Tension headache overview

# Overview
A common primary headache disorder, characterized by a dull, non-pulsatile, diffuse, band-like (or vice-like) pain of mild to moderate intensity in the head, scalp or neck. The subtypes are classified by frequency and severity of symptoms. There is no clear cause even though it has been associated with muscle contraction and stress. Tension headaches, which were renamed tension-type headaches by the International Headache Society in 1988, are the most common type of primary headaches. The pathophysiology for tension type headache is multifactorial and generally includes increased sensitivity of central and peripheral nociceptive  pathways, environmental and genetic factors. It includes hypersensitivity of central and peripheral nociceptive  pathways: lack of habituation, Nitric oxide and combination of genetic and envirommental factors. The exact cause of tension-type headaches is still unknown. Multiple pathophysiologic mechanisms explain the possible etiologies or causative factors.  Differential diagnosis if tension type headache includes; Migraine, Cluster headache, Secondary headaches such as Medication overuse, Sinus headache and Cervicogenic headache.  Tension headache is one of the most common type of headaches. Tension-type headache (TTH) is the most prevalent headache in the general population. Tension-type headache (TTH) is the second-most prevalent disorder in the world. A Danish Registry showed 1 year prevalances of  infrequent episodic, frequent episodic and and chronic TTH were 63.5, 21.6 and 0.9% respectively.  Various precipitating factors may cause TTH in susceptible individuals. One half of patients with TTH identify stress or hunger as a precipitating factor; stress, sleep deprivation, irregular meal time (hunger), eyestrain. Diagnostic criteria for tension-type headache is specified by the International Classification of Headache Disorders, 3rd edition (ICHD-3).  Tension-type headache pain is often described as a constant pressure, as if the head were being squeezed in a vise. The pain is frequently bilateral which means it is present on both sides of the head at once. Tension-type headache pain is typically mild to moderate, but may be severe. In contrast to migraine, the pain does not increase during exercise. Tension type headache may have following examination findings: Increased pericranial muscle (head, neck or shoulders) and myofascial tissue tenderness on manual palpation. Increased number of myofacial trigger points: frontal, temporal, masseter, ptrygoid, sternocleidomastoid, splenius, and trapezius mucles. Neuro-imaging is generally  not indicated for patients with TTH. Usually indicated if abnormal neurologic examination findings or atypical presentation or presentation not fulfilling the ICHD-3 criteria. Neuro-imaging with an magnetic resonance imaging (MRI) scan with and without contrast is preferred to non-contrast computed tomography (CT) scan. MRI is usually indicated to rule out underlying structural brain lesion or to evaluate brain and pituitary gland in patient presenting with typical features or highly suspicious of TTH. Episodic tension-type headaches generally respond well to over-the-counter analgesics, such as paracetamol, ibuprofen or aspirin.  Simple analgesic monotherapy such as NSAIDS or aspirin are recommended (Grade 1A) for episodic TTH treatment requiring patients. Simple analgesic monotherapy is used in combination with caffeine for TTH patients who are unresponsive or have a poor response to analgesic monotherapy (Grdae 2A). Combination therapies including opioids or butalbital are not recommended as first line agents for TTH Rx (Grade 1C). Inpatient treatment for severe TTH can be treated in addition to the above mentioned treatment with chlorpromazine, metoclopramide, combination of metoclopramide and diphenhydramine and intramuscular ketorolac.  TTH prevention and prophylactic treatment is generally indicated for chronic TTH and frequent episodic TTH. Data regarding pharmacologic prevention and prophylactic treatment is limited and not well established. Drugs that can be used are; TCA (amitriptyline), SSRI (mirtazapine, venlafaxine), and anticonvulsants (gabapentin, topiramate). Behavioral treatments include; relaxation, biofeedback, and CBT. For patients with frequent episodic or chronic TTH, combined Rx with TCA plus stress management therapy is recommended rather than alone therapy with TCA or behavioral therapy alone. (Grade 2B). For patients with frequent episodic or chronic TTH, having preference for pharmacologic therapy rather than behavioral therapy, TCA with amitriptyline is recommended. (Grade 2B). For patients with frequent episodic or chronic TTH, not needing pharmacologic therapy, electromyography biofeedback combined with relaxation therapy is recommended. (Grade 2B). For patients with frequent episodic or chronic TTH, who cannot tolerate or require more effective treatments such as amitriptyline and biofeedback, accupuncture (Grade 2B) or physical therapy (Grade 2C) is recommended.

# Historical Perspective
Tension headaches, which were renamed tension-type headaches by the International Headache Society in 1988, are the most common type of primary headaches. In the earlier days, it was known as stress or tension headache, muscle-contraction headache, psychomyogenic headache,  and psychogenic headache.

# Classification
Tension-type headaches can be episodic or chronic. Episodic tension-type headaches are defined as tension-type headaches occurring less than 15 days a month, whereas chronic tension headaches occur 15 days or more a month for at least 6 months. Tension-type headaches can last from minutes to days or even months, though a typical tension headache lasts 4-6 hours.

# Pathophysiology
The pathophysiology for tension type headache is multifactorial and generally includes increased sensitivity of central and peripheral nociceptive  pathways, environmental and genetic factors. It includes hypersensitivity of central and peripheral nociceptive  pathways: lack of habituation, Nitric oxide and combination of genetic and envirommental factors.

# Causes
The exact cause of tension-type headaches is still unknown. Multiple pathophysiologic mechanisms explain the possible etiologies or causative factors.

