Curr Neurol Neurosci Rep (2015) 15:4 DOI 10.1007/s11910-015-0528-2
HEADACHE (RB HALKER, SECTION EDITOR)
Approach to Chronic Daily Headache Huma U. Sheikh
# Springer Science+Business Media New York 2015
Abstract Chronic daily headaches (CDH) is a descriptive term used for patients who experience headaches on at least 15 days or more out of the month; for at least 3 months, irrespective of the underlying headache etiology. It is a syndrome that affects many people, usually with an underlying primary headache disorder, leading to a reduction in quality of life. The two most common underlying primary headaches are migraines and tension-type headaches. The prevalence is about 4 %, and research is emerging on risk factors and comorbidities. The first step when approaching a patient with chronic daily headaches is to rule out secondary causes. Once that is done, the goal is to effectively reduce the days of headache through preventive treatment as well as complementary therapies. This also often involves limiting the use of abortive therapy to avoid medication-overuse headaches (MOH). The pathophysiology, although not fully understood, is thought to be related to central sensitization along with Bneurogenic inflammation.^ Chronic daily headaches can be difficult to treat and at times require a tertiary specialized center. Keywords Chronic daily headache . Chronic migraine . Medication-overuse headache . Abortive . New daily persistent headache . Chronic tension-type headaches
Introduction The patient below in the presentation is a common scenario seen in a specialty headache clinic. It is a good patient to keep
in mind when deciding on how to approach a similar patient. It also demonstrates many salient features of the descriptive term known as a Bchronic daily headaches (CDH)^ [1•, 2•]. This is not a diagnostic term, as there is no definition of this in the latest International Classification of Headache Disorders, 3rd beta edition. However, it is often used as a way to describe a disorder where a headache occurs on at least 15 days or more of the month for at least 3 months, irrespective of the underlying headache etiology [2•]. The approach to a patient with chronic daily headache should be systematic and thoughtful.
Patient Presentation A 35-year-old woman with history of depression and migraine presents for evaluation in a specialty headache clinic. She was given a diagnosis of migraines at age 19, initially with headaches occurring mostly around the time of her menstrual cycles. However, in the last year, she notes that her headaches have now increased to daily. On most days, she will awake with a mild headache that waxes and wanes throughout the day, sometimes reaching a 8–9/10. When severe, she can have severe nausea and photophobia, although her daily mild headaches do not have those features. She has had to call out of from work three times in the last month, with one emergency room visit. She has previously tried a couple of preventives, which she did not find helpful. Currently, she is treating with daily Excedrin or Motrin, reserving her sumatriptan for her most severe headaches. She is also taking paroxetine along with her birth control pill.
This article is a part of the Topical Collection on Headache H. U. Sheikh (*) Department of Neurology, Brigham and Women’s Hospital, Harvard Medical School, 1153 Centre Street, Suite 4970, Boston, MA 02130, USA e-mail: [email protected]
Epidemiology The prevalence of chronic daily headache is believed to be in the range of 3–5 % [2•, 3, 4•]. The impact of having a
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headache on most days of the month can lead to impairment in daily functioning, along with reduction in quality of life as well as economic impacts on society [4•, 5, 6]. Chronic daily headaches have a significant impact on society, mainly through absenteeism and decreased productivity [7]. It is found that those with chronic daily headaches tend to have a high rate of some psychiatric comorbidities, including depression, anxiety, and post-traumatic stress disorder (PTSD) [8]. In some studies, depression and anxiety are present at a rate of almost two times more in those with chronic migraine compared with those with episodic migraine, a common underlying cause of chronic daily headaches [2•, 9, 10]. Some studies note that PTSD is present in 30–43 % of patients with chronic migraine and 19 % of those with chronic daily headache [11, 12]. A history of concussion is also emerging as a comorbid condition in patients with CDH, although this requires further study to elucidate [2•]. There is also high correlation with substance abuse disorders [4•, 13, 14]. Some of the risk factors that are thought to increase the development of chronic daily headaches include snoring, high use of caffeine, smoking, and obesity [15–17]. A study by Scher et al. described the factors that were thought to be important in the progression of episodic migraines to chronic migraines, which can predispose someone to develop chronic daily headaches. These risk factors include, among others, Bmedication overuse, increasing headache frequency and long duration of illness^ [15].
