuals with chronic pain syndrome. Some authors are even more definite, considering that depression occurs in all cases of chronic pain syndrome, based on the fact that pain is always accompanied by negative emotional experiences and blocks the person's ability to receive joy and satisfaction. The greatest controversy is not the very fact of the coexistence of chronic pain with depression, but the cause-and-effect relationship between them. On the one hand, long-standing pain limits a person's professional and personal capabilities, forces them to abandon their usual life routine, disrupts their life plans, etc. Decreased quality of life can lead to secondary depression. On the other hand, depression can be the root cause of pain or the main mechanism of pain chronicity. Thus, atypical depression can manifest itself under various masks, including under the guise of chronic pain.

Short information about treatment of depression in chronic pain syndrome

In this article, we do not set the task of differentiating the type of depression in all types of chronic pain syndromes. Our goal is to focus the doctor's attention on the undoubted relationship of these two pathological syndromes, their frequent compatibility, to emphasize the need to search for depression in any chronic pain, to teach how to highlight clinical symptoms indicating depressive disorder. All of the above is necessary for full-fledged assistance to the patient, since the depression, regardless of its origin, primary or secondary in relation to chronic pain syndrome, always significantly worsens and changes the clinical picture, aggravates the pain and suffering of the patient, and reduces the patient's quality of life. Depression forms the patient's state of helplessness and complete dependence on the pain syndrome gives rise to a feeling of futility of treatment, and make person feel like they encountered an insurmountable obstacle. Figuratively speaking, a kind of vicious circle is formed between pain and depression, in which one condition aggravates another. Thus, a complete cure of an individual with chronic pain syndrome is impossible without relief of coexisting depressive disorder.

The "kinship" of pain and depression is primarily due to the common links of causes. In both conditions, the deficiency of the serotonergic systems of the brain is determined. The serotonergic theory of depression is currently the leading one, and the significant role of dysfunction of the descending serotonergic analgesic systems of the brain in the formation of chronic pain has also been proven.
In this context, it is important to define what acute and chronic pain is. Acute pain is always a symptom of some kind of organic suffering. Chronic pain, as a rule, is not a symptom, but a disease itself, in which not actual damage to tissues is of decisive importance, but defective perception and other dysfunction of mental processes.

Chronic pain, according to modern medicine, is pain that lasts beyond the normal healing period and is present for at least three months. Nowadays, it is considered an independent disease, which is based on a pathological process in the somatic (physical) sphere and primary or secondary dysfunction of the peripheral and central nervous systems. An integral sign of chronic pain is the formation of emotional and personality disorders; it can only be caused by dysfunction in the mental sphere, i.e. treat idiopathic or psychogenic pain. Psychogenic chronic pain is the most typical and most difficult to diagnose and cure.  Chronic pain syndrome can be observed in the clinical picture of any depression. The manifestations of depression in chronic pain syndrome may be obvious or subtle. Quite often, pain is a "mask" of depression and the symptoms are atypical and hidden behind the dominant pain in the clinical picture.
Individuals with typical manifestations of depression can be quickly sent by the family doctor to psychiatrists. But individuals with atypical, masked depressions are treated for a long time and sometimes to no avail by general practitioners, since it is quite difficult to recognize such depression.

Manifestations of chronic pain syndrome

Chronic pain as a manifestation of depression can be localized in almost any part of the body. Often there is a combination of several localizations. Symptoms can mimic various variants of organic and neurological pathology, therefore, it is necessary to examine the patient in detail. Usually, chronic pain is localized in the head, heart, abdomen, large joints, and back. Examples of chronic pain syndrome include chronic tension headaches, daily chronic headaches, muscle pain.

Chronic pain is often diffuse, monotonous, constant, dull, aching, pulling, and squeezing. Usually, chronic pain is poorly described by the patient and is indefinitely localized. Commonly, the patient shows a fairly large area of pain, which can change from examination to examination.

Pain syndrome is never presented in isolation, but is always combined with complaints of a psychopathological nature. The state of distress, aggravation of psychological conflict, decompensation of emotional and personality disorders always lead to intensification and/or generalization of pain.

Patients with chronic pain and depression have a long history of their illness, they are ineffectual, but persistently turn to doctors of different specialties. They undergo numerous studies that do not confirm either somatic or neurological organic disease. These are patients who, despite many months of examinations by various specialists, do not have a definite diagnosis. Often they are treated symptomatically, trying to stop the pain syndrome with various analgesics. Treatment is ineffective, and patients continue to seek medical attention.

Diagnosing depression is difficult for a non-psychiatric physician. To diagnose depression, you need to know its diagnostic criteria.

Diagnostic signs of depression in chronic pain syndrome are:

Main

- Low or sad mood not depending on different conditions;
- Loss of interest or a sense of pleasure;
- Increased fatigue.

Additional

- Decreased ability to focus;
- Low self-esteem and self-doubt;
- Ideas of guilt and self-deprecation;
- Gloomy, pessimistic vision of the future;
- Suicidal thoughts or actions;
- Sleep disorders;
- Appetite disorders.

To confirm a major depressive episode, the first three major manifestations and at least four additional symptoms must be observed.

A diagnosis of a moderate depressive episode is made in two main and three additional symptoms.

For a mild depressive episode, the presence of two main and two additional symptoms is sufficient.

