Guidance for the management of headache in sport on behalf of The Royal College of General Practitioners and The British Association for the Study of Headache

Abstract

Headache is prevalent within the community and can have an impact on sport in both the amateur and elite player, either coincidentally or as a direct result of participation. Against a background of a limited evidence base, this paper suggests how headache can be classified within this context and offers guidance for treating both the amateur and elite athlete. The impact of headache in sport may be unrecognised and undertreated, and further research is needed in this area.

Introduction

Headache is a common problem, with three-month prevalence of 70% in the United Kingdom (1). Migraine alone affects 7.6% of males and 18.3% of females (2). Despite the substantial impact of headache, the needs of many people with headache are unmet (3,4). When they do seek help, the diagnosis is often incorrect and the condition poorly managed (5).

Headache can have an impact on sport at both the amateur and elite levels. Against a background of policy initiatives to increase activity and the fact that headache sufferers may be less active (6), an understanding of the relationship between sport and headache and options for management are important for health care practitioners at all levels.

Estimates of the prevalence of exertional headache range between 12% and 30% (7,8) but the prevalence of headache specifically related to sport is not well described. A study of university students found that 35% experienced sport- or exercise-related headaches (9). A study of Australian footballers found that 49% of respondents reported headache during competitive play and 60% during training (10). In a study of American football players, 85% had suffered headache during play, 21% during their most recent match. However, the majority of these headaches were related to trauma (11). A small study of Italian soccer players found a prevalence of 3.6% of reported headache during a season, all of which fulfilled the International Classification of Headache Disorders, second edition (ICHD-II), criteria for tension-type headache (TTH). No attacks occurred during competition (12).

The pathogenesis of headache has only relatively recently begun to be better understood (13). Headache can arise from direct activation of dural pain fibres, central activation of trigeminal pain fibres supplying the large cerebral and pial vessels and large venous sinuses, or can arise from facial or neck structures, or from dysfunction of brain centres normally concerned with sensory modulation. Headache that occurs in sport can be primary or secondary. Although strict International Headache Society (IHS) diagnostic criteria are defined, these are invariably relaxed in clinical practice.

The aim of this paper is to provide a practical classification of headache syndromes that may occur with sport and offer guidance for their management in both the elite and amateur sports player.

Headache classification in sport

A previous study characterised sports headache as “effort migraine” (9%), “trauma trigger migraine” (6%), “exertional headache” (60%), “post-traumatic headache” (22%) and miscellaneous 3% (14). The relevant IHS classifications are primary exertional headache, cough headache (previously known as Valsalva manoeuvre headache) and the appropriate secondary headaches. From a practical perspective, the classification can be somewhat cumbersome in specific settings such as sport. In this paper, four categories of sport-related headache are defined, providing a pragmatic organisation for practitioners:

1. A recognised headache syndrome (migraine, TTH, cluster headache) coincidental to sporting activity.

2. A recognised headache syndrome (migraine, TTH) induced by sporting activity.

3. Headache arising from mechanisms that occur during exertion. These can be primary where the exact mechanism is not understood, or secondary where a direct causal factor can be demonstrated:

3a. Headache related to changes in cardiovascular parameters (increase in cardiac output and raised venous pressure).

3b. Headache related to trauma.

3c. Headache arising from structures in the neck.

4. Headache arising from mechanisms that are specific to an individual sport.

These four categories are further discussed below.

A recognised headache syndrome (migraine, TTH, cluster headache) coincidental to sporting activity

Tension-type headache

TTH is the most common headache in the population (15). The headache is dull, occipital and bilateral. However, it is usually improved by exercise, alleviated by simple analgesia and unlikely to be a problem in sport.

Migraine

The lifetime prevalence of migraine is 16% (16). Although regular exercise can help reduce the frequency, intensity and duration of migraine attacks (17), migraine is likely to be the most common coincidental primary headache during sport.

For the acute attack, triptans, serotonin 5-HT_1B/1D receptor agonists, are the mainstay of treatment. The experience of administration during sport is limited to one small study of 38 attacks in Australian professional footballers using intranasal sumatriptan (18). There was a good response with no major side effects, but minor side effects were reported in over 70% of cases.

Apart from the potential impact of triptans on performance, particularly from a cognitive perspective, there are theoretical concerns regarding the potential for coronary vasoconstriction. For the amateur sports player, a non-steroidal anti-inflammatory, with or without a prokinetic or anti-emetic, would be a simple, generally safe, first choice. If triptans are necessary during sport in amateurs or in elite players, underlying cardiac pathology, in particular ischaemic heart disease and cardiomyopathy, should be excluded with an exercise electrocardiogram (ECG) and echocardiogram. Any of the first-line triptans, such as sumatriptan, almotriptan, eletriptan, rizatriptan or zolmitriptan, represent reasonable first choices. Triptan nasal sprays have the theoretical advantage of faster action and to some extent are able to bypass gasotrointestinal absorption limitations. Triptan formulations that are rapidly dissolved are not faster acting but may be more convenient in the sporting context. Lack of or poor response to a triptan is not a class effect, and in this case an alternative from the class should be tried.