Evaluation As with any progressive or difficult headache, the alert clinician should be on the outlook for secondary causes. A firsttime presentation for daily headaches needs to be complete and thorough. A thorough investigation includes a full history, complete physical examination, including a complete fundoscopic exam, along with some form of imaging, usually a MRI of the brain [1•]. Depending on features of the headache and possible associated features, further studies including vascular imaging or a lumbar puncture may be warranted. At times, it may also be helpful to use objective criteria including headache diaries to get a better idea of the actual days of headache and use of abortive and preventive medications [2•]. Some important secondary causes of persistent headaches need to be ruled out before diagnosing a patient with a primary headache syndrome. Some common disorders that can present as persistent headaches include disorders of intracranial pressure, structural lesions, and vascular and infectious causes, including vasculitis or other vascular lesions, i.e., arteriovenous malformations or aneurysms. Secondary causes should be ruled out in cases where new headaches develop in a patient with no previous history of headaches or a change in the pattern of a patient with previous primary headaches. One
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important cause of secondary headaches that is regarded as an important cause of worsening of headaches includes medication overuse. Although not always regarded as a secondary cause, it presents most often in patients with a preexisting headache disorder. Once secondary causes are ruled out, the focus turns to treating the chronic daily headache syndrome. This is usually based on the underlying headache diagnosis, usually a primary headache. The two most common underlying primary headaches that constitute CDH are chronic migraine and chronic tension-type headaches [18–21]. According to the Global Burden of Disease, migraine and tension-type headaches are extremely disabling given how prevalent they are [22]. Other less common causes of a chronic headache include cluster headaches, hemicrania continua (HC), new daily persistent headaches (NDPH), and medication-overuse headache (MOH). MOH is sometimes thought to be a Bsecondary form,^ but is discussed because it is thought to be a very important cause of the development of daily headaches. Some studies show that up to 70 % of people may be using abortive therapy very frequently, daily in a majority of cases [22]. Some authors will break up the underlying causes of chronic daily headaches into long- and short-duration headaches, based on the duration of the headaches, either shorter or longer than 4 hours. The short-duration headaches include chronic cluster headaches [1•]. Cluster headaches are considered chronic if they Boccur for more than a year, with remissions of headaches for less than 1 month at a time [23].^ Hypnic headache is also in the differential. The long-duration CDH include chronic migraine (CM), chronic tension-type headaches (CTTH), along with NDPH and hemicrania continua [1•, 23]. Short-Duration Headaches Cluster headache is in the category of trigeminal autonomic cephalgias (TAC). The pain is usually described as severe unilateral, orbital, supraorbital, and/or temporal pain lasting 15–180 minutes (when untreated) with at least one autonomic symptom, including conjunctival injection and/or lacrimation, nasal congestion and/or rhinorrhoea, eyelid oedema, forehead and facial sweating, forehead and facial flushing, sensation of fullness in the ear, miosis and/or ptosis, along with a sense of restlessness or agitation. The attacks usually occur daily, up to eight times a day for weeks or months separated by remission periods that can last from months to years. Cluster headaches are termed chronic when they occur for more than a year or remission periods are less than 1 month. It can develop from episodic headache or de novo [23]. Other short-duration headaches include hypnic headache and other TACs, including short-lasting unilateral neuralgiform headaches with conjunctival injection and tearing (SUNCT). However, there is not much information regarding their abilities to develop into chronic daily headaches.
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The treatment of cluster headaches includes starting a preventive; verapamil and lithium have the best evidence regarding efficacy. While these take effect, patients may be bridged with steroids. Options for abortive therapy include sumatriptan, which works best when given intramuscularly, as well as oxygen using a face mask. There does not seem to be risk of medication overuse with triptans when the underlying primary headache is cluster headaches, unlike in migraines. Long-Duration Headaches The long-duration headaches are more likely to develop into chronic daily headache patterns. The biggest subtype is chronic migraine; up to 50 % of patients with chronic daily headache on evaluation are found to have chronic migraines, while chronic tension-type headaches are the other largest component [19, 24]. However, a study conducted by Silberstein et al. consisting of 150 patients with chronic daily headache found that almost half of patients could not be classified according to the current IHS-2 criteria. They proposed a new classification with four subtypes, under which most patients were thought to fit into the chronic migraine category. A fewer number of patients would be categorized as having tension-type headache, new daily persistent headaches (NDPH), or hemicrania continua [25]. It is not clear whether the development of a chronic daily headache constitutes a new entity or is a variation of the same pathological process as the original headache disorder.
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syndrome. Some studies estimate that up to 75 % of chronic migraine patients revert back to episodic after treatment of medication-overuse headaches [4•].
