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REVIEW ARTICLE
Year : 2013  |  Volume : 6  |  Issue : 1  |  Page : 14-18  

Psychogenic dyspnea


Department of Pulmonary Medicine, Padmashree Dr. D. Y. Patil Medical College, Hospital & Research Centre, Dr. D. Y. Patil Vidyapeeth, Pimpri, Pune, India

Date of Web Publication14-Mar-2013

Correspondence Address:
Tushar R Sahasrabudhe
Department of Pulmonary Medicine, Padmashree Dr. D. Y. Patil Medical College, Hospital & Research Centre, Dr. D. Y. Patil Vidyapeeth, Pimpri, Pune
India
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/0975-2870.108627

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  Abstract 

Dyspnea is a very common presenting complaint of a patient. Though commonly due to an organic disease, dyspnea can be a manifestation of underlying anxiety disorder. Three typical patterns of psychogenic dyspnea, viz. panic attack, psychogenic hyperventilation, and compulsive sighing, have been reviewed in this article. The article also comments on the diagnostic features and treatment of these patterns. The overlap with organic causes of dyspnea such as bronchial asthma and Chronic Obstructive Pulmonary Disease (COPD) has also been discussed. For literature review, a Medline and Pubmed search was conducted using appropriate keywords. Articles were also identified from the authors' own knowledge of the literature as well as reference lists in articles retrieved.

Keywords: Dyspnea, hyperventilation, panic, psychogenic, sighing


How to cite this article:
Sahasrabudhe TR. Psychogenic dyspnea. Med J DY Patil Univ 2013;6:14-8

How to cite this URL:
Sahasrabudhe TR. Psychogenic dyspnea. Med J DY Patil Univ [serial online] 2013 [cited 2017 May 23];6:14-8. Available from: http://www.mjdrdypu.org/text.asp?2013/6/1/14/108627


  Introduction Top


Dyspnea has been defined as "an abnormal and uncomfortable awareness of one's own breathing in the context of what is normal for a person according to his or her level of fitness and exertion threshold for breathlessness." [1] It has also been described as a subjective sensation of "air hunger." [2] It may be noted that the word "awareness" is subjective, and therefore dyspnea is also subjective. It is a clinician's common experience that no two individuals with same reduction in lung function will have the same level of dyspnea. Rather, the feeling of dyspnea in the same individual changes at different points of time and in different situations. It is the moment when the "conscious mind" takes cognizance of the respiratory discomfort that the dyspnea is noticed. [3]

This fact can be used to therapeutic advantage, as dyspnea can be treated as a different symptom and the conscious mind can be trained to feel less dyspnea, without actually improving the underlying respiratory condition. [4],[5] However, dyspnea is a very common psychosomatic symptom as well.

The purpose of this review is to explore the spectrum of presentations of dyspnea that are either entirely or partly due to psychological disturbance, with a focus on their clinical features and correct diagnosis. The management has been only briefly touched upon.


  Literature Review Top


A Medline and Pubmed search was conducted using the following keywords: "psychogenic dyspnoea," "asthma," "sighing," "anxiety," "hyperventilation," etc. Appropriate articles were also identified from the author's own knowledge of the literature as well as reference lists in articles retrieved.


  Current Evidence Review and Discussion Top


It is more common for the psychogenic factors to increase the perception of dyspnea due to an underlying physical disease. This is an important area of therapeutic intervention in people suffering from chronic respiratory disorders such as COPD. [6] However, psychogenic stress can also be a potent trigger for some diseases that can cause dyspnea, for example, bronchial asthma. [7],[8] The symptoms of anxiety and true pulmonary disease such as asthma show considerable overlap. [9] Dyspnea can also be a sole manifestation of emotional stress and some interesting patterns of clinical presentation are observed as described in this review. Also, dyspnea per se triggers significant anxiety and fear in the patients with underlying cardiopulmonary disease. Thus, it can be said that the anxiety can reflect underlying cardiopulmonary disease or a dyspnea may reflect an underlying anxiety disorder or both can co-exist.


  Anxious breathing/panic attack Top


This is an irregular breathing pattern with shallow rapid breaths. The breathing is usually thoracic instead of typical quiet abdominal breathing. It is associated with transient giddiness, palpitations, and tremors. [10] This is usually a manifestation of acute anxiety. The presentation can be of rapid onset or gradual onset. The DSM-IV-TR describes these under panic disorder and anxiety disorder differently. [11] Panic disorder with non-respiratory subtype has also been described. The respiratory subtype has peculiar characteristics, such as the increased sensitivity to CO2, and these patients have higher familial history of panic disorder. [12] The mechanism behind this kind of sudden dyspnea is rapid surge of adrenaline getting pumped into the blood stream. This is a form of "fight or flight response" that nature has designed to provide extra oxygen and blood pressure to face the acute crisis. Usually, this is a short-lasting phenomenon and is experienced by most of us once in a while, especially during our practical exams, especially viva.