Beta-blockers are a first choice in the preventive treatment of migraine in routine practice. Propranolol 20 mg tds, increasing to 40 mg tds, is commonly used, but atenolol is convenient, cheap and probably works just as well starting with 25 mg a day and increasing at weekly intervals by 25 mg until effective, side effects or a maximum dose of 100 mg a day is obtained. The use of beta-blockers in many sports has obvious implications for limitation of performance and these are banned in many professional sports. Topiramate, sodium valproate, gabapentin, cyproheptadine or pizotifen are reasonable alternative choices with appropriate monitoring for potential side effects. The evidence base in this setting is very limited.

Cluster headache

Cluster headache has a very high impact but is rare, affecting 0.1% of population (19). The cluster attack is predominantly unilateral, peri-oribital, excruciatingly painful and occurs in short bursts over a “cluster period”, associated with peri-oribital or nasal autonomic features. Ninety percent of attacks occur daily for six to eight weeks, typically once or twice a year, with spontaneous resolution. Sporting activity will be unlikely during the cluster period.

Short-term oral steroids and oxygen will be contraindicated for the elite athlete. Triptans, either intranasal sumatriptan or zolmitriptan or subcutaneous sumatriptan (20), and oxygen (21) are effective. Cardiovascular concerns are the same as those outlined for the treatment of migraine. For prolonged bouts of episodic or for chronic cluster headache, verapamil is the preventive agent of choice but may cause cardiac conduction delays, and six monthly ECGs should be undertaken. It is best avoided in elite athletes, where lithium 600–1200 mg daily or topirimate 50 mg bd can be used. Greater occipital nerve injection may be a useful intervention in episodic cluster headache (22) but again, steroids will be contraindicated for the elite athlete.

A recognised headache syndrome (migraine, TTH) induced by sporting activity

Over 20% of migraineurs experience migraine precipitated by physical activity (23). It has been suggested that exercise-induced migraine can be prevented by aerobic warm-up prior to activity (24), but the evidence base is poor. Cross-sectional studies have suggested that TTH does not restrict activities significantly (25).

A reasonable approach would be to use indometacin 25–50 mg one hour before onset of exertion. If this is not successful, 25–50 mg tds over the 24-hour period prior to exertion may be considered. Alternatively, one could consider a triptan dosed appropriately prior to exertion. Similarly, if the elite athlete has consistent problems, a triptan administered 30–60 minutes before activity with the provisos mentioned above could be tried, although the experience with triptans used in this way is not positive. If an elite athlete has consistent problems with sports-induced migraine, it may be best to start a preventive as outlined above. There is no evidence that cluster headache is induced by activity.

Headache arising from mechanisms that occur during exertion

The physiological processes that occur during sport can induce headache. If no underlying structural cause can be identified, these headaches are termed primary even though pain-inducing mechanisms may be inferred. If there is a structural abnormality, the headache is termed secondary.

Headache related to changes in cardiovascular parameters

Headache associated with increased cardiac output. Headache associated with exercise when cardiac output is raised is the most common type of sporting headache. The formal IHS criteria classifies a “primary exertional headache” as a pulsating headache lasting from five minutes to 48 hours and brought on by and occurring only during or after physical exertion, for which no underlying cause can be identified. The mechanism is unknown. The headache is often described as migrainous in character, exacerbated in hot weather and at altitude and typically occurs during the period of maximum exertion, although it can be experienced during warm-up or after exertion.

Although studies are small, estimates of a secondary cause range between 10% and 23% (26,27). Risk factors for secondary headaches are age, late onset of headache during activity and lack of responsiveness to indometacin.

All exercise-induced headaches should be investigated with an MRI of the brain, blood pressure and ECG, blood screening for renal and liver function, haematology, thyroid disease and diabetes. Urinary catecholamines should be considered. Arnold-Chiari malformations, a structural abnormality in which the lower part of the cerebellum protrudes through the foramen magnum into the spinal subarachnoid space, and neoplasms are the most common secondary pathology. Subarachnoid haemorrhage and arterial dissection are the most common cause of acute presentations. Rarely, headache can be a direct and isolated symptom of cardiac ischaemia but the mechanism is unknown (28,29).