Pathophysiology Although the development of chronic daily headaches is largely dependent on the underlying headache diagnosis, there are likely similar underlying factors involving all headaches that become continuous. Especially in the development of medicationoveruse headaches, there is thought to be facilitation of trigeminal and somatic nociceptive systems at the supraspinal level [30, 31]. Central sensitization is thought to be an important component, also thought to be involved in the chronification of migraines. This is also thought to be an important component of the development of chronic migraines from episodic migraines, along with Bneurogenic inflammation^ and persistent activation of the trigeminovascular system [4•, 32, 33]. Other proposed mechanisms for CDH are Bexcitation of peripheral afferent fibers from repetitive peripheral input,^ as well as Benhanced responsiveness of nucleus caudalis neurons^ [4•]. These are all thought to be changes in the nervous system from repeated attacks of episodic headaches or migraines. There is likely also a genetic predisposition. Newer mechanisms that are being looked into include the role of low serotonin with receptor upregulation, NMDA receptor dysfunction, and low beta endorphin levels [4•].
Chronic Migraine An important cause of CDH is Brefractory chronic migraine^ [26]. Chronic migraine is defined by ICHD-3 beta as headaches on at least 15 days of the month, where at least eight of those headaches fulfill criteria for migraine. This can also be referenced as transformed migraine, when the frequency of headaches increases from episodic to chronic with an underlying migraine pathology [23]. Refractory and intractable migraines are used interchangeably and can be thought of a headache that does not respond to at least Bfour classes of preventives^ [27]. One study found that most of those with chronic daily headaches have features that are consistent with migraines [28]. A special interest section of the American Headache Society (AHS) proposed that refractory migraine be referred to a headache disorder where at least three preventives, in the correct doses for an appropriate amount of time, have been tried without adequate relief. This diagnosis can be made after medication overuse headaches have been ruled out, in addition to other secondary causes., [26]. Studies indicate that the prevalence of chronic migraine is about 2 % [4•]. It is estimated that somewhere between 3 and 14 % of episodic migraines convert to either chronic migraine or daily headache yearly [4•, 17, 29]. An important contributor to chronic headaches is thought to be the overuse of abortives or medication overuse that can complicate a primary headache
Treatment When chronic migraine progresses to a chronic daily headache, it can be very difficult to treat [1•]. It requires a multidisciplinary approach including pharmacological and nonpharmacological or complementary therapies. It is thought that those with chronic daily headache have a hypersensitive central nervous system [4•]. Much of the approach to treating chronic daily headache involves a multifaceted and multidisciplinary approach, including pharmacological therapy, psychological therapy including biofeedback, and education and lifestyle medicine [34]. Therefore, it is important to avoid changes in their normal routines that can upset their sensitive systems. As for all patients who are prone to headaches, it is important to avoid common known triggers. They should remember to stay hydrated and avoid skipping meals. It is important to keep consistent sleeping patterns, since adequate, regular sleep is vital to preventing headaches. If there is suspicion for insomnia or sleep apnea, these should be further evaluated. It is also important to keep up with regular exercise and actively work on stress management, including complementary techniques, like meditation or yoga [2•]. Recently, Amoils et al. described a case report using integrative
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approach to treating CDH, involving a five-step program. This involves Bexpanded CM^ treatments, treatment for stress, a nutritional evaluation, hormonal treatment, and assessment and treatment of structural and bioenergic imbalances [34]. Another recent study looked at the use of cognitive behavioral therapy in adolescents with chronic daily headaches. This was in an attempt to bridge the gap in the treatment of young adults with daily headaches [35]. In this study, patients who were randomized to the group where they learned coping skills fared better overall. Pharmacological treatment for chronic migraines involves starting with a migraine preventive. The top migraine preventives with the most evidence regarding efficacy include topiramate, propranolol, amitriptyline, valproate acid, and onabotulinum-A, the last of which is the only one that is FDA approved for chronic migraine. Other commonly used first-line agents include venlafaxine and herbal or vitamin supplements including magnesium, riboflavin, and feverfew. Herbal supplements have been studied in episodic migraine but may be tried in chronic migraine as well [36]. It is also important to remind patients that they should have a Bstep care^ approach to treating with abortives, so as to avoid overuse [36–38]. They should be cautioned to attempt to only use abortives on 1 to 2 days a week. It is also important to treat comorbidities that could be impeding the treatment of the headaches, including psychological and sleep disorders.