# Differential Diagnosis
Differential diagnosis if tension type headache includes; Migraine, Cluster headache, Secondary headaches such as Medication overuse, Sinus headache and Cervicogenic headache.

# Epidemiology and Demographics
Tension headache is one of the most common type of headaches. Tension-type headache (TTH) is the most prevalent headache in the general population. Tension-type headache (TTH) is the second-most prevalent disorder in the world. A Danish Registry showed 1 year prevalances of  infrequent episodic, frequent episodic and and chronic TTH were 63.5, 21.6 and 0.9% respectively. A United States study showed that the 1 year prevalences of episodic and chronic TTH were 38.3 and 2.2%. Females have a higher prevalence compared to males. Limited data suggests TTH to be more prevalent in whites compared to black in the US, irrespective of sex. A recent study showed that TTH prevalence peaking in the 4th decade. A Danish study showed decreasing prevalence of TTH with increasing age.

# Risk Factors
Various precipitating factors may cause TTH in susceptible individuals. One half of patients with TTH identify stress or hunger as a precipitating factor; stress, sleep deprivation, irregular meal time (hunger), eyestrain. Other triggers of tension headaches include: alcohol , caffeine, colds, the flu, or a sinus infection, dental problems such as jaw clenching or teeth grinding, excessive smoking and fatigue or overexertion.

# Natural History, Complications and Prognosis
Tension headache is considered to have a high socioeconomic impact, being the most common type of headache. It is a life long condition and usually results in reduced quality of life and marked functional disability.  Tension type headache if left untreated or undiagnosed, is found to be associated with increased risk of depression and suicide, due to its huge socioeconomic impact. Tension headaches that occur as a symptom of another condition are usually relieved when the underlying condition is treated. Frequent use of pain medications in patients with tension-type headache may lead to the development of medication overuse headache.

# Diagnosis

## Diagnostic criteria
Diagnostic criteria for tension-type headache is specified by the International Classification of Headache Disorders, 3rd edition (ICHD-3).

## History and Symptoms
Tension-type headache pain is often described as a constant pressure, as if the head were being squeezed in a vise. The pain is frequently bilateral which means it is present on both sides of the head at once. Tension-type headache pain is typically mild to moderate, but may be severe. In contrast to migraine, the pain does not increase during exercise.

## Physical Examination
Tension type headache may have following examination findings: Increased pericranial muscle (head, neck or shoulders) and myofascial tissue tenderness on manual palpation. Increased number of myofacial trigger points: frontal, temporal, masseter, ptrygoid, sternocleidomastoid, splenius, and trapezius mucles.

## Laboratory Findings
Laboratory investigations, such as electrophysiologic testing (eg, evoked potential, electroencephalography) and examination of the cerebrospinal fluid, are not found to be helpful and needs more studies for further evaluation.

## CT
Neuro-imaging is generally  not indicated for patients with TTH. Usually indicated if abnormal neurologic examination findings or atypical presentation or presentation not fulfilling the ICHD-3 criteria. Neuro-imaging with a non-contrast computed tomography (CT) scan is usually indicated to rule out underlying structural brain lesion or to evaluate brain and pituitary gland in patient presenting with typical features or highly suspicious of tension-type headache.

## MRI
Neuro-imaging is generally not indicated for patients with TTH. Usually indicated when abnormal neurologic examination findings or atypical presentation or presentation not fulfilling the ICHD-3 criteria. Neuro-imaging with an magnetic resonance imaging (MRI) scan with and without contrast is preferred to non-contrast computed tomography (CT) scan. MRI is usually indicated to rule out underlying structural brain lesion or to evaluate brain and pituitary gland in patient presenting with typical features or highly suspicious of TTH.

# Treatment

## Medical Therapy
Episodic tension-type headaches generally respond well to over-the-counter analgesics, such as paracetamol, ibuprofen or aspirin.  Simple analgesic monotherapy such as NSAIDS or aspirin are recommended (Grade 1A) for episodic TTH treatment requiring patients. Simple analgesic monotherapy is used in combination with caffeine for TTH patients who are unresponsive or have a poor response to analgesic monotherapy (Grdae 2A). Combination therapies including opioids or butalbital are not recommended as first line agents for TTH Rx (Grade 1C). Inpatient treatment for severe TTH can be treated in addition to the above mentioned treatment with chlorpromazine, metoclopramide, combination of metoclopramide and diphenhydramine and intramuscular ketorolac.

## Prevention
TTH prevention and prophylactic treatment is generally indicated for chronic TTH and frequent episodic TTH. Data regarding pharmacologic prevention and prophylactic treatment is limited and not well established. Drugs that can be used are; TCA (amitriptyline), SSRI (mirtazapine, venlafaxine), and anticonvulsants (gabapentin, topiramate). Behavioral treatments include; relaxation, biofeedback, and CBT. For patients with frequent episodic or chronic TTH, combined Rx with TCA plus stress management therapy is recommended rather than alone therapy with TCA or behavioral therapy alone. (Grade 2B). For patients with frequent episodic or chronic TTH, having preference for pharmacologic therapy rather than behavioral therapy, TCA with amitriptyline is recommended. (Grade 2B). For patients with frequent episodic or chronic TTH, not needing pharmacologic therapy, electromyography biofeedback combined with relaxation therapy is recommended. (Grade 2B). For patients with frequent episodic or chronic TTH, who cannot tolerate or require more effective treatments such as amitriptyline and biofeedback, accupuncture (Grade 2B) or physical therapy (Grade 2C) is recommended.