1. Epidemiology of migraine pain
Welcome to this presentation in the series “Know Migraine Pain”. In this module we will review the epidemiology of migraine pain.

2. WHAT IS MIGRAINE?
In this first section we’ll discuss the question “What is Migraine?”.

3. Headache Disorders
Among the most common disorders of the nervous system1
Prevalence among adults (symptomatic at least once within the last year) is almost 47% worldwide1
Associated with personal and societal burdens of pain, disability, reduced quality of life, and financial burden1
Globally, only a minority of people with headache disorders are appropriately diagnosed by a health care provider1
Headache has been underestimated, under-recognized, and under-treated throughout the world1
Here’s a brief overview of headache disorders. The are among the most common disorders of the nervous system. Their prevalence among adults who are symptomatic at least once within the last year is almost 47% worldwide. Headache disorders are associated with personal and societal burdens of pain, disability, reduced quality of life, and financial burden. However, globally, only a minority of people with headache disorders are appropriately diagnosed by a health care provider. Thus, headache has been underestimated, under-recognized, and under-treated throughout the world.
1. WHO Headache disorders. Available at:

4. Structures Related to Headache
This schematic gives an overview of the structures related to headache. These include blood vessels, muscles in the neck and head, joints, cranial nerves, teeth, sinuses, and the muscles around the eyes. Please take a moment to review this schematic.

5. What Is Migraine?
Neurologically based, common clinical syndrome characterized by recurrent episodic attacks of head pain which serve no protective purpose
The headache is accompanied by associated symptoms
Nausea
Sensitivity to light
Sensitivity to sound
Sensitivity to head movement
The vulnerability to migraine is an inherited tendency in many people
Moving on, we can define migraine as a neurologically based, common clinical syndrome characterized by recurrent episodic attacks of head pain which serve no protective purpose. In migraine the headache is accompanied by associated symptoms, including nausea, sensitivity to light, and sensitivity to sound, sensitivity to head movement. The vulnerability to migraine is an inherited tendency in many people
Lance JW, Goadsby PJ. Mechanism and Management of Headache. London, England: Butterworth-Heinemann; 1998;; Silberstein SD, Lipton RB, Goadsby PJ. Headache in Clinical Practice. 2nd ed. London, England: Martin Dunitz; 2002 Olesen J, Tfelt-Hansen P, Welch KMA. The Headaches. 2nd ed. Philadelphia, PA: Lippincott Williams & Wilkins; 2000.

6. Classification of Migraine
Migraine without aura
Recurrent attacks, lasting minutes, of unilaterally fully reversible visual, sensory, or other CNS symptoms that usually develop gradually and are usually followed by headache and associated migraine symptoms
Migraine with typical aura
Aura consists of visual and/or sensory and/or speech/language symptoms but no motor weakness
Gradual development
Duration of each symptom ≤1 hour
Mix of positive and negative features
Complete reversibility
Chronic Migraine
Headache occurring on ≥15 days/month for >3 months
Headache has the features of migraine headache on ≥8 days/month
Three basic types of migraine exist. First, the migraine without aura is characterized by recurrent attacks, lasting minutes, of unilaterally fully reversible visual, sensory, or other CNS symptoms that usually develop gradually and are usually followed by headache and associated migraine symptoms. Second, the migraine with typical aura is characterized by an aura consists of visual and/or sensory and/or speech/language symptoms but no motor weakness. This aura develops gradually, with a symptom duration of more than an hour, and is characterized by a mix of positive and negative features. Migraine with the typical aura is completely reversible. Finally, chronic Migraine is defined as headache occurring on 15 days or more per month for more than 3 months. Headache with the features of migraine headache occurs on 8 days or more per month.
International Headache Society. 2013

7. Primary vs. Secondary Headache
Primary Headache
Not a symptom of or caused by another disease or condition
Secondary Headache
A symptom of or caused by an underlying disease or condition, such as tumor or infection
Headache can also be classified as primary headache, which is not a symptom of or caused by another disease or condition, or secondary headache, which is a symptom of or caused by an underlying disease or condition, such as tumor or infection.
Mayo Clinic. Headache causes – symptoms. Available at: Accessed 15 January 2015.