Medication-Overuse Headaches Medication-overuse headaches (MOH) can be seen as a Bsecondary form^ of CDH, caused by excessive use of abortive medications [2•]. MOH—also known as rebound or Banalgesicdependent headache^—is thought to develop from the overuse of analgesics, opioids, ergotamines, or triptans which can increase the headache frequency over time. One sign of MOH may be that patients awaken in the morning or overnight with headache. Over time, the headache may lose some of its original features, including migrainous features, when it becomes more chronic. Over time, escalating doses of abortives are required and analgesics are no longer as effective [1•]. Recently, some studies have shown that topiramate is helpful in the treatment of chronic daily headache [2•]. Medication-overuse headaches (MOH) are thought to be a big contributor to the development of chronicity of headaches. Frequent use of pain medications can lead to worsening of headaches, which may become a never-cycle of worsening pain, more use of pain medications and disability [22, 39]. Some studies show that both chronic migraine and medication-overuse headaches are associated with a lower socioeconomic status. A recent study in the Journal of Pain evaluated the associations of socioeconomic position in patients with chronic headache, further subdivided into those with and without medication-overuse headache [22]. It included
Curr Neurol Neurosci Rep (2015) 15:4
over a hundred thousand patients included in the Danish National Health Survey, which found that a little over half of patients with chronic headache also had a significant medication overuse. Those in lower socioeconomic status were also more likely to have chronic headaches [22]. During the weaning of the abortives that are thought to be the cause of the MOH, it may be necessary to closely monitor patients, including in an infusion clinic or as an inpatient. During this time, certain protocols may help them while detoxing from abortives. This is due to the fact that while weaning, patients may experience transient worsening of their headaches. Opioids, butalbital-containing analgesics, and aspirin/acetaminophen/caffeine combinations have the highest risk for onset of medication-overuse headaches [40]. Although different studies vary, even as low as around 5 days out of the month of use of a high-risk agent, including a barbiturate was enough to bring on MOH. Triptans are thought to be of moderate risk and NSAIDs are low, therefore requiring more frequent use, closer to 10–14 days out of the month to cause rebound headaches, although this can vary in the individual patient [41].
Chronic Tension-Type Headaches Chronic tension-type headache is usually described as a low to moderate grade daily headache on more than 15 days a month without any migrainous features. Most patients describe it as a band around his/her head [23]. It is another major primary headache that can be the underlying headache with chronic daily headaches. It is usually treated with similar preventives as migraine; usually tricyclic antidepressants are tried as first line. There is some evidence that tricyclic antidepressants with cognitive behavioral therapy is useful [1•].
Other Long-Duration Headaches Hemicrania continua is described as Bcontinuous sidelocked unilateral^ with cranial autonomic symptoms [1•, 23]. Although it can be a cause of a chronic daily headache, it is usually treated successfully with indomethacin. Resolution of the headache with indomethacin is regarded to be diagnostic of this headache type [22, 23]. New daily persistent headache is a headache that is continuous from day of onset. A unique feature is that most patients will remember the exact date of onset. It occurs slightly more in women [4•]. Most often patients will describe the headache as a Bbilateral pressure or tightening,^ sometimes with migrainous features. NDPH is usually regarded as one of the few headache syndromes that is persistently refractory to medications [23]. Studies estimate that about 10 % of patients with CDH are diagnosed with NDPH [19].
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Conclusion
12.
Chronic daily headaches can present as a complex and difficult-to-treat phenomenon. However, with a systematic approach, there can be ways to sort out the cause of the daily headache. Once secondary causes are ruled out, most CDH will have an underlying headache disorder that will guide treatment.
13. 14.
15. 16.
Compliance with Ethics Guidelines Conflict of Interest Huma U. Sheikh declares no conflict of interest. Human and Animal Rights and Informed Consent This article does not contain any studies with human or animal subjects performed by any of the authors.
17.
18. 19.
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Sarchielli P, Alberti A, Floridi A, Gallai V. Levels of nerve growth factor in cerebrospinal fluid of chronic daily headache patients. Neurology. 2001;57(1):132–4. 33. Schwedt TJ, Dodick DW. Advanced neuroimaging of migraine. Lancet Neurol. 2009;8(6):560–8. 34. Amoils S, Amoils S, Lester T, Woolford L, Gallagher L. The positive impact of integrative medicine in the treatment of recalcitrant chronic daily headache: a series of case reports. Glob Adv Health Med. 2014;3(4):45–54. 35. Hickman C, Jacobson D, Melnyk BM. Randomized controlled trial of the acceptability, feasibility, and preliminary effects of a cognitive behavioral skills building intervention in adolescents with chronic daily headaches: a pilot study. J Pediatr Health Care. 2014;29(1):5–16. 36. Lipton RB, Bigal ME, Diamond M, Freitag F, Reed ML, Stewart WF, et al. Migraine prevalence, disease burden, and the need for preventive therapy. Neurology. 2007;68(5):343–9.
