What is headache?
Headache disorders are among the most common disorders of the nervous system. These include tension-type headache (TTH), migraine and chronic daily headache syndromes as well as the more rare disorders, cluster headache and trigeminal neuralgia.
Headache has been, and continues to be, underestimated in scope and scale and headache disorders remain under-diagnosed and under-treated throughout Europe. In terms of funding and research, despite its prevalence, headache is often overlooked by key decision makers.
Not only is headache painful, but headache disorders are also disabling. Worldwide, according to the World Health Organisation (WHO), migraine alone is one of the top ten leading causes of disability and affects 12-15% of the population.
Headache disorders impose both a social and financial burden on many sufferers. Repeated headache attacks, and often the constant fear of the next one, damage family life, social life and work life. In Europe, migraine alone costs the economy €27 billion annually in reduced productivity and work days lost .cording to the 2006 Cost of Brain Disorders in Europe paper.
The impact of headache in Europe
Headache is the most prevalent neurological symptom and is experienced by almost everyone. Headache can be a symptom of a serious life-threatening disease, such as a brain tumor, but in most cases, it is a benign disorder that comprises a primary headache such as migraine or a tension-type headache (TTH). Nevertheless, migraine and TTH can cause substantial levels of disability, not only to patients and their families but also to society as a whole owing to its high prevalence in the general population.
Unfortunately, the scope and scale of the burden of headache is underestimated, and headache disorders are universally under-recognized and undertreated. An important initiative, Lifting the Burden: The Global Campaign to Reduce the Burden of Headache, focuses on these widespread aspects of headache and is a collaboration between multinational health-care organisations and professionals to raise awareness of headache disorders in general. Another initiative, Cost of the Brain Disorders in Europe, includes migraine as a separate neurological disorder that ranks as number nine on the list of the most costly neurological disorders in both sexes, and as number three in women. TTH is the most common form of headache and is often thought of as a normal headache, in contrast to debilitating and characteristic migraine attacks or cluster headaches. Owing to its high prevalence, disability due to TTH is greater than that for migraine at the population level. Headache is among the ten most disabling disorders for both sexes and if the burden of TTH is taken into account, among the five most disabling disorders for women, in accordance with the WHO’s ranking of the most disabling disorders.
Limited data is available so far on headache disorders. In 2004 WHO identified headache as the most frequently reported neurological disorder in primary care in Europe. Primary headaches are highly prevalent, disabling, underestimated: up to 1 adult in 25 has headache every or nearly every day. WHO classified migraine alone as 19th century among all causes of years lived with disability (YLD). All headache disorders together are possibly in the top 5 causes of disability worldwide. The ECHI (European Community Health Indicators) project, funded by the Public Health Programme, has compiled generic data on migraine or frequent headaches only including 12-month prevalence, by gender, age, region, SES (Socio Economic Status) and the WHO Atlas on Country resources has focused on the compilation of data on the frequency of primary and secondary care of headache in Europe. To date, only pharmaceutical companies have drawn-up some evaluation on parts of the global burden of headache. There is no data at European level on prevalence and global impact of headache.
 Rigmor Jensen, Lars J Stovner, Lancet Neurol 2008; 7: 354–61.
 Stovner L, Hagen K, Jensen R, et al. The global burden of headache: a documentation of headache prevalence and disability worldwide. Cephalalgia 2007; 27: 193–210.
 EUROLIGHT; key project document.
How many types exist?
Cluster headache (CH) is the most common of the trigeminal autonomic cephalal- gias (TACs) . CH is a strictly lateralized and devastating periorbital headache, characterized with a very severe, excruciating pain and the presence of ipsilateral cranial autonomic symptoms, such as conjunctival injection, lacrimation and rhi- norrhea. Lifetime prevalence is 1/1000 and a progressive reduction of the male/ female ratio over the past decades has been demonstrated and is now 2.1:1 . The peculiar timing over the day (1 – 8 attacks), in the entire active cluster period lasting 60 – 90 days, and in the span of the year particularly with the seasonal changes, renders this headache unique, very easy to diagnose and differentiate from other TACs. Nevertheless, only 1/3 of these patients received the diagnosis of CH, with a diagnostic delay of 5.3 years and more than 2/3 of them never received any treatment.
–Martelletti P. Cluster headache management and beyond. Expert Opin Pharmacother. 2015;16:1411-5
- Chronic migraine is a clearly defined subtype of migraine affecting between 1-2% of the general population, yet it receives little attention.
- Chronic migraine usually develops from episodic migraine at a conversion rate of about 3% a year; the chronification is reversible
- Risk factors for migraine chronification include overuse of acute migraine medication, ineffective acute treatment, obesity, depression, low educational status and stressful life events.
–May A, Schulte LH. Chronic migraine: risk factors, mechanisms and treatment. Nat Rev Neurol. 2016;12:455-64
The prevalence of trigeminal neuralgia in the population is 0.07%, compared to approximately 2% in patients with facial pain in general.
Conversely, trigeminal neuralgia (also known as tic douloureux) is frequently mistaken for dental pain, leading to redundant diagnostic procedures such as x-rays of the jaw and, in more than a few cases, unnecessary extractions of teeth.
Accurate diagnosis of trigeminal neuralgia depends critically on the patient’s description of its characteristic features. Clarification of the characteristics of the pain is, therefore, necessary to guide clinical diagnosis and management. Successful diagnostic criteria must account for established variants of the phenotype (eg, typical versus atypical trigeminal neuralgia), incorporate symptoms or signs that correlate with different etiologies (primary trigeminal neuralgia versus trigeminal neuralgia secondary to a major neurologic disease), and identify pain features that indicate underlying pathophysiologic mechanisms (peripheral ver- sus central), as they are relevant to direct further investigations or treatment de- decisions (pharmacologic therapy versus surgery).
–Cruccu G. Trigeminal Neuralgia. Continuum (Minneap Minn). 2017;23:396-420
Tension-type headache has distinct subtypes. Episodic tension-type headache, like migraine, occurs in attack-like episodes. These usually last no more than a few hours but can persist for several days. Chronic tension-type headache, one of the chronic daily headache syndromes, is present most of the time and can be unremitting over long periods. It is less common, but much more disabling to those affected.
Headache, in either case, is usually mild or moderate and generalized, though it can be one-sided. It is described as pressure or tightness, like a band around the head, sometimes spreading into or from the neck. It lacks the specific features and associated symptoms of migraine.
–Paolo Martelletti, Timothy J. Steiner (eds.), Handbook of Headache, Springer Milan Heidelberg Dordrecht London New York, 2011
Migraine is a primary headache disorder, probably with a genetic basis. Activation of a mechanism deep in the brain causes release of pain-producing inflammatory substances around the nerves and blood vessels of the head. Why this happens periodically and what brings the process to an end in spontaneous resolution of attacks are uncertain.
Usually starting at puberty, migraine is recurrent throughout life in many cases. Adults with a migraine describe episodic attacks with specific features, of which headache and nausea are the most characteristic. In children, attacks tend to be shorter-lasting and abdominal symptoms more prominent. Attack frequency is typically one or twice a month but can be anywhere between once a year and once a week, often subject to lifestyle and environmental factors.
Paolo Martelletti, Timothy J. Steiner (eds.), Handbook of Headache, Springer Milan Heidelberg Dordrecht London New York, 2011