However, this response may get prolonged enough to compel the patient to seek a doctor's opinion. It is usually expressed by the patient as heaviness in chest and inability to speak complete sentences in a single breath. Panic symptoms have been classified into three categories. They are summarized in [Table 1]. [13],[14]
Table 1: Features of panic attack

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Examination reveals tachycardia, tachypnea, irregular respiration, and increased blood pressure. A dyspnea-fear theory has been postulated which suggests that the fear of dyspnea may additionally precipitate actual airway obstruction in patients of panic disorder. [15] This and the false-suffocation alarm theory have been closely criticized. [16],[17] Angina is the closest differential to be considered and an ECG can usually rule out an ischemic heart event. A history of acute emotional stress can usually be traced.

In anxiety attacks, there are stressors that build over time and lead to less severe reactions that can last for weeks or months, whereas panic attacks have a sudden onset of symptoms that lasts shorter with more intense symptoms. These are usually caused by a sudden or acute stress. Panic disorder is an anxiety disorder characterized by recurring severe panic attacks. It may also include significant behavioral changes lasting at least a month and of ongoing worry about the implications or concern about having other attacks. The latter are called anticipatory attacks. [11]

The DSM-IV-TR diagnostic criteria for panic disorder require unexpected, recurrent panic attacks, followed in at least one instance by at least a month of a significant and related behavior change, a persistent concern of more attacks, or a worry about the attack's consequences. There are two types, one with and another without agoraphobia. Diagnosis is established by ruling out attacks due to a drug or medical condition, or by panic attacks that are better accounted for by other mental disorders. [11]

The treatment includes reassurance and tranquilizers. Beta blockers can effectively block most of the symptoms and the attack can be relieved quickly. Benzodiazepines are commonly used to relieve the attack although the World Federation of Societies of Biological Psychiatry suggests against their use as a first-line treatment option. [18]

For long-term treatment, antidepressants, especially Selective Serotonin Reuptake Inhibitors (SSRIs), are commonly prescribed. Although these medications are described as antidepressants, they have anti-anxiety properties partly due to their sedative effects. However, SSRIs have been also known to exacerbate symptoms in panic disorder patients, especially in the beginning of treatment, and are also known to produce withdrawal symptoms which include rebound anxiety and panic attacks. Co-morbid depression has been cited as imparting the worst course, leading to chronic, disabling illness. [19],[20]


  Psychogenic hyperventilation syndrome Top


This is a very characteristic and typical syndrome. Once witnessed, it is easy for a clinician to recognize this pattern in future. A classical case can be described as follows.

A young lady presents to the clinician with complaints of severe breathlessness. The onset is sudden and starts with dyspnea. It is accompanied by giddiness, ringing in ears, severe fatigue, and finger spasms. On examination, the muscles are flaccid, making the lady even difficult to sit or stand properly, fingers show typical tetanic type carpopedal spasms, and the respiration is deep, rapid, and forceful. The cyanosis is typically absent, oxygen saturation is normal, and there is only mild or no tachycardia. Respiratory and cardiovascular system examination is usually normal. [21]

The pathophysiology behind this syndrome is very interesting. The syndrome, triggered usually by an acute emotional stress, is an attention-seeking behavior. Strange inputs from subconscious mind stimulate the respiratory center. This leads to excess hyperventilation by the person. Hyperventilation results in excess washout of carbon dioxide (CO 2 ) from the blood, thus inducing acute respiratory alkalosis. [22] This is responsible for all the neurological manifestations of the syndrome. Alkalosis pushes the calcium from blood into the cells, thus inducing acute hypocalcemia resulting in carpopedal spasms of the fingers. [23]

It is important to remember that acute hyperventilation due to any cause can trigger the same metabolic cascade. Hence, it is important to rule out other causes of acute hyperventilation such as brain stem stroke, pulmonary embolism, acute myocardial infarction, foreign body aspiration, tension pneumothorax, carbon monoxide poisoning, etc. [24],[25] Fortunately, most of these can be ruled out on correct history and examination only and investigations may not be needed. In these patients, lactate levels are frequently elevated. The exact mechanism is not known because high lactates are usually associated with acidosis and not alkalosis. This therefore should not be regarded as an adverse sign or as a pointer toward diagnosis other than psychogenic hyperventilation. [26],[27] It is important to note that the patient of psychogenic hyperventilation syndrome is never hypoxic, and therefore presence of cyanosis or significant tachycardia always points to an organic disease. Sometimes, the typical symptomatology can also be misdiagnosed as a conversion reaction. [28] The diagnostic criteria are summarized in [Table 2].
Table 2: Criteria for diagnosing psychogenic hyperventilation

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DSM-IV-TR (Diagnostic and Statistical Manual of Mental Disorders: 4 th Text revision) classifies psychogenic hyperventilation syndrome under somatoform disorders. A somatoform disorder is a mental disorder characterized by physical symptoms that suggest physical illness or injury, but symptoms cannot be explained fully by a general medical condition, direct effect of a substance, or are attributable to another mental disorder. In somatoform disorder, medical test results are either normal or do not explain the person's symptoms. Patients with this disorder often become worried about their health because the doctors are unable to find a cause for their health problems. This causes severe stress, due to preoccupations with the disorder that portrays an exaggerated belief about the severity of the disorder. DSM-IV-TR also requires that the symptoms are not intentionally produced and are not malingered. [29]

