Panic Disorder

Definition/Description

Panic disorder is a type of anxiety disorder that is characterized by repeated, spontaneous and unexpected panic attacks.[1][2] Feelings of terror will develop for no apparent reason and may trigger severe physical reactions combined with major changes in behavior or persistent anxiety over having further attacks.[3] The ongoing fear of having another panic attack can affect daily functioning and general quality of life.[4] It can cause the person to avoid places and situations where an attack has occurred or where they believe an attack will occur.

Upon diagnosis of panic disorder the psychiatrist must also determine whether agoraphobia is present or not. Agoraphobia refers to a irrational fear for places or situations where help is not easily accessed, escape can be difficult, or where a panic attack is likely to occur.[1][5][6] Those with agoraphobia might avoid crowded environments such as grocery stores, restaurants, malls, churches, and public transportation. This avoidance behavior may lead to the person refusing to travel outside their home or requiring to be accompanied by a friend or family member.[6] People with agoraphobia are aware that these fears are irrational.[1]

Clinically relevant neuro-anatomy

  • Amygdala:
    • Situated in the frontal lobe and responsible for the coordination of behavior and response to fear.
  • Locus coeruleus:
    • Primary noradrenaline nucleus in the brain
    • Plays a role in the processing of fear-related stimuli
  • Thalamus:
    • Redirects sensory stimuli to the sensory cortex and amygdala
  • Hippocampus:
    • Part of the neural network responsible for conditioning and contextual response
  • Hypothalamus:
    • Plays a role in the sympathic activation and neuro-endocrine response

[1]

Epidemiology/Etiology

Epidemiology

The lifetime prevalence of panic disorder is 1.6-4% while the onset of age is 20-29 years.[1][7] Panic disorder can be classified as with or without agoraphobia. Therefore, prevalence rates for the two classifications of the disorder exist as well. According to the National Comorbidity Study, the lifetime prevalence without agoraphobia is 3.5%, while the lifetime prevalence with agoraphobia is 5.3%.[6] Panic disorder affects about 2.4 million adult Americans and is twice as common in females.[1] Symptoms usually begin before age 25, but may occur in the mid 30s as well.[2] The onset of panic disorder can also occur prior to puberty, however, it is uncommon based on the very low prevalence (0.5-1%) of the general pediatric population. Although panic disorder may occur in children, it is often not diagnosed until they are older. If panic disorder happens to appear prior to adulthood it is more likely to be seen in adolescent females. Symptoms of panic disorder that are evident in childhood and adolescence can often lead to future psychiatric disorders.

Etiology

The exact cause of panic disorder has yet to be determined, however, several factors are thought to play a role in the development of this disorder. Family history, brain abnormalities, substance abuse and stress are among the factors that trigger panic attacks and furthermore, panic disorder.[8]

Genetics

Studies have shown that the cause is strongly correlated with the familial component. A literature review of several studies determined that individuals who have first-degree relatives with panic disorder are up to 20 times more likely to develop the disorder than control subjects.[8] Family studies of twins also support strong correlation of panic disorder and genetics. It is indicated that identical twins have a significantly higher matching rate for panic disorder than fraternal twins. Studies further suggest that if an identical twin has panic disorder 40% of the time the other twin will develop the disorder.[1][2]

Autonomic nervous system

Biological theories suggest that defects in an individual’s autonomic nervous system are potential causes for the development of panic disorder. Such defects in the autonomic nervous system result in hypersensitivity, increased arousal and chemical imbalance which can lead to panic attacks.[9] Other studies reveal that abnormalities in the brain contribute to the development of panic disorder. Evidence from imaging studies have shown abnormalities in cerebral blood flow and cerebral metabolism. Furthermore, researchers believe that the brain’s limbic system, specifically the amygdala, is responsible for the misinterpretation of the significance of bodily sensations. As the amygdala misinterprets a situation, the parabrachial nucleus is stimulated causing an increase in respiratory rate while also causing an increase in norephinephrine release resulting in an increase in blood pressure and heart rate.[8]

Substance abuse

Research shows a strong relationship between panic disorder and drug and alcohol abuse. It has been proposed that those with panic disorder use smoking and alcohol as a means of self-medication. However, other models suggest that substance abuse can exacerbate symptoms of panic disorder. One study indicates that smoking is three times more prevalent and harmful and that hazardous alcohol abuse is twice as prevalent in individuals with a history of panic attacks.[10]

