Synonym: panic attacks (recurrent)
Panic disorder can be a severe and disabling illness and is common in primary care. It can be difficult to assess when it presents acutely, as many symptoms may also be experienced with physical illness. Those who experience panic disorder often present repeatedly to their GP or local emergency department with worrying episodes of multiple symptoms that the patient may ascribe to life-threatening illness.
This condition often co-exists with agoraphobia - the avoidance of exposed situations for fear of panic or inability to escape. Agoraphobia is not a stand-alone diagnosis and occurs very rarely without panic disorder. Panic disorder is often classified into panic disorder with, or without, agoraphobia. Social anxiety disorder can often co-exist and is diagnosed where the situations avoided are predominantly social and interactive in nature.
The first panic attack may be associated with a stressful episode but gradually the attacks become dissociated and occur 'out of the blue'. It is a chronic condition with relapses and leads to much distress and social dysfunction. Gamma-aminobutyric acid (GABA) receptor dysfunction is thought to play an important role in panic disorder pathophysiology.
Panic attacks must be associated with >1 month's duration of subsequent, persisting anxiety about recurrence of the attacks, the consequences of the attacks, or significant behavioural changes associated with them.
A panic attack is defined as a discrete episode of intense subjective fear, where at least four of the characteristic symptoms, listed below, arise rapidly and peak within 10 minutes of the onset of the attack:
- Attacks usually last at least 10 minutes but their duration is variable.
- The symptoms must not arise as a result of alcohol or substance misuse, medical conditions or other psychiatric disorders, in order to satisfy the diagnostic criteria.
Characteristic symptoms experienced during panic attacks
Panic disorder manifests as the sudden, spontaneous and unanticipated occurrence of panic attacks, with variable frequency, from several in a day to just a few per year:
- Palpitations, pounding heart or accelerated heart rate.
- Trembling or shaking.
- Dry mouth.
- Feeling short of breath, or a sensation of smothering.
- Feeling of choking.
- Chest pain or discomfort.
- Nausea or abdominal distress.
- Feeling dizzy, unsteady, light-headed or faint.
- Derealisation or depersonalisation (feeling detached from oneself).
- Fear of losing control or 'going crazy'.
- Fear of dying.
- Numbness or tingling sensations.
- Chills or hot flushes.
Panic disorder is defined as recurrent unexpected panic attacks.
Epidemiology and aetiology
Panic disorder is a common problem. The prevalence of panic disorder with or without agoraphobia in one UK study was 1.70%. In the USA, lifetime prevalence is estimated at 3-5.6% for panic attacks and 1.5-5% for panic disorder. Psychiatric case-finding studies of patients presenting with chest pain to emergency departments found that up to 25% satisfied criteria for panic disorder.
There are many aetiological theories, none of which is proven in isolation. Several aetiological factors may contribute to its occurrence in a given individual. The postsynaptic serotonergic/adrenergic hypersensitivity hypotheses are probably the most biologically plausible and relevant to treatment response but there are also important genetic and environmental factors involved.
Panic disorder can also be associated with the use of certain medications: selective serotonin reuptake inhibitors (SSRIs), benzodiazepine withdrawal and withdrawal from zopiclone. These should be considered in assessing any patient who presents with panic disorder.
Anxiety disorders often go unrecognised, partly because patients frequently complain of pain, sleep disturbances, or other somatic problems as their main symptom, rather than of the underlying anxiety.
Most patients are seen in general practice, although patients may present to A&E with somatic symptoms such as chest pain. As attention is given to the physical symptoms, the diagnosis of panic attacks may not be made. Therefore, a high index of suspicion is needed. Screening tools are available[6, 7].
As detailed above, the patient will describe a history of sudden onset of episodes of panic, featuring four or more of the characteristic symptoms. These will usually peak within 10 minutes and can last for 20-30 minutes but they will rarely persist beyond one hour. There is marked individual variation in the length of attacks. It is worth asking about any triggering caused by alcohol or drugs (including legal drugs such as caffeine, nicotine, complementary remedies or over-the-counter (OTC) preparations). Enquiry about other triggers for the attacks helps in constructing the differential diagnosis:
- Those that arise unexpectedly and without any obvious triggering situation or event are characteristic of panic disorder without agoraphobia.
- Those that arise in a predictable way as a follow-on to a given anxiety-provoking situation or event usually reflect a specific phobia-type diagnosis, or panic disorder with social phobia if the precipitant is a social phenomenon.