8. Prevalence of Headache Disorders by Headache Type
Lifetime Prevalence
Primary Headache Disorders
Tension-type
Migraine
78%
16%
Secondary Headache Disorders
Fasting
Sinus/nasal disorder
Head injury
Non-vascular intracranial disorder*
19%
15% 4%
0.5%
This table gives a breakdown of the prevalence of primary and secondary headache disorders.
*Including brain tumor
Rasmussen BK et al. J Clin Epidemiol. 1991;44(11):

9. Age- and Gender-Specific Prevalence of Migraine
In males and females, the prevalence distribution of migraine is an inverted U-shaped curve. Prevalence rises through early adult life and then falls after midlife in both genders. At all postpubertal ages, migraine is substantially more common in women than in men.
Lipton RB et al. Headache. 2001;41(7):

10. Prevalence of Migraine in Three Population-based Studies
The annual incidence of migraine among women is about 18%, which is triple the incidence among men. Migraine is the headache that drives patients to seek medical help, and most of these patients are women.
Stewart WF et al. JAMA. 1992;267(1):64-9; Lipton RB et al. Headache. 2001;41(7):646-57; Lipton RB et al. Neurology Jan 30;68(5):343-9.

11. Prevalence of Migraine by Ethnicity
Estimates of migraine prevalence from African American and Asian American populations are lower than those observed in Caucasian American populations. These differences in prevalence are more likely caused by race-related differences in genetic vulnerability to migraine than to cultural differences.
Stewart WF et al. Neurology. 1996;47(1):52-9.

12. Prevalence of Headache Disorders by Geographic Area
The prevalence in headache is greater in Europe and the Americas than in Africa and Asia. In all parts of the world headaches are more prevalent in women than in men.
Lipton RB et al. J Headache Pain. 2003;4[Suppl 1]:S3-S11.

13. Specific Types of Secondary Headaches
Type of Headache
Cause
External compression
Pressure-causing head gear
Rebound
Overuse of pain medication
Sinus
Inflammation and congestion in sinus cavities
Spinal
Low levels of cerebrospinal fluid (e.g., due to trauma, spinal tap, spinal anesthesia)
Thunderclap
Subarachnoid haemorrhage is the most common cause
This slide lists the most common causes of secondary headaches and their causes.
An ice cream headache – or brain freeze – is a secondary headache
Mayo Clinic. Headache causes – symptoms. Available at: Accessed 15 January 2015; Ducros A, Bousser MG. BMJ ;346:e8557.

14. Prevalence of Headache Disorders
Top Five Reasons for Emergency Department Visits*
Headache is the fifth leading cause of emergency department visits in the United States, estimated to account for over 4 million visits each year. Among women, it rises to third place, accounting for 2.6% of emergency department visits in that group.
*National Hospital Ambulatory Medical Care Survey, 2009
Smitherman TA et al. Headache. 2013;53(3):

15. Depression, Anxiety, and Migraine
This slide illustrates the prevalence and severity of anxiety and depression among people with migraine. Anxiety and depression are common among people with migraine and remain largely unrecognized.
HAD = J Devlen. J R Soc Med. 1994;87(6):

16. Prevalence of Psychiatric Disorders in Three Pain Conditions
No Migraine
Migraine
Odds Ratio (CI)
Depression
12.3%
28.5%
2.84 (2.19, 3.70)
Panic attacks
5.5%
17.4%
3.58 (2.59, 4.97)
GAD
2.5%
9.1%
3.86 (2.48, 6.00)
No Arthritis
Arthritis
Odds Ratio
13.1%
18.2%
1.48 (1.16, 1.88)
5.8%
11.2%
2.09 (1.54, 2.83)
2.7%
5.6%
2.17 (1.42, 3.33)
No Back Pain
Back Pain
12.4%
21.0%
1.87 (1.49, 2.36)
5.3%
13.0%
2.69 (2.00, 3.62)
6.2%
2.54 (1.67, 3.85)
This slide illustrated the prevalence of depression and anxiety disorders associated with migraine, arthritis, and back pain. Note that Migraine is more strongly associated with both depression and anxiety disorders than arthritis or back pain.
All findings significant at p<0.001
CI = confidence interval; GAD = generalized anxiety disorder
McWilliams LA et al. Pain. 2004;111(1-2):77-83.