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Lipton RB, Bigal ME, Diamond M, AMPP Advisory Group, et al. Migraine prevalence, disease burden, and the need for preventive therapy. Neurology. 2007;68:343–9. 38. Lipton RB, Stewart WF, Stone AM, Lainez MJ, Sawyer JP. Disability in strategies of care study group. Stratified care vs step care strategies for migraine: the Disability in Strategies of Care (DISC) study: a randomized trial. JAMA. 2000;284(20): 2599–605. 39. Hagen K, Linde M, Steiner TJ, Stovner LJ, Zwart JA. Risk factors for medication-overuse headache: an 11-year followup study. The Nord-Trondelag Health Studies. Pain. 2012;153(1): 56–61. 40. Smith TR, Stoneman J. Medication overuse headache from antimigraine therapy: clinical features, pathogenesis and management. Drugs. 2004;64(22):2503–14. 41. Bigal ME, Lipton RB. Excessive acute migraine medication use and migraine progression. Neurology. 2008;71(22):1821–8.
HEADACHE (RB HALKER, SECTION EDITOR)
Approach to Chronic Daily Headache Huma U. Sheikh
# Springer Science+Business Media New York 2015
Abstract Chronic daily headaches (CDH) is a descriptive term used for patients who experience headaches on at least 15 days or more out of the month; for at least 3 months, irrespective of the underlying headache etiology. It is a syndrome that affects many people, usually with an underlying primary headache disorder, leading to a reduction in quality of life. The two most common underlying primary headaches are migraines and tension-type headaches. The prevalence is about 4 %, and research is emerging on risk factors and comorbidities. The first step when approaching a patient with chronic daily headaches is to rule out secondary causes. Once that is done, the goal is to effectively reduce the days of headache through preventive treatment as well as complementary therapies. This also often involves limiting the use of abortive therapy to avoid medication-overuse headaches (MOH). The pathophysiology, although not fully understood, is thought to be related to central sensitization along with Bneurogenic inflammation.^ Chronic daily headaches can be difficult to treat and at times require a tertiary specialized center. Keywords Chronic daily headache . Chronic migraine . Medication-overuse headache . Abortive . New daily persistent headache . Chronic tension-type headaches
Introduction The patient below in the presentation is a common scenario seen in a specialty headache clinic. It is a good patient to keep
in mind when deciding on how to approach a similar patient. It also demonstrates many salient features of the descriptive term known as a Bchronic daily headaches (CDH)^ [1•, 2•]. This is not a diagnostic term, as there is no definition of this in the latest International Classification of Headache Disorders, 3rd beta edition. However, it is often used as a way to describe a disorder where a headache occurs on at least 15 days or more of the month for at least 3 months, irrespective of the underlying headache etiology [2•]. The approach to a patient with chronic daily headache should be systematic and thoughtful.
Patient Presentation A 35-year-old woman with history of depression and migraine presents for evaluation in a specialty headache clinic. She was given a diagnosis of migraines at age 19, initially with headaches occurring mostly around the time of her menstrual cycles. However, in the last year, she notes that her headaches have now increased to daily. On most days, she will awake with a mild headache that waxes and wanes throughout the day, sometimes reaching a 8–9/10. When severe, she can have severe nausea and photophobia, although her daily mild headaches do not have those features. She has had to call out of from work three times in the last month, with one emergency room visit. She has previously tried a couple of preventives, which she did not find helpful. Currently, she is treating with daily Excedrin or Motrin, reserving her sumatriptan for her most severe headaches. She is also taking paroxetine along with her birth control pill.
This article is a part of the Topical Collection on Headache H. U. Sheikh (*) Department of Neurology, Brigham and Women’s Hospital, Harvard Medical School, 1153 Centre Street, Suite 4970, Boston, MA 02130, USA e-mail: [email protected]
Epidemiology The prevalence of chronic daily headache is believed to be in the range of 3–5 % [2•, 3, 4•]. The impact of having a
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headache on most days of the month can lead to impairment in daily functioning, along with reduction in quality of life as well as economic impacts on society [4•, 5, 6]. Chronic daily headaches have a significant impact on society, mainly through absenteeism and decreased productivity [7]. It is found that those with chronic daily headaches tend to have a high rate of some psychiatric comorbidities, including depression, anxiety, and post-traumatic stress disorder (PTSD) [8]. In some studies, depression and anxiety are present at a rate of almost two times more in those with chronic migraine compared with those with episodic migraine, a common underlying cause of chronic daily headaches [2•, 9, 10]. Some studies note that PTSD is present in 30–43 % of patients with chronic migraine and 19 % of those with chronic daily headache [11, 12]. A history of concussion is also emerging as a comorbid condition in patients with CDH, although this requires further study to elucidate [2•]. There is also high correlation with substance abuse disorders [4•, 13, 14]. Some of the risk factors that are thought to increase the development of chronic daily headaches include snoring, high use of caffeine, smoking, and obesity [15–17]. A study by Scher et al. described the factors that were thought to be important in the progression of episodic migraines to chronic migraines, which can predispose someone to develop chronic daily headaches. These risk factors include, among others, Bmedication overuse, increasing headache frequency and long duration of illness^ [15].