Psychological factors

Other theories suggest that panic disorder is related to psychological factors. Individuals with panic disorder commonly have a history of anxiety sensitivity in which they perceive bodily sensations to result in severe and life-threatening consequences.[11] An individual is likely to develop panic disorder if he/she has a history of physical or sexual abuse. Other potential causes include physical illness, significant life transitions, or severe stress such as the death of a family member.[12]

Characteristics/Clinical presentation

According to the Diagnostic and Statistical Manual of Mental Disorders, 4th Edition (DSM-IV), diagnostic criteria includes: “recurrent unexpected panic attacks” that are followed by 1 month or more of “persistent concern about having additional attacks,” “worry about the implications of the attack or its consequences,” or “significant change in behavior related to attacks.”[7]

Signs and symptoms

Panic disorder is characterized by many somatic and cognitive symptoms. The following are characteristics of a panic attack which can occur at any time and generally last around 10 minutes. Four of the following symptoms must be present to meet the diagnostic criteria of panic disorder.

  • Shortness of breath
  • Chest pain
  • Excessive sweating
  • Palpitations or tachycardia
  • Dizziness or feeling faint
  • Trembling or shaking
  • Intense feeling of terror
  • Nausea
  • Tingling or numbness in fingers or toes
  • Derealisation/depersonalisation
  • Dry mout
  • Chills or hot flashes
  • Visual disturbances
  • Fear of dying
  • Fear of losing control or impending doom

[1][2][4][6][13][14][15]

Effects of symptoms

Symptoms of panic disorder have physical, behavioral and cognitive effects:[13]

  • Physical:
    • Tachycardia
    • Palpitations
    • Shortness of breath
    • Sweating or chills
    • Chest pain
    • Increased respiration rate
    • Increased blood pressure
    • Increased muscle tention
    • Irritibility
    • Decreased sex drive
    • Dizziness
    • Nausea
    • Duarrhiea
    • Muscle tension
  • Behavioral
    • Sleep disturbance
    • Difficulty with memory or concentration
    • Apprehension
    • Irritability
    • Hyper-alertness
    • Uncertainty
  • Cognitive
    • Fear of losing one’s mind
    • Fear of losing control
    • Sense of terror
    • Fear of dying

Differential diagnosis

  • Cardiovascular:
    • Arrythmias
    • Supraventricular tachycardia
    • Cardiac failure
    • Angina
    • Anaemia
  • Pulmonary:
    • Asthma
    • Hyperentilation
    • Pulmonary embolism
  • Neurological:
  • Enocrine disorders:
    • Hyperthyroidism
    • Hyperparathyroidism
    • Pheochromocytoma
    • Addison's disease
    • Carcinoid
    • Hypoglucemia
  • Other:
    • Anaphylaxis
    • Electrolyte imbalance
  • Uncommon:
    • Obsessive-compulsive disorder
    • Hypochondriasis
    • Factitial disease
    • Malingering

[1][16][17]

Diagnostic procedures

According to the Diagnostic and Statistical Manual of Mental Health Disorders (DSM), the following criteria is used in the diagnosis of panic disorder.[18]

Panic disorder without agoraphobia

  • Both of the following:
    • Recurrent unexpected panic attacks
    • At least one of the attacks have been followed by one month or more of the following:
      • Persistent concern about having additional attacks
      • Worries about the implications or consequences of the attack (e.g. "going crazy", having a heart attack, losing control)
      • Significant change in behavior related to the panic attacks
  • Absence of agoraphobia
  • Panic attacks are not the direct physiological result of a substance or general medical condition (e.g. hyperthyroidism)
  • The panic attacks are not better accounted for by another mental disorder (e.g. social phobia, specific phobia, obsessive-compulsive disorder, post-traumatic stress disorder, separation anxiety disorder)

Panic disorder with agoraphobia

  • Both of the following:
    • Recurrent unexpected panic attacks
    • At least one of the attacks have been followed by one month or more of the following:
      • Persistent concern about having additional attacks
      • Worries about the implications or consequences of the attack (e.g. "going crazy", having a heart attack, losing control)
      • Significant change in behavior related to the panic attacks
  • Presence of agoraphobia
  • Panic attacks are not the direct physiological result of a substance or general medical condition (e.g. hyperthyroidism)
  • The panic attacks are not better accounted for by another mental disorder (e.g. social phobia, specific phobia, obsessive-compulsive disorder, post-traumatic stress disorder, separation anxiety disorder)