- Those that arise in an inconsistent or unpredictable way following exposure to a given anxiety-provoking situation or event suggest panic disorder with agoraphobia.
One cross-sectional study of older patients with persistent dizziness found that anxiety and/or a depressive disorder were present in 22% and this could be a presentation for conditions such as panic disorder.
There are no specific physical signs associated with the condition, unless the patient is seen during a panic attack, when increased sympathetic outflow may manifest as tachycardia, hypertension, tremors, sweating, etc.
During the panic attack the patient may be extremely preoccupied about suffering death or a severe, life-threatening physical illness. Examination of the mental status reveals no specific findings other than a reflection of anxiety and/or urgency in their appearance, speech or mood (this is not necessary to make the diagnosis). The patient's affect should be congruent with their mental state. Thought processes should be normal and thought content should be essentially normal but may be preoccupied with death or illness. Thought content should be assessed for suicidal or homicidal ideation, or thoughts of self-harm. Judgement and insight are normally preserved. Abnormalities in thought processes or content (other than impulsive thoughts of suicide or self-harm) suggest alternative psychiatric diagnoses. The presence of incongruent affect should raise concerns that panic disorder is the wrong diagnosis.
Panic disorder is frequently associated with agoraphobia (affecting about 26% of sufferers) and/or social phobia (affecting about 33% of sufferers). There is a significant association with mood disorders, particularly depression, with lifetime prevalence rates as high as 50-60%. There appears to be a higher risk of suicide attempts than in the general population. One study found that 98% of panic disorder patients had at least one comorbid disorder. Major depressive disorder and other anxiety disorders were the most common. The other anxiety disorders tended to be persistent, although other depressive disorders and alcohol use disorders had high remission rates. Alcohol and substance misuse can complicate the picture and these can be used in some cases to self-medicate.
These may co-exist but one would not generally use the term panic disorder if the symptoms arise directly from the physical illness. Cardiovascular disease such as mitral valve prolapse, cardiomyopathy and hypertension are associated. Chronic obstructive airways disease and migraine headaches are also present in a larger proportion of sufferers than chance would suggest, as are functional disorders such as irritable bowel syndrome and tension-type headache. A link with joint hypermobility disorder has been elucidated, further suggesting a genetic basis for panic disorder.
Although a good description of the episode may suggest a panic attack, it is important to exclude other organic conditions. For example, there is a rare case report of a cingulate ganglioma presenting as panic attacks in a teenager. More typical alternatives include:
- Agoraphobia (often co-exists).
- Social anxiety disorder (often co-exists).
- Anxiety disorders, including generalised anxiety disorder (may co-exist).
- Adjustment disorders.
- Bipolar disorder.
- Dissociative disorders.
- Factitious illness.
- Somatisation disorder.
- Mental symptoms arising as a result of physical illness.
- Obsessive-compulsive disorder.
- Specific phobic disorders.
- Post-traumatic stress disorder.
- Stimulant-drug misuse (including caffeine-related illness).
- Carcinoid syndrome.
- Hypoglycaemic episodes (possibly due to insulinoma in those not using insulin/oral hypoglycaemic agents).
- Paroxysmal cardiac dysrhythmia.
- Mitral valve prolapse.
- Myocardial infarction.
- Recurrent small pulmonary emboli.
- Epileptiform disorders, particularly temporal lobe epilepsy.
- Withdrawal from alcohol/sedatives/opiates.
- Paroxysmal vestibular disorders - eg, Ménière's disease.
There are no specific investigations to diagnose the condition but clinicians may feel inclined to refer the patient, or carry out tests to exclude underlying physical causes for the symptoms. Whilst it is important not to miss likely physical causes, one should not endlessly or excessively investigate these patients. Such a course of action can leave them with the impression that there actually is a physical problem, which their doctor(s) just can't find.
After initial exclusion of top-ranking physical causes, with the confirmation of characteristic clinical features of panic disorder, the absence of a physical cause should be clearly explained to the patient. Response to treatment will be better in those patients who accept the absence of physical causes for their symptoms and in those who have an understanding of the nature of panic disorder as a primarily mental phenomenon.
There is no high-quality, unequivocal evidence to support one psychological therapy over the others. There is also no strong evidence regarding the relative effectivess of psychological therapies and pharmacological treatment.
The National Institute for Health and Care Excellence (NICE) recommends a stepped care approach.
Step 1: recognition and diagnosis
This has been dealt with in the 'Presentation', 'Differential diagnosis' and 'Investigations' sections, above.