Evaluation As with any progressive or difficult headache, the alert clinician should be on the outlook for secondary causes. A firsttime presentation for daily headaches needs to be complete and thorough. A thorough investigation includes a full history, complete physical examination, including a complete fundoscopic exam, along with some form of imaging, usually a MRI of the brain [1•]. Depending on features of the headache and possible associated features, further studies including vascular imaging or a lumbar puncture may be warranted. At times, it may also be helpful to use objective criteria including headache diaries to get a better idea of the actual days of headache and use of abortive and preventive medications [2•]. Some important secondary causes of persistent headaches need to be ruled out before diagnosing a patient with a primary headache syndrome. Some common disorders that can present as persistent headaches include disorders of intracranial pressure, structural lesions, and vascular and infectious causes, including vasculitis or other vascular lesions, i.e., arteriovenous malformations or aneurysms. Secondary causes should be ruled out in cases where new headaches develop in a patient with no previous history of headaches or a change in the pattern of a patient with previous primary headaches. One
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important cause of secondary headaches that is regarded as an important cause of worsening of headaches includes medication overuse. Although not always regarded as a secondary cause, it presents most often in patients with a preexisting headache disorder. Once secondary causes are ruled out, the focus turns to treating the chronic daily headache syndrome. This is usually based on the underlying headache diagnosis, usually a primary headache. The two most common underlying primary headaches that constitute CDH are chronic migraine and chronic tension-type headaches [18–21]. According to the Global Burden of Disease, migraine and tension-type headaches are extremely disabling given how prevalent they are [22]. Other less common causes of a chronic headache include cluster headaches, hemicrania continua (HC), new daily persistent headaches (NDPH), and medication-overuse headache (MOH). MOH is sometimes thought to be a Bsecondary form,^ but is discussed because it is thought to be a very important cause of the development of daily headaches. Some studies show that up to 70 % of people may be using abortive therapy very frequently, daily in a majority of cases [22]. Some authors will break up the underlying causes of chronic daily headaches into long- and short-duration headaches, based on the duration of the headaches, either shorter or longer than 4 hours. The short-duration headaches include chronic cluster headaches [1•]. Cluster headaches are considered chronic if they Boccur for more than a year, with remissions of headaches for less than 1 month at a time [23].^ Hypnic headache is also in the differential. The long-duration CDH include chronic migraine (CM), chronic tension-type headaches (CTTH), along with NDPH and hemicrania continua [1•, 23]. Short-Duration Headaches Cluster headache is in the category of trigeminal autonomic cephalgias (TAC). The pain is usually described as severe unilateral, orbital, supraorbital, and/or temporal pain lasting 15–180 minutes (when untreated) with at least one autonomic symptom, including conjunctival injection and/or lacrimation, nasal congestion and/or rhinorrhoea, eyelid oedema, forehead and facial sweating, forehead and facial flushing, sensation of fullness in the ear, miosis and/or ptosis, along with a sense of restlessness or agitation. The attacks usually occur daily, up to eight times a day for weeks or months separated by remission periods that can last from months to years. Cluster headaches are termed chronic when they occur for more than a year or remission periods are less than 1 month. It can develop from episodic headache or de novo [23]. Other short-duration headaches include hypnic headache and other TACs, including short-lasting unilateral neuralgiform headaches with conjunctival injection and tearing (SUNCT). However, there is not much information regarding their abilities to develop into chronic daily headaches.
