Chronic headaches affect 20% of the United States population. Most of these headaches are of the tension type, followed in incidence by migrainous, mixed and cluster forms. One type of headache, the exertional headache, affects far fewer people but warrants attention. Misdiagnosis of exertional headache can have long-lasting effects.

Approximately 1% of U.S. residents experience exertional headache, a severe headache that interferes with activity.¹ The majority of exertional headaches are benign in nature, but they can be a presenting symptom of disease.²

These benign headaches, also known as indomethacin-responsive headaches, are induced by cough, sexual activity or exercise. This exercise encompasses physical effort, exertion, trauma and cervicogenic factors. By definition, benign exertional headaches (BEH) are precipitated by exertion. The exertional trigger can range from weight lifting to water skiing to gardening.

Characteristics of BEH
The most common BEH patients are men in their 20s.^3,4,5 Generally, the headache comes on suddenly with an activity that produces a valsalva maneuver. It is often occipital, throbbing and severe for a few minutes, then resolves into a dull ache that lasts 4 to 6 hours (although it can last up to 24 hours).⁴ Repeating the activity triggers the same response, and not participating in the triggering activity results in absence of the headache. Associated symptoms can include nausea, vomiting and photophobia.

Assessment of the patient's current medication use is important because headache is a common side effect of pharmacologic therapy.⁶ Patients with BEH may have a family history of migraine. Social and occupational histories may provide insight about environmental exposure to chemicals that could potentially trigger headache. In one study, 25% of subjects had a respiratory infection prior to the onset of BEH, raising speculation about a viral component.⁷

Because BEH can be associated with benign sexual headaches, take a sensitive sexual history to ascertain whether the patient has similar headaches with orgasm.⁵ Also ask about any orofacial pain. In one published report, patients with orofacial pain were treated with indomethacin (Indocin) after pathology was ruled out. Improvement suggested an atypical presentation of BEH.

Exertional headache can be classified as benign or symptomatic.³ Symptomatic exertional headaches fit the diagnostic criteria but have associated pathology. With treatment, the headaches resolve. Conversely, benign exertional headaches fit the criteria and no associated pathology exists.

Diagnostic Testing
Helpful serologic information includes a sedimentation rate and a complete blood count with differential, to look for evidence of infection or inflammation. Further exploration with magnetic resonance imaging and computed tomography can rule out intracranial pathology when warranted. Though expensive, these tests are important because lesions of the posterior fossa can present as exertional headache.^5,8 Suspect intracranial pathology onset of severe headache is severe, with increasing intensity that persists and is frequently unilateral. The headache may be associated with night waking, weight loss, fever, malaise and focal neurologic signs and symptoms.

A lumbar puncture is indicated when suspicion is high for subarachnoid hemorrhage (SAH).⁵ Patients with evidence of coronary artery disease should undergo a Thallium stress test because exertional headache can be caused by a form of angina known as cardiac cephalgia.⁹

Assessment
The differential diagnoses for BEH include other exercise-induced headaches, SAH, intracranial pathology, cardiac cephalgia and infectious processes. The source of the infectious process could be intracranial or dental. The more rare etiologies are Chiari type I malformation, pseudotumor cerebri, cortical vein thrombosis, sagittal sinus thrombosis, and pheochromocytoma.⁷

Effort headaches are associated with aerobic exertion such as running and differ from exertional headaches in that their onset is insidious as opposed to sudden. Posttraumatic headaches have a variable onset and duration and are a result of trauma to the head and neck. Cervicogenic headaches are insidious in onset and produce constant pain for days. They are a result of abnormalities of the joints, muscles, fascia and neural structures of the cervical spine. Cervicogenic headaches tend to be unilateral and have associated visual disturbances.⁶

Suspect SAH when symptoms are particularly severe, with long-lasting paroxysmal pain. Signs of meningeal irritation or focal neurologic deficits may be present. The symptoms may present similarly to benign exertional headache, so a diagnostic work-up and cerebrospinal fluid examination are essential to rule out SAH.³ Intracranial disease such as posterior fossa or supratentorial space-occupying lesions, trauma, basilar impression or platybasia and syrinx have been diagnosed in patients with BEH.² Cardiac cephalgia usually presents as exertional headache associated with the onset of vigorous exercise. It subsides with rest and anti-angina treatment. Consider this diagnosis in patients older than 50 and patients with cardiac risk factors.⁹ If the patient presents with hypertension as well, a 24-hour urinalysis to rule out pheochromocytoma is indicated.