17. Migraine and Depression: A Bidirectional Relationship with Common Neurobiology
Monoamine and peptide transmitters may be involved in depression
Endorphins and encephalins are involved in mood and pain control
Serotonin has been implicated in migraine, and tension-type headache
Also implicated in mood disorders, anxiety disorders, sleep disorders, eating disorders, and obsessive-compulsive behavior
Evidence suggests dopamine is involved in migraine
Migraine prodrome often characterised by dopaminergic symptoms
Anti-dopaminergic drugs can often be helpful in treating migraine
Migraine and depression share a bidirectional relationship with common neurobiology. Specifically, monoamine and peptide transmitters may be involved in depression, and endorphins and encephalins are involved in mood and pain control. Serotonin has been implicated in migraine, and tension-type headache, and it is also implicated in mood, anxiety, sleep, eating and disorders, as well as in obsessive-compulsive behavior. Dopamine may also be involved in the pathophysiology. Specifically, the migraine prodrome often characterised by dopaminergic symptoms, and anti-dopaminergic drugs can often be helpful in treating migraine. Thus, severe headache, severe somatic symptoms, and major depression may be linked through dysfunction of the serotonergic and dopaminergic systems.
Severe headache, severe somatic symptoms, and major depression may be linked through dysfunction of the serotonergic and dopaminergic systems
Frediani F, Villani V. Migraine and depression. Neurol Sci. 2007;28 Suppl 2:S161-5.

18. Literature Cited
Devlen, J. (1994). Anxiety and depression in migraine. Journal of the Royal Society of Medicine, 87(6), 338–341. Frediani, F., & Villani, V. (2007). Migraine and depression. Neurological Sciences: Official Journal of the Italian Neurological Society and of the Italian Society of Clinical Neurophysiology, 28 Suppl 2, S161– Goadsby, P. J., Lipton, R. B., & Ferrari, M. D. (2002). Migraine—current understanding and treatment. N Engl J Med, 346(4), 257–270. Headache Causes - Mayo Clinic. (n.d.). Retrieved June 18, 2015, from (IHS, H. C. C. of the I. H. S. (2013). The international classification of headache disorders, (beta version). Cephalalgia, 33(9), 629–808. Lipton, R. B., Bigal, M. E., Diamond, M., Freitag, F., Reed, M. L., Stewart, W. F., & AMPP Advisory Group. (2007). Migraine prevalence, disease burden, and the need for preventive therapy. Neurology, 68(5), 343– Lipton, R. B., Stewart, W. F., Diamond, S., Diamond, M. L., & Reed, M. (2001). Prevalence and burden of migraine in the United States: data from the American Migraine Study II. Headache, 41(7), 646–657.

19. Literature Cited (Continued)
McWilliams, L. A., Goodwin, R. D., & Cox, B. J. (2004). Depression and anxiety associated with three pain conditions: results from a nationally representative sample. Pain, 111(1-2), 77–83. Olesen, B., Tfelt-Hansen, P., & Welch, K. (2000). The Headaches (2nd ed.). Philadelphia pA: Lippincott, Williams & Wilkins. Rasmussen, B. K., Jensen, R., Schroll, M., & Olesen, J. (1991). Epidemiology of headache in a general population--a prevalence study. Journal of Clinical Epidemiology, 44(11), 1147–1157. Silberstein, S., Lipton, R., & Goadsby PJ. (2002). Headache in Clinical Practice. (2 nd ed.). London: Martin Dunitz. Smitherman, T. A., Burch, R., Sheikh, H., & Loder, E. (2013). The prevalence, impact, and treatment of migraine and severe headaches in the United States: a review of statistics from national surveillance studies. Headache, 53(3), 427– Stewart, W. F., Lipton, R. B., Celentano, D. D., & Reed, M. L. (1992). Prevalence of migraine headache in the United States. Relation to age, income, race, and other sociodemographic factors. JAMA, 267(1), 64–69. Stewart, W. F., Lipton, R. B., & Liberman, J. (1996). Variation in migraine prevalence by race. Neurology, 47(1), 52–59.

20. Literature Cited (Continued 2)
WHO | Headache disorders. (n.d.). Retrieved June 18, 2015, from