Moreover, in all three variants of depression, its main manifestations should last at least 2 weeks. In general medical practice, patients with mild and moderate depression are mainly observed. If depressive episodes lasting at least two weeks are repeated at least twice at intervals of several months, then recurrent depressive disorders are diagnosed. Repeated depressive episodes can be triggered by a stressful situation.

Most often, the doctor is faced with atypical depressions. It should be emphasized the frequent occurrence of anxiety disorders in depression, which often come to the fore, obscuring the depressive symptoms themselves. The combination of depression and anxiety reaches 62%. Particularly specific is the combination of anxiety in combination with muscle tension and depression in the chronic pain syndrome.

Special attention should be paid to the fact that individuals with atypical depression may complain exclusively of certain persistent somatic symptoms, the main of which is a constant feeling of fatigue and pain. Increased irritability can often be the main complaint.

In atypical depression, chronic pain is often combined with complaints of other unpleasant, poorly described, and often poorly localized sensations throughout the body - sleep disturbances, appetite, libido, increased fatigue, weakness, decreased performance, constipation, dyspepsia; menstrual irregularities that do not have an organic cause, premenstrual syndrome.

With depression, poor appetite and weight loss can occur, or, on the contrary, increased appetite and, accordingly, an increase in body weight. For typical depressions, a decrease in appetite and body weight is more characteristic; with atypical depressions, the opposite is often observed.

The abundance of complaints, their unusual combination, which does not fit into the clinical picture of any somatic disease, first of all suggests masked depression.

It is specific for depression that all unpleasant symptoms, including painful ones, are more present in the morning than in the evening.
Sleep disturbances in depression can manifest in very different ways: falling asleep disturbances, frequent nocturnal awakenings, sleep dissatisfaction, difficulty waking up, an increase in the duration of night sleep, daytime hypersomnia. The most specific symptom of depression is considered to be early morning awakening, in which the patient constantly wakes up at 4-5 am for no apparent reason and can no longer fall asleep.

Quite often, general practitioners are faced not only with atypical depression, but also with a chronic variant of its course. Previously, this condition was classified as depressive neurosis or neurotic depression, now as dysthymia. According to statistics, up to 5% of the adult population suffers from dysthymia. This disorder is rarely recognized and therefore rarely adequately treated. What are the necessary criteria for a diagnosis of dysthymia?

Dysthymia is a chronic condition that distinguished by bad mood for most of the day for more than half of all days in the past two years. Chronically bad mood should be accompanied by at least two of the following symptoms:

- Lack or, on the contrary, increased appetite,
- Sleep disorders or increased drowsiness,
- Low performance or increased fatigue,
- Low self-esteem,
- Impaired concentration or indecision
- Feeling of hopelessness.

The listed symptoms are often combined with prolonged pain. Dysthymia can last indefinitely, begin at almost any age, often dysthymia is preceded by severe psychotrauma.

When examining patients with chronic pain, to identify depression, special attention should be paid to the patient’s history. Indications of past depressive episodes, mental illness in relatives, alcohol or drug abuse, a severe traumatic situation or emotional stress experienced should alert the doctor. It is necessary to try to identify the connection between the onset and the course of the pain syndrome with the patient's mental experiences. Childhood's anamnesis is also important: the patient's previous painful experience, chronic pain in close relatives, attitude to pain in the family, i.e. features of upbringing that can contribute to the formation of the so-called "pain personality".

When examining a patient, it is imperative to pay attention to the patient's appearance, their posture, demeanor, speech features and behavior, which can help in diagnosing an unconscious or hidden depressive state. Individuals with depression are distinguished by negligence in clothes, preference for gray and dark tones, lack of hairstyles, cosmetics and jewelry in women, scarcity of facial expressions and movements sometimes reminiscent of stiffness, stooped posture, lack of expression and monotony of speech, monosyllabic responses, etc.

Thus, there are various combinations of chronic pain syndrome with various types of depression.

The doctor needs to pay special attention to depression in chronic pain since depression coexisting with pain significantly aggravates and modifies the clinical picture of the disease.

Therapy of depression in chronic pain syndrome

Regardless of whether depression is primary or secondary in relation to chronic pain, it must be treated using psychotherapeutic and psychopharmacological methods.

When chronic pain syndrome is accompanied by depression, antidepressants occupy the first place in therapy, which have not only an antidepressant but also an actual analgesic effect.

The effectiveness of antidepressants in the therapy of chronic pain syndromes reaches 75%. But it depends on the share of depression in the occurrence of chronic pain.

The painkiller action of antidepressants is due to:

- The treatment of depression (this mechanism is especially significant if the pain syndrome was a mask of depression, i.e. in primary depressions. But in secondary depression occurring as a result of pain, the reduction of depression also leads to a weakening of the pain syndrome);
- The potentiation of the action of both exogenous and endogenous analgesic substances, mainly opioid peptides;
- The stimulation of serotonergic systems of the brain.

Researches prove that the painkiller effect rendered by antidepressants, for instance, Anafranil, a tricyclic antidepressant, is observed even in the lower dosages and in a shorter period of time than for depressive symptoms treatment. When the symptoms are managed by the drugs, it is possible to add psychotherapy to consolidate the results.

Post by: Elizabeth Agrer, clinical pshychiatrist, Copenhagen, Denmark