Diagnostic criteria

Diagnostic Criteria for panic attacks include the presence of four or more of the following symptoms which develop with a rapid onset and peak within 10 minutes:[7]

  • Palpitations
  • Sweating
  • Trembling or shaking
  • Sensations of shortness of breath or smothering
  • Feeling of choking
  • Chest pain or discomfort
  • Nausea or abdominal distress
  • Feeling dizzy, unsteady, lightheaded or faint
  • Feelings of unreality or feelings of being detached from oneself
  • Fear of losing control or going crazy
  • Fear of dying
  • Paresthesias
  • Chills or hot flashes

Special investigations

To rule out other conditions, the following diagnostic and lab tests might be necessary:[4]

Associated comorbidities

  • Alcoholism
  • Depression (lifetime prevalence of 35-38% in patients with panic disorder)[7]
  • Drug abuse
  • Post-traumatic stress disorder
  • Social phobia
  • Mitral valve prolapse
  • Migraine
  • Labile hypertension
  • Suicide

[7][12][19][20]

Medical management

Medical management are usually lead by a psychologist and includes a combination of the following:[20]

  • Psycho-education:
    • Educating the patient about the disorder so they can develop an understanding and acceptance of their diagnosis. Offering resources to facilitate their understanding. 
  • Lifestyle changes:
    • Avoiding stimulants such as caffeine, or other substances and medication that will hinder recovery
    • Regular moderate exercise
    • Stress management
  • Cognitive behavioral therapy:
    • 75-95% of patients are panic free after treatment while maintaining improvements for at least 2 years
    • Patient becomes aware of thought, emotions and beliefs of situations triggering panic attacks
    • Helps patient identify inaccurate thinking
    • Limitation: not offered by all psychologists and psychiatrists
  • Breathing/relaxation exercises:
    • Slow breathing and graded muscle relaxation techniques
  • Cognitive restructuring:
    • Working with patient to identify inaccurate cognitions and replacing them with realistic ideas
  • Graded exposure
    • Reintroducing the patient to feared stimuli to test their anxiety control
    • Progress as tolerated to more challenging feared stimuli

Pharmacological management

Anti-Depressants called Selective Serotonin Reuptaked Inhibitors (SSRI) are the first line of treatment and most commonly used medications to treat panic disorder. It may take a few weeks before anti-depressants begin to take effect, therefore, it is advised to take this medication continuously rather than only when panic attacks occur.[12] Some of the common SSRI's used to treat panic disorder include:[3]

  • Fluoxetine (Prozac)
  • Sertraline (Zoloft)
  • Paroxetine (Paxil)
  • Fluvoxamine (Luvox)
  • Citalopram (Celexa)
  • Escitalopram (Lexapro)

Benzodiazepines may be used if SSRI’s do not help. This is a form of anti-anxiety medication which provides rapid relief of symptoms during a panic attack.  The effects can occur as quickly as 30 minutes after taking the medication. However, this is considered to be the second line of treatment for panic disorder due to the highly addictive qualities and withdrawal symptoms that occur as a result of taking this medication.[12] Examples include:

  • Alprazolam (Xanax)
  • Clonazepam (Klonopin)
  • Lorazepam (Ativan)

Physioterapy management

Physiotherapists are not involved in the primary treatment of panic disorder, however, it is important to be aware of the clinical presentation of this disorder.  Patients who present to physiotherapy with panic disorder may have symptoms that mimic other medical conditions, therefore, it is necessary for the physiotherapist to recognize the need for medical referral.[16] It is also possible for patients with panic disorder to present with signs and symptoms that mimic musculoskeletal dysfunction. These are the patients who will be experiencing muscle aches as a result of panic attacks. The physiotherapist must obtain a detailed history from the patient and perform an extensive evaluation in order to determine the source of the muscle aches.

Physiotherapists can play a role in helping to decrease the occurrence of panic attacks by encouraging the patient to exercise. Studies have shown that acute bouts of exercise can help to reduce or prevent the occurrence of anxiety attacks.[22] One of the suggested causes of panic disorder mentioned previously relates to abnormalities within the brain. However, exercise should be encouraged to allow the release of endorphins or the “feel good hormones” that leave a person feeling calm, energized and optimistic. Exercise also plays a role in increasing serotonin levels which in turn works to improve mood. According to the United States Surgeon General, physical activity helps to relieve symptoms of anxiety and depression as well as improve mood.