Having excluded a secondary cause, the treatment of primary exercise induced headache is anecdotal. Gradual warm-up exercise programmes have been advocated (24) but for short-term prevention, indometacin is the treatment of choice (30). (See above.) For more frequent occurrence, a beta-blocker is the drug most recommended providing there is no contra-indication for the elite athlete. There is little experience with other agents but the preventative migraine agents described above can be tried.

Headache due to raised venous pressure. This headache is more common in sports such as weight lifting and presumably caused by distension of the cerebral venous system. As the small number of studies conflate this type of headache with exertional headache, and indeed in some types of exertion this may be the mechanism, the prevalence is unknown. An important secondary cause is an Arnold-Chiari malformation, which must be excluded with neuroimaging with MRI. However, the indications for surgical treatment within the sporting context are contested.

When no underlying cause can be identified, this headache is classified by the IHS as “primary cough headache”, although the previously used term Valsalva manoeuvre headache is probably more appropriate. The diagnostic criteria are sudden onset lasting from one second to 30 minutes, brought on and occurring only in association with coughing, straining or Valsalva manoeuvre. Indometacin is claimed to be effective although a positive response has been reported in some cases where there is an underlying cause.

Headache related to trauma

Head injury involves shearing due to linear acceleration/deceleration or rotational forces. The degree of injury does not always correlate with headache symptoms and the mechanisms that generate pain are poorly understood. Headache may be due to direct stress acting on dural structures or secondary mechanisms due to bleeding or axonal damage. The headache can occur immediately or within the first week following an injury. Later-onset headaches have been described but their causality is contested.

As published studies are not case controlled, the exact relationship between headache and trauma is not clear. A variety of pain patterns may develop, some of which resemble those of primary headache disorders. TTH is the most common. In some cases migraine, known as “footballers’ migraine” can be triggered by mild head trauma (31,32). More rarely, a cluster headache–like syndrome has been described (33). Alternatively, a preexisting primary headache can be made worse in close temporal relationship to trauma.

Chronic post-traumatic headache is a headache that persists for three months after head trauma in the absence of a demonstrable traumatic brain lesion and may be due to maladaptive central sensitisation. It is invariably associated with a number of other symptoms, such as dizziness, difficulties in concentration and insomnia, that form a post-traumatic syndrome. The relationship between the severity of the injury and severity of the post-traumatic syndrome is not always direct.

There is no evidence base to inform the treatment of traumatic headache. The first line of treatment is symptomatic, and medication overuse headache is always a cause for concern if analgesia is taken on more that three days in each week over the longer term. Amitriptyline can be effective (34). From a practical perspective, it is recommended to start with 10 mg and increase by 10 mg each night every four to ten days until side effects are problematic or a maximum dose of 1–1.5 mg per kg body weight is reached. Developing secondary causes, such as intracerebral or subdural haemorrhage and more rarely vertebral artery dissection, should not be overlooked.

Headache arising from structures in the neck

Trauma to the neck can induce or exacerbate a cervical lesion with subsequent referred pain to the head via the upper cervical nerves. For a cervicogenic headache to be diagnosed, the IHS criteria require:

evidence of a disorder within the cervical spine or soft tissues of the neck as a valid cause of headache;

clinical signs that implicate a source of pain in the neck or the abolition of headache following a diagnostic blockade;

pain resolving within three months after successful treatment of the causes of lesion or disorder.

From a practical perspective, if the patient is able to demonstrate full movement of the neck with no local tenderness, cervicogenic headache can be excluded.

Headache arising from mechanisms that are individual to a specific sport

A number of headaches unique to a sport have been described which have a specific aetiology. For example, headache in spinning figure skaters is thought to be due to a centrifugal effect causing intracranial ischaemia (35). External compression headache is seen in swimmers due to mask pressure (36). High altitude headache is recognised as an accompaniment of acute mountain sickness and is thought to be due to a vascular phenomenon (37). Diving headache occurs as a result of CO₂ intoxication (38).

Conclusion

There are a number of problems with the study of headache in sport: the evidence base is very limited and studies are retrospective leading to recall bias; formal diagnostic criteria are rarely used; the pathogenesis of the majority of headaches is poorly understood and different types of activity may lead to different pathophysiological mechanisms. The impact of headache on sport is also likely to reflect the perspective of headache sufferers in the community (i.e. stigmatised, largely unrecognised and inadequately managed with the needs of many sufferers unmet). For the research community, a useful first step would be to formally quantify the prevalence of this problem.

Further research is needed to define more accurately the extent of the problem and options for management. An important first step is an awareness of the problem by the general practitioner, sports physician and those involved in sport at all levels.