Once pathology is ruled out, BEH becomes a diagnosis of exclusion. Consider the diagnosis confirmed when the patient responds positively to indomethacin.^8,10

Pathology
Theories about the pathophysiology of exertional headache are numerous. Angiographic evidence has identified arterial dilatation or spasm as a possible factor.¹¹ Venous sinus dilatation or spasm can be contributory, a recent study suggests.¹² Hypoperfusion might be another culprit, according to a single case study using single-photo-emission computed tomography of the brain.¹³ The valsalva maneuver apparently increases arterial pressure in the central nervous system and diminishes venous blood return, leading to dilatation of the venous sinuses and veins at the base of the brain.

Treatment Plan
Reassure patients with BEH that no life-threatening pathology exists and educate them about proper symptom management. Behavioral interventions are primary. Counsel patients to avoid the trigger activity if possible. Avoiding caffeine and warming up before participating in the trigger activity are helpful adjuncts.⁶

Pharmacologic interventions can be useful. Indomethacin, 25 mg to 150 mg daily or 75 mg sustained-release form taken 2 hours before exercise, can help control or eliminate symptoms. Most BEH headaches resolve over time, but in some cases they persist for years. In a quasi-experiment clinical trial, 15 subjects took indomethacin at doses to control symptoms and 13 achieved relief. When the drug was discontinued 6 to 12 months later, all subjects had recurrence of the symptoms.⁸ Discussing realistic expectations for pharmacologic therapy will help patients understand and adhere to the care plan you recommend. Education and interventions about gastrointestinal side effects of indomethacin is warranted. Propranolol, ergotamine and intravenous dihydroergotamine have been used with varying results.

A 1968 study of 103 subjects with diagnosed BEH documented 10 eventual cases of organic brain disease.⁷ The study was performed before advancements in identifying cranial lesions, but it underscores the need to remain vigilant about symptom progression and lack of response to indomethacin. Patients who do not respond to this treatment require re-evaluation and further study.

References

1. Rasmussen BK. Epidemiology of headache. Cephalalgia. 1995;15(1):45-68.

2. Sands GH, Newman L, Lipton R. Cough, exertional, and other miscellaneous headaches. Medical Clinics of North America. 1991;75(3):733-747.

3. Pascual J, Iglesias F, Oterino A, et al. Cough, exertional, and sexual headaches: an analysis of 72 benign and symptomatic cases. American Academy of Neurology. 1996;46:1520-1524.

4. Pascual J, Oterino A, Iglesias F, et al. Cough headache. Headache Quarterly, Current Treatment and Research. 1996;7(3):201-206.

5. Silbert PL, Edis RH, Stewart-Wynne EG, Gubbay SS. Benign vascular sexual headache and exertional headache: interrelationships and long term prognosis. Journal of Neurology, Neurosurgery, and Psychiatry. 1991;54:417-421.

6. McCrory P. Recognizing exercise-related headache. The Physician and Sportsmedicine. 1997;25(2):33-43.

7. Rooke ED. Benign exertional headache. Medical Clinics of North America. 1968;52(4):801-808.

8. Diamond S. Prolonged benign exertional headache: its clinical characteristics and response to indomethacin. Headache. 1982;22:96-98.

9. Lipton RB, Lowenkopf T, Bajwa ZH, et al. Cardiac cephalgia: a treatable form of exertional headache. American Academy of Neurology. 1997;49:813-816.

10. Headache Classification Committee of the International Headache Society. Classification and diagnostic criteria for headache disorders, cranial neuralgias and facial pain. Cephalalgia. 1988;8(suppl 7):1-96.

11. Silbert PL, Hankey GJ, Prentice DA, Apsimon HT. Angiographically demonstrated arterial spasm in a case of benign sexual headache and benign exertional headache. Australia and New Zealand Journal of Medicine. 1989;19:466-468.

12. Markus HS, Harrison MJG. Estimation of cerebrovascular reactivity using transcranial Doppler, including the use of breath-holding as the vasodilatory stimulus. Stroke. 1992;23:668-673.

13. Bosoglu R, Ozbenli R, Bernay I, et al. Demonstration of frontal hypoperfusion in benign exertional headache by technetium-99m-HMPAO SPECT. The Journal of Nuclear Medicine. 1996;37(7):1172-1174.