Once the diagnosis is made, the treatment can give a dramatic response. It is called as "paper bag breathing." The patient is firmly instructed to get up in bed. It is important to send the relatives out of the sight of the patient. This is because the phenomenon is usually an attention-seeking one and by sending away the relatives, an important motive for the hyperventilation syndrome is removed. The patient is then made to breathe in a paper bag. This leads to re-inhalation of the exhaled CO 2 . This increases the CO 2 levels in the blood again and reverses the whole cascade within minutes. [30] Some physicians have also advocated administering calcium gluconate injection to relieve the carpopedal spasms. However, this may not be necessary as the patient usually does not have calcium deficiency but has only intracellular shift of calcium.

Thorough counseling of the patient and relatives is essential and improvement in social and family environment is advised. Cognitive behavioral therapy (CBT) is the best established treatment for a variety of somatoform disorders including psychogenic dyspnea. [31] Many personality traits and morbid conditions have been linked with this syndrome. [32],[33] Antidepressants and adjuvant therapies such as acupuncture have also been tried. [34] The use of antidepressants is, however, not conclusively established.


  Compulsive sighing Top


This again is a characteristic presentation. The patient usually complains of inadequate depth of breath and tends to sigh frequently. "Sighing" refers to taking a deep breath, much larger than the tidal volume. Every individual normally sighs involuntarily 6-8 times per hour. This helps keep open the alveoli that are not frequently used during quiet breathing. Occasional emotional sigh is very common, usually described as "sigh of relief" or "sigh of sorrow." However, when it is recurrent and troublesome, it qualifies for the diagnosis of "compulsive sighing" or "sigh syndrome." The diagnostic criteria for compulsive sighing are summarized in [Table 3]. [35]
Table 3: Criteria for diagnosing compulsive sighing

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The diagnosis is clinical. [36] No investigations may be needed though an X-ray chest and ECG is frequently done to rule out any significant heart or lung pathology. The spirometry is usually normal. Interestingly, history of acute stress is usually not evident in such cases. The cause is usually an old unresolved negative emotion that has been suppressed. Sody et al. observed that 32.5% patients had a significant traumatic event that preceded the onset of symptoms, 25% had previous anxiety or somatoform-related disorders, and the sigh syndrome episode repeated itself after an initial episode in 57.5% patients. [35] Attempts to correlate incidence of sighing with particular personality traits have been unsuccessful. [37]

As per the ICD-10 (International Statistical Classification of Diseases and Related Health Problems, for a definite diagnosis, obsessional symptoms or compulsive acts, or both, must be present on most days for at least two successive weeks and be a source of distress or interference with activities. The obsessional symptoms should have the following characteristics: [38]

  1. They must be recognized as the individual's own thoughts or impulses.
  2. There must be at least one thought or act that is still resisted unsuccessfully, even though others may be present which the sufferer no longer resists.
  3. The thought of carrying out the act must not in itself be pleasurable (simple relief of tension or anxiety is not regarded as pleasure in this sense).
  4. The thoughts, images, or impulses must be unpleasantly repetitive.
The treatment consists of mild antidepressants such as SSRIs and deep breathing exercises. Relaxation techniques such as Yoganidra are very useful for early resolution of the episode. The patient is motivated to remember old emotional traumas or unresolved conflicts and face them one by one. [39] Exposure and ritual prevention, a very useful technique in Obsessive Compulsive Disorder (OCD), is not very useful alone in compulsive sighing. [40]

Overlap syndromes

Emotional excitement is a known trigger for a genuine asthma attack. It is a proven observation that asthma in children is more common before exams (negative excitement) and before birthdays (positive excitement). The pathophysiology is uncertain.

There is a considerable overlap between asthma, panic attacks, and hyperventilation syndrome, and they all can co-exist. Attempts to differentiate them only on the basis of spirometry may not be sufficient. [41],[42] Combination of self-management program and relaxation techniques can be useful adjuncts to standard asthma therapy. [43]


  Conclusion Top


As most cases of dyspnea are likely to present initially to family physicians, pediatricians, pulmonologists, and cardiologists, rather than psychiatrists, it is essential for these physicians to be aware of this spectrum of psychosomatic dyspnea so that timely diagnosis can be made without unnecessary investigations and correct treatment can be offered. Careful history and thorough clinical examination is of utmost importance.

Features which differentiate psychogenic breathing symptoms from organic ones can be summarized as follows:

  1. Absence of nocturnal symptoms
  2. Presence of underlying emotional traumatic event
  3. Absence of typical environmental triggers
  4. Symptoms more prominent at rest
  5. Normal diagnostic test results during symptoms
It is always appropriate to refer these patients for specific management including psychotherapy. This would ensure that the recurrences are avoided.

 
  References Top

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    Tables

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  In this article
Abstract
Introduction
Literature Review
Current Evidence...
Anxious breathin...
Psychogenic hype...
Compulsive sighing
Conclusion
References
Article Tables

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