Step 2: treatment in primary care
- Try to involve the patient's family or carer if the patient allows this. It is important for them to understand how they can best help the patient during an attack.
- Advise avoiding anxiety-producing substances - eg, caffeine.
- It is important to exclude alcohol or drug misuse as a factor and to treat these problems if present. Reassessment after successful management of substance-related issues will reveal if this is true panic disorder. Response to pharmacological/psychological therapies is likely to be poor in the face of alcohol/drug misuse or dependence.
Offer the following interventions (listed as per NICE in the order - according to the evidence base - of duration of efficacy):
Cognitive behavioural therapy (CBT)
- Treatment focused on the recognition of factors which trigger the panic, and behavioural methods to cope with the symptoms, have been found to be very useful.
- Trained and supervised personnel should be involved in the delivery of treatment, working to empirically grounded protocols.
- 1-2 hours a week is suitable for most people over a four-month period.
- Briefer CBT of about seven hours may be appropriate for some patients, combined with self-help materials.
- More intensive CBT over a shorter period of time may be suitable for some patients.
- Overall, there is evidence of a moderate treatment effect with psychological treatments in primary care.
- Before prescribing, consider age, previous treatment, tolerability, other medication, comorbidities, personal preference, cost and risk of self-harm (SSRIs are less dangerous than tricyclics in overdose).
- Inform the patient about possible side-effects (including a temporary increase in anxiety at the start of treatment), delay in onset of effect, possible discontinuation symptoms, the length of treatment and the need to follow dosage instructions.
- Provide written information appropriate to the patient's needs.
- Start with a low dose to minimise side-effects.
- Some patients may need long-term treatments and a dose at the upper end of the range.
- Do not prescribe benzodiazepines, sedative antihistamines and antipsychotics for panic disorder.
- Antidepressant drugs have been shown to be effective in reducing the amplitude of panic, reducing frequency of, or eliminating, panic attacks and improving quality-of-life measures in this group of patients.
- Offer an SSRI licensed for this indication first-line unless contra-indicated.
- Consider imipramine or clomipramine if there is no improvement after 12 weeks and further medication is indicated (NB: neither is licensed for this indication in the UK, so document informed consent).
- Review the patient after two weeks to check for side-effects and efficacy, and at four, six and 12 weeks.
- If there has been an improvement after 12 weeks, continue for six months after the optimum dose has been reached.
- If medication is used for longer than 12 weeks, review at 8- to 12-weekly intervals.
- Follow the summary of product characteristics of the individual drugs for other monitoring requirements.
- Use self-completed questionnaires to monitor outcomes where possible.
- At the end of treatment, withdraw the SSRI gradually, as dictated by patient preference, and monitor monthly for relapse for as long as appropriate to the individual.
- If there is no improvement and a second intervention has not been tried, go to Step 3 (below).
- If there has been no improvement and a second intervention has been tried, go to Step 4 (below).
- Give the patient details of books based on CBT principles, and contact details of any available support groups. There is evidence that self-help interventions are an effective option for people with panic disorder.
- Promote exercise as part of good general health. There is some evidence of a reduction in anxiety symptoms following exercise. A systematic review suggested that the effect is not as great as antidepressants but it could be a useful adjunct.
- Patients may benefit from advice on how they can control some of their symptoms by using abdominal/diaphragmatic breathing.
- Monitor the patient on a regular basis, usually every 4-8 weeks, preferably using a self-completed questionnaire.
Reassess the condition and consider alternative treatments.
If two interventions have been offered without benefit, consider referral to specialist mental health services. Specialist treatment may include management of comorbid conditions, structured problem solving, other types of medication and treatment at tertiary centres.
The literature is contradictory about prognosis. In one study the panic disorder had a long course lasting several years. In another study in primary care only a quarter of the patients with panic disorder and agoraphobia had remission in a three-year follow up. Yet, three quarters of those with just panic disorder improved. There is an increased risk of attempted suicide for people with panic disorder.
Those who suffer can help themselves by recognising triggers to panic and ameliorating them through avoidance or CBT-based strategies. Those who have recovered should be made aware that the condition may relapse and that they should seek early help for further treatment if panic attacks return.
Further reading and references
Computerised cognitive behaviour therapy for depression and anxiety; NICE Technology Appraisal Guidance, February 2006 (last updated May 2013)
Bergstrom J, Andersson G, Ljotsson B, et al; Internet-versus group-administered cognitive behaviour therapy for panic disorder in a psychiatric setting: a randomised trial. BMC Psychiatry. 2010 Jul 210:54.