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The treatment of cluster headaches includes starting a preventive; verapamil and lithium have the best evidence regarding efficacy. While these take effect, patients may be bridged with steroids. Options for abortive therapy include sumatriptan, which works best when given intramuscularly, as well as oxygen using a face mask. There does not seem to be risk of medication overuse with triptans when the underlying primary headache is cluster headaches, unlike in migraines. Long-Duration Headaches The long-duration headaches are more likely to develop into chronic daily headache patterns. The biggest subtype is chronic migraine; up to 50 % of patients with chronic daily headache on evaluation are found to have chronic migraines, while chronic tension-type headaches are the other largest component [19, 24]. However, a study conducted by Silberstein et al. consisting of 150 patients with chronic daily headache found that almost half of patients could not be classified according to the current IHS-2 criteria. They proposed a new classification with four subtypes, under which most patients were thought to fit into the chronic migraine category. A fewer number of patients would be categorized as having tension-type headache, new daily persistent headaches (NDPH), or hemicrania continua [25]. It is not clear whether the development of a chronic daily headache constitutes a new entity or is a variation of the same pathological process as the original headache disorder.
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syndrome. Some studies estimate that up to 75 % of chronic migraine patients revert back to episodic after treatment of medication-overuse headaches [4•].
Pathophysiology Although the development of chronic daily headaches is largely dependent on the underlying headache diagnosis, there are likely similar underlying factors involving all headaches that become continuous. Especially in the development of medicationoveruse headaches, there is thought to be facilitation of trigeminal and somatic nociceptive systems at the supraspinal level [30, 31]. Central sensitization is thought to be an important component, also thought to be involved in the chronification of migraines. This is also thought to be an important component of the development of chronic migraines from episodic migraines, along with Bneurogenic inflammation^ and persistent activation of the trigeminovascular system [4•, 32, 33]. Other proposed mechanisms for CDH are Bexcitation of peripheral afferent fibers from repetitive peripheral input,^ as well as Benhanced responsiveness of nucleus caudalis neurons^ [4•]. These are all thought to be changes in the nervous system from repeated attacks of episodic headaches or migraines. There is likely also a genetic predisposition. Newer mechanisms that are being looked into include the role of low serotonin with receptor upregulation, NMDA receptor dysfunction, and low beta endorphin levels [4•].
Chronic Migraine An important cause of CDH is Brefractory chronic migraine^ [26]. Chronic migraine is defined by ICHD-3 beta as headaches on at least 15 days of the month, where at least eight of those headaches fulfill criteria for migraine. This can also be referenced as transformed migraine, when the frequency of headaches increases from episodic to chronic with an underlying migraine pathology [23]. Refractory and intractable migraines are used interchangeably and can be thought of a headache that does not respond to at least Bfour classes of preventives^ [27]. One study found that most of those with chronic daily headaches have features that are consistent with migraines [28]. A special interest section of the American Headache Society (AHS) proposed that refractory migraine be referred to a headache disorder where at least three preventives, in the correct doses for an appropriate amount of time, have been tried without adequate relief. This diagnosis can be made after medication overuse headaches have been ruled out, in addition to other secondary causes., [26]. Studies indicate that the prevalence of chronic migraine is about 2 % [4•]. It is estimated that somewhere between 3 and 14 % of episodic migraines convert to either chronic migraine or daily headache yearly [4•, 17, 29]. An important contributor to chronic headaches is thought to be the overuse of abortives or medication overuse that can complicate a primary headache
Treatment When chronic migraine progresses to a chronic daily headache, it can be very difficult to treat [1•]. It requires a multidisciplinary approach including pharmacological and nonpharmacological or complementary therapies. It is thought that those with chronic daily headache have a hypersensitive central nervous system [4•]. Much of the approach to treating chronic daily headache involves a multifaceted and multidisciplinary approach, including pharmacological therapy, psychological therapy including biofeedback, and education and lifestyle medicine [34]. Therefore, it is important to avoid changes in their normal routines that can upset their sensitive systems. As for all patients who are prone to headaches, it is important to avoid common known triggers. They should remember to stay hydrated and avoid skipping meals. It is important to keep consistent sleeping patterns, since adequate, regular sleep is vital to preventing headaches. If there is suspicion for insomnia or sleep apnea, these should be further evaluated. It is also important to keep up with regular exercise and actively work on stress management, including complementary techniques, like meditation or yoga [2•]. Recently, Amoils et al. described a case report using integrative
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approach to treating CDH, involving a five-step program. This involves Bexpanded CM^ treatments, treatment for stress, a nutritional evaluation, hormonal treatment, and assessment and treatment of structural and bioenergic imbalances [34]. Another recent study looked at the use of cognitive behavioral therapy in adolescents with chronic daily headaches. This was in an attempt to bridge the gap in the treatment of young adults with daily headaches [35]. In this study, patients who were randomized to the group where they learned coping skills fared better overall. Pharmacological treatment for chronic migraines involves starting with a migraine preventive. The top migraine preventives with the most evidence regarding efficacy include topiramate, propranolol, amitriptyline, valproate acid, and onabotulinum-A, the last of which is the only one that is FDA approved for chronic migraine. Other commonly used first-line agents include venlafaxine and herbal or vitamin supplements including magnesium, riboflavin, and feverfew. Herbal supplements have been studied in episodic migraine but may be tried in chronic migraine as well [36]. It is also important to remind patients that they should have a Bstep care^ approach to treating with abortives, so as to avoid overuse [36–38]. They should be cautioned to attempt to only use abortives on 1 to 2 days a week. It is also important to treat comorbidities that could be impeding the treatment of the headaches, including psychological and sleep disorders.