If treating patients with panic disorder in the physiotherapy setting, clinicians should be advised to educate their patients on the benefits of exercise which will help manage panic disorder. It is also recommended to be aware that it is possible for exercise to induce panic attacks. Therefore, therapists should pay close attention to changes in signs and symptoms of these patients during exercise.

Resources

References

  1. 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 Oosthuizen P, Niehaus D, Stein D, Seedat S. Die angsversteurings. In: Emsley FA, Pienaar WP editors. Handboek vir psigiatrie, 2de uitgawe. Departement Psigiatrie: Universteit van Stellenbosch. Stellenbosch: Geestesgesondheid Inligtingsentrum van SA. 2005. pp. 59-
  2. 2.0 2.1 2.2 2.3 National Center for Biotechnology Information. PubMed Health. Panic Disorder. http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0001922/ (Accessed 13 March 2011).
  3. 3.0 3.1 Medline Plus. Panic Disorder. http://www.nlm.nih.gov/medlineplus/panicdisorder.html (accessed 13 March 2011).
  4. 4.0 4.1 4.2 WebMD. Anxiety and Panic Disorder Guide. http://www.webmd.com/anxiety-panic/guide/mental-health-panic-disorder (Accessed 13 March 2011).
  5. Torpy JM, Burke AE, Golub RM. Panic disorder. JAMA 2011;305:1256.
  6. 6.0 6.1 6.2 6.3 Barlow DH. Anxiety and its disorders. 2nd edition. New York: Guilford Publications, Inc., 2002.
  7. 7.0 7.1 7.2 7.3 7.4 Psychiatry Online. APA Practice Guidelines. http://www.psychiatryonline.com/content.aspx?aID=155332 (accessed 27 March 2011).
  8. 8.0 8.1 8.2 Friedlander AH, Marder SR, Sung EC, Child JS. Panic disorder: psychopathology, medical management and dental implications. The Journal of the American Dental Association 2004;135(6):771-8.
  9. National Alliance on Mental Illness. Panic Disorder. http://www.nami.org/Template.cfm?Section=By_Illness&Template=/TaggedPage/TaggedPageDisplay.cfm&TPLID=54&ContentID=23050 (Accessed 31 March 2011).
  10. Mathew AR, Norton PJ, Zvolensky MJ, Buckner JD, Smits JA. Smoking behavior and alcohol consumption in individuals with panic attacks. Journal of Cognitive Psychotherapy 2011;25:61-70.
  11. Medicine Net. Panic Attacks (Panic Disorder). http://www.medicinenet.com/panic_disorder/article.htm (Accessed 27 March 2011).
  12. 12.0 12.1 12.2 12.3 Help Guide. Panic Attacks and Panic Disorder. http://helpguide.org/mental/panic_disorder_anxiety_attack_symptom_treatment.htm (Accessed 27 March 2011).
  13. 13.0 13.1 Goodman CC, Fuller KS. Pathology: Implications for the Physical Therapist. 3rd edition. St. Louis, Missouri: Saunders Elsevier, 2009.
  14. Anxiety Disorders Association of America. Panic Disorder and Agoraphobia. http://www.adaa.org/understanding-anxiety/panic-disorder-agoraphobia (accessed 15 March 2011).
  15. American Psychological Association. Anxiety. http://www.apa.org/topics/anxiety/panic-disorder.aspx (accessed 27 March 2011).
  16. 16.0 16.1 Goodman CC, Snyder TK. Differential Diagnosis for Physical Therapists: Screening for Referral. 4th edition. St. Louis, Missouri: Saunders Elsevier, 2007.
  17. Mend Solutions. Panic Disorder Differential Diagnosis. http://www.mend.net/panic/DifferentialDX.html (Accessed 28 March 2011).
  18. PSYweb complete mental health site. DSM-IV DSM Disorders Diagnostic Criteria. http://www.psyweb.com/DSM_IV/jsp/dsm_iv.jsp (Accessed 30 March 2011).
  19. National Institute of Mental Health. Panic Disorder. http://www.nimh.nih.gov/health/publications/anxiety-disorders/panic-disorder.shtml (Accessed 14 March 2011).
  20. 20.0 20.1 http://www.ncbi.nlm.nih.gov/pubmed/15999167
  21. Iglesias A, Iglesias A. Awake-alert hypnosis in the treatment of panic disorder: A case report. American Journal of Clinical Hypnosis 2005;47(4):249-57.
  22. Strohle A, Feller C, Marlies O, Godemann F, Heinz A, Dimeo F. The acute antipanic activity of aerobic exercise. Am J Psychiatry 2005;162:2376.