Definition and Overview
Tension-type headache (TTH) is the most common type of primary headache as defined by the International Classification of Headache Disorders (ICHD-3) [2]. The headache is characterized by a pressing or tightening quality without pulsation and is typically bilateral. Even if photophobia or phonophobia is present, only one is permitted, and nausea or vomiting does not occur.
Globally, the one-year prevalence of tension-type headache is reported at approximately 38.3%, with a lifetime prevalence exceeding 78% [1]. Women (approximately 86%) show a higher lifetime prevalence than men (approximately 63%) [3].
Diagnostic Criteria (ICHD-3)
Episodic tension-type headache (episodic TTH) [2]:
1. Duration: 30 minutes to 7 days
2. At least 2 of the following 4 characteristics:
- Bilateral location
- Pressing or tightening (non-pulsating) quality
- Mild to moderate intensity
- Not aggravated by routine physical activity (walking, climbing stairs)
3. Both of the following:
- No nausea or vomiting
- No more than one of photophobia or phonophobia (not both)
Subtypes based on frequency:
- Infrequent episodic: Less than once per month (fewer than 12 days per year)
- Frequent episodic: 1-14 days per month
- Chronic: 15 or more days per month for more than 3 months
Causes and Mechanisms
The pathophysiology of tension-type headache involves a combination of peripheral and central mechanisms [3].
Peripheral Mechanisms (Episodic TTH)
Sustained tension in the scalp, neck, and shoulder muscles and fascia leads to the formation of myofascial trigger points. Pain signals from these trigger points are transmitted to the trigeminal system via A-delta and C fibers [3]. Poor posture, prolonged static positioning (computer work), and excessive tension in the pericervical muscles are direct contributing factors.
Central Mechanisms (Chronic TTH)
In chronic tension-type headache, central sensitization of pain processing pathways is the predominant mechanism [3]. Dysfunction of the pain inhibitory system causes stimuli that would not normally be perceived as painful to be interpreted as pain. Even when pericranial muscle contraction increases, the centrally sensitized state processes these signals as intensified pain.
Triggering Factors
- Psychological: Mental stress, anxiety, depression, tension
- Physical: Sleep deprivation or oversleeping, poor posture, prolonged static positioning, physical fatigue
- Environmental: Caffeine intake or withdrawal, dehydration, bright light, noise, strong odors, weather changes
Symptoms
Pain Characteristics
The pain of tension-type headache is typically described as follows.
- Bilateral: A sensation of pressure encompassing the forehead, temples, and occiput.
- Pressing or tightening: Feels like a band or helmet compressing the head, or as if a heavy weight is resting on it.
- Non-pulsating: Does not throb in rhythm with the heartbeat.
- Mild to moderate: Not severe enough to completely impair daily activities.
Associated Symptoms
- Stiffness and tenderness of the scalp, neck, and shoulder muscles
- Decreased concentration
- Photophobia or phonophobia (only one may be present)
- Decreased appetite
Treatment
Acute Treatment
For acute episodes of episodic tension-type headache, nonsteroidal anti-inflammatory drugs (ibuprofen, naproxen, aspirin) or paracetamol (acetaminophen) are first-line medications [4]. While caffeine enhances analgesic efficacy, caution is warranted due to the risks of caffeine overuse and withdrawal headache.
Non-Pharmacological Acute Treatment
- Relaxation training and deep breathing exercises
- Cervical and scalp massage
- Neck and shoulder stretching
- Warm compresses (for muscle tension relief)
- Adequate fluid intake
Preventive Treatment
Preventive treatment is recommended for chronic tension-type headache (15 or more days per month) [4].
Pharmacological prevention:
- Amitriptyline (tricyclic antidepressant) at 10-75 mg/day is the first-line preventive agent with the strongest evidence [4].
- Mirtazapine and venlafaxine have also shown reported efficacy.
Non-pharmacological prevention:
- Relaxation training and biofeedback: EMG biofeedback is effective in reducing headache frequency and intensity [4].
- Cognitive behavioral therapy: Trains stress management and pain coping strategies.
- Physical therapy: Treatment of cervical dysfunction and myofascial trigger points.
- Transcranial magnetic stimulation (TMS): Being investigated as an adjunctive therapy to stimulate central pain inhibitory circuits in chronic tension-type headache.
Medication Overuse Headache Management
Medication overuse headache may develop when analgesics are taken 10-15 or more days per month. In such cases, discontinuation of the overused medication is essential despite short-term withdrawal symptoms, and should be conducted under specialist supervision [4].
Clinical Course and Prognosis
Follow-up studies indicate that approximately 45% of tension-type headache patients experience headache resolution or reduction to low frequency after 10 years, while approximately 39% continue to have persistent headaches [5]. Known risk factors for chronification include excessive headache medication use, sleep disorders, and comorbid anxiety or depression [5].
Lifestyle Management
- Headache diary: Record the date, duration, intensity, triggering factors, and medications taken for each headache episode to identify triggers.
- Regular sleep schedule: Go to bed and wake up at the same time every day. Changes in weekend sleep patterns can also trigger headaches.
- Regular meals: Do not skip meals. Hypoglycemia is a common headache trigger.
- Fluid intake: Drink 1.5-2 liters of water per day. Dehydration worsens headaches.
- Posture correction: Adjust monitor height and chair positioning during computer work, and stretch every hour.
- Exercise: Aerobic exercise 3-5 times per week helps reduce headache frequency.