Medication-Overuse Headaches Medication-overuse headaches (MOH) can be seen as a Bsecondary form^ of CDH, caused by excessive use of abortive medications [2•]. MOH—also known as rebound or Banalgesicdependent headache^—is thought to develop from the overuse of analgesics, opioids, ergotamines, or triptans which can increase the headache frequency over time. One sign of MOH may be that patients awaken in the morning or overnight with headache. Over time, the headache may lose some of its original features, including migrainous features, when it becomes more chronic. Over time, escalating doses of abortives are required and analgesics are no longer as effective [1•]. Recently, some studies have shown that topiramate is helpful in the treatment of chronic daily headache [2•]. Medication-overuse headaches (MOH) are thought to be a big contributor to the development of chronicity of headaches. Frequent use of pain medications can lead to worsening of headaches, which may become a never-cycle of worsening pain, more use of pain medications and disability [22, 39]. Some studies show that both chronic migraine and medication-overuse headaches are associated with a lower socioeconomic status. A recent study in the Journal of Pain evaluated the associations of socioeconomic position in patients with chronic headache, further subdivided into those with and without medication-overuse headache [22]. It included
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over a hundred thousand patients included in the Danish National Health Survey, which found that a little over half of patients with chronic headache also had a significant medication overuse. Those in lower socioeconomic status were also more likely to have chronic headaches [22]. During the weaning of the abortives that are thought to be the cause of the MOH, it may be necessary to closely monitor patients, including in an infusion clinic or as an inpatient. During this time, certain protocols may help them while detoxing from abortives. This is due to the fact that while weaning, patients may experience transient worsening of their headaches. Opioids, butalbital-containing analgesics, and aspirin/acetaminophen/caffeine combinations have the highest risk for onset of medication-overuse headaches [40]. Although different studies vary, even as low as around 5 days out of the month of use of a high-risk agent, including a barbiturate was enough to bring on MOH. Triptans are thought to be of moderate risk and NSAIDs are low, therefore requiring more frequent use, closer to 10–14 days out of the month to cause rebound headaches, although this can vary in the individual patient [41].
Chronic Tension-Type Headaches Chronic tension-type headache is usually described as a low to moderate grade daily headache on more than 15 days a month without any migrainous features. Most patients describe it as a band around his/her head [23]. It is another major primary headache that can be the underlying headache with chronic daily headaches. It is usually treated with similar preventives as migraine; usually tricyclic antidepressants are tried as first line. There is some evidence that tricyclic antidepressants with cognitive behavioral therapy is useful [1•].
Other Long-Duration Headaches Hemicrania continua is described as Bcontinuous sidelocked unilateral^ with cranial autonomic symptoms [1•, 23]. Although it can be a cause of a chronic daily headache, it is usually treated successfully with indomethacin. Resolution of the headache with indomethacin is regarded to be diagnostic of this headache type [22, 23]. New daily persistent headache is a headache that is continuous from day of onset. A unique feature is that most patients will remember the exact date of onset. It occurs slightly more in women [4•]. Most often patients will describe the headache as a Bbilateral pressure or tightening,^ sometimes with migrainous features. NDPH is usually regarded as one of the few headache syndromes that is persistently refractory to medications [23]. Studies estimate that about 10 % of patients with CDH are diagnosed with NDPH [19].
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Conclusion
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Chronic daily headaches can present as a complex and difficult-to-treat phenomenon. However, with a systematic approach, there can be ways to sort out the cause of the daily headache. Once secondary causes are ruled out, most CDH will have an underlying headache disorder that will guide treatment.
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Compliance with Ethics Guidelines Conflict of Interest Huma U. Sheikh declares no conflict of interest. Human and Animal Rights and Informed Consent This article does not contain any studies with human or animal subjects performed by any of the authors.
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18. 19.
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