Roy-Byrne P, Veitengruber JP, Bystritsky A, et al; Brief intervention for anxiety in primary care patients. J Am Board Fam Med. 2009 Mar-Apr22(2):175-86.
Generalised anxiety disorder and panic disorder in adults: management; NICE Clinical Guideline (January 2011)
Locke AB, Kirst N, Shultz CG; Diagnosis and management of generalized anxiety disorder and panic disorder in adults. Am Fam Physician. 2015 May 191(9):617-24.
Skapinakis P, Lewis G, Davies S, et al; Panic disorder and subthreshold panic in the UK general population: Epidemiology, comorbidity and functional limitation. Eur Psychiatry. 2010 Aug 31.
Ham P et al; Treatment of Panic Disorder Am Fam Phys 2005 Feb 15
Bandelow B, Lichte T, Rudolf S, et al; The diagnosis of and treatment recommendations for anxiety disorders. Dtsch Arztebl Int. 2014 Jul 7111(27-28):473-80. doi: 10.3238/arztebl.2014.0473.
Farvolden P, McBride C, Bagby RM, et al; A Web-based screening instrument for depression and anxiety disorders in primary care. J Med Internet Res. 2003 Jul-Sep5(3):e23. Epub 2003 Sep 29.
Terluin B, Brouwers EP, van Marwijk HW, et al; Detecting depressive and anxiety disorders in distressed patients in primary care comparative diagnostic accuracy of the Four-Dimensional Symptom Questionnaire (4DSQ) and the Hospital Anxiety and Depression Scale (HADS). BMC Fam Pract. 2009 Aug 23
Maarsingh OR, Dros J, van der Windt DA, et al; Diagnostic indicators of anxiety and depression in older dizzy patients in primary care. J Geriatr Psychiatry Neurol. 2011 Jun24(2):98-107. doi: 10.1177/0891988711405332.
Tilli V, Suominen K, Karlsson H; Panic disorder in primary care: comorbid psychiatric disorders and their persistence. Scand J Prim Health Care. 2012 Dec30(4):247-53. doi: 10.3109/02813432.2012.732471. Epub 2012 Oct 31.
Garcia Campayo J, Asso E, Alda M, et al; Association between joint hypermobility syndrome and panic disorder: a case-control study. Psychosomatics. 2010 Jan51(1):55-61.
Tamburin S, Cacciatori C, Bonato C, et al; Cingulate gyrus tumor presenting as panic attacks. Am J Psychiatry. 2008 May165(5):651-2.
Pompoli A, Furukawa TA, Imai H, et al; Psychological therapies for panic disorder with or without agoraphobia in adults: a network meta-analysis. Cochrane Database Syst Rev. 2016 Apr 134:CD011004. doi: 10.1002/14651858.CD011004.pub2.
Imai H, Tajika A, Chen P, et al; Psychological therapies versus pharmacological interventions for panic disorder with or without agoraphobia in adults. Cochrane Database Syst Rev. 2016 Oct 1210:CD011170.
Kelly CM, Jorm AF, Kitchener BA; Development of mental health first aid guidelines for panic attacks: a Delphi BMC Psychiatry. 2009 Aug 109:49.
Nardi AE, Lopes FL, Freire RC, et al; Panic disorder and social anxiety disorder subtypes in a caffeine challenge test. Psychiatry Res. 2009 Sep 30169(2):149-53. Epub 2009 Aug 20.
Lewis C, Pearce J, Bisson JI; Efficacy, cost-effectiveness and acceptability of self-help interventions for anxiety disorders: systematic review. Br J Psychiatry. 2012 Jan200(1):15-21. doi: 10.1192/bjp.bp.110.084756.
Jayakody K, Gunadasa S, Hosker C; Exercise for anxiety disorders: systematic review. Br J Sports Med. 2013 Jan 7.
Francis JL, Weisberg RB, Dyck IR, et al; Characteristics and course of panic disorder and panic disorder with agoraphobia in primary care patients. Prim Care Companion J Clin Psychiatry. 20079(3):173-9.
Katzman MA, Bleau P, Blier P, et al; Canadian clinical practice guidelines for the management of anxiety, posttraumatic stress and obsessive-compulsive disorders. BMC Psychiatry. 201414 Suppl 1:S1. doi: 10.1186/1471-244X-14-S1-S1. Epub 2014 Jul 2.