Most people have experienced a tension-type headache at some point in their life. Tension-type headache is the most frequent type of headache, but in most of the affected subjects it occurs only occasionally. Tension-type headache is usually bilateral, dull and pressing. Pain intensity is low to moderate, annoying but not leading to severe impairment in daily life. Accompanying symptoms such as nausea and light and noise intolerance, which are typical of migraine, are usually not present in tension-type headache. Many patients describe tension-type headache as feeling like the head is being squeezed in a vice, or like a tight band around the head. Some patients also have a feeling of drowsiness. Tension-type headache usually does not get worse with physical exercise; on the contrary, it may improve with outdoor activity. The duration of a tension-type headache attack may vary greatly, ranging from half an hour to several days.
What is the course of tension-type headache?
Tension-type headache may be episodic or chronic. In the chronic form, headaches are present on 15 days or more per month for at least three months. In the episodic form, the number of headache days is less than 15 per month. In chronic tension-type headache, slight nausea or increased sensitivity to light or sounds may occur. Vomiting or worsening by physical activity are typical migraine symptoms, which are not present in tension-type headache. Episodic tension-type headache is very frequent. Normally, it does not cause significant impairment in daily life and is well controlled by standard painkillers. In contrast, chronic tension-type headache is rare and, in most cases, develops from the episodic form. An important risk factor for the development of chronic tension-type headache is regular intake of painkillers. It is therefore important to rule out medication overuse before making the diagnosis and starting the treatment (see below).
Moreover, genetic factors may play a role in the development of chronic tension-type headache. The risk of developing chronic tension-type headache is three times higher in families with other affected members. Epidemiologic studies have shown that persons with chronic tension-type headache suffer from comorbid depression, anxiety or panic attacks more often than persons without headache. It is not clear if there is a causal relationship here. On the one hand, depression increases the risk of suffering from headache. On the other hand, frequent headaches and concomitant reduction of quality of life also lead to an increased risk of depression.
Simultaneous occurrence of migraine and tension-type headache is a frequent diagnostic problem. In these cases it is often not clear if the less severe, bilateral, dull or pressing headache indeed corresponds to a tension-type headache or instead to a less severe migraine attack. There are several arguments in favour of this view. First, the presumed tension-type headache may evolve into a full migraine attack within hours. Second, application of migraine-specific drugs (triptans) is often successful in these headaches but not in true tension-type headache.
What is the cause of tension-type headache?
Although tension-type headache is a frequent affliction, its origin is not clear. Possibly, there are several different factors that lead to a common type of headache described as tension-type headache. The most common hypothesis is that increased tension of the neck muscles leads to increased sensitisation of pain-processing centres in the brain if continuously present. No alteration of the muscles themselves has been found.
When alteration of the central pain processing structures has set in, tension-type headache is more difficult to treat. The ongoing muscle tension further reinforces these mechanisms, resulting in a vicious circle. However, these mechanisms are not dangerous and physical damage is not encountered.
How is the diagnosis of tension-type headache made?
If possible, the diagnosis of tension-type headache should be made by a headache specialist. The diagnosis is supported by the typical history and a normal physical examination that does not give reason to suspect other causes of headache. There is no further examination that might corroborate the diagnosis of tension-type headache. Additional examinations such as a computed tomography or magnetic resonance imaging are necessary only if it is suspected that there is another disorder underlying the headache.
How is tension-type headache treated?
Treatment of the acute headache attack has to be differentiated from preventive treatment. Most common painkillers, such as acetylsalicylic acid 500 mg, paracetamol 500 mg or ibuprofen 400 mg are effective in tension-type headache. Alternatively, essential oils such as peppermint oil can be used. The oil should be spread generously on the forehead, temples and neck. A major problem is that frequent intake of painkillers on more than 10 days per month can lead to an exacerbation of headache; thus it is recommended that painkillers are used restrictively, especially in chronic tension-type headache. Therefore, it is important to keep track of the number of medication days per month.
Preventive treatment first includes general measures such as ensuring that the day is structured, with breaks and sufficient sleep and the reduction of stress factors. Moreover, regular exercise, e.g. cycling, swimming, running or Nordic walking, if possible three times per week for at least 30 min is recommended as well as relaxation techniques such as progressive muscle relaxation (PMR) that is effective in both migraine and tension-type headache.
When there is a continuous increase of headache days, with the risk of a previously episodic headache becoming chronic, preventive medication should be started in addition to the general measures described above. Preventive drugs are not direct painkillers. In contrast, they are supposed to act on pain processing in the brain and thereby lead to a reduction of tension-type headache. The exact mechanism of action is not known. Preventive medication has to be taken regularly, i.e. daily. Its action sets in only after about 4-6 weeks. In tension-type headache, mainly antidepressant drugs are used that act not only on headache but also on other types of pain. For preventive treatment of headache, lower doses are used compared to the treatment of depression. The first choice is amitriptyline, alternatively other types of antidepressants such as mirtazapine or venlafaxine can be used. Tizanidine and valproate are used as drugs of second choice, they are not antidepressant drugs. Botulinum toxin is not effective in chronic tension-type headache.
All of these drugs are prescription drugs and blood tests or ECG controls are required during the initial dosing phase. If the dose is increased slowly, these drugs are usually well tolerated. If there is a significant reduction of headache days and severity, the preventive drug is maintained for at least 6-9 months.
There are also non-pharmacological methods of tension-type headache treatment, including the general measures described above (regular structure of the day, stress reduction and stress coping, physical exercise and relaxation techniques). Most of the time, a combination of pharmacological and non-pharmacological methods is more effective than only using a pharmacological method. Acupuncture can be tried; however, results vary between studies and are less pronounced than with the methods described above.