Tension-Type Headache (TTH): Clinical Guidelines

List of Abbreviations

AGB – medication-overuse headache

BF – Biofeedback

VAS – visual analogue scale

GB – headache

GBN – tension-type headache

DPM – pericranial muscle dysfunction

KN – comorbid disorders

CBT – cognitive behavioral therapy

LIGB – medication-induced (overuse) headache

LFK - therapeutic exercise

ICD-10 – International Classification of Diseases, 10th Revision

ICHD-3 – International Classification of Headache Disorders, 3rd edition

MRI — magnetic resonance imaging

MTS – muscle-tonic syndrome

MFS – myofascial syndrome

NPVP – nonsteroidal anti-inflammatory drugs (ATC non-steroidal

anti-inflammatory and antirheumatic products)

RCTs – Randomized Controlled Trials

SSRIs – Selective Serotonin Reuptake Inhibitors

UZDG - Doppler ultrasound

HGBN – chronic tension-type headache

HM – chronic migraine

EGBN – episodic tension-type headache

Terms and Definitions

Abuse headache (AH) — see medication-overuse headache.

Causative drugs (abused drugs) – drugs that, when taken in excess, can lead to the development of medication-overuse headache (all classes of analgesics).

Secondary headaches (HA) - HAs that are a symptom of another disorder (symptomatic) HAs occurring de novo in close temporal relation to another (causative) disorder known from scientific data to be a cause of HA.

Tension-type headache (TTH) - one of the most common forms of primary HA, manifesting as pain episodes lasting from 30 minutes to several days.

Pericranial muscle dysfunction (PMD) - painful tension of the muscles of the head, face, and neck.

Inhibitory antinociceptive mechanisms - the descending pain-modulating or antinociceptive control system.

Comorbid disorders (CD) - one or more pathological conditions observed in the same patient, pathogenetically linked to each other or coinciding in the time of onset regardless of the activity of each of them.

Medication-overuse headache (MOH) – a clinical variety of secondary chronic HA developing in patients with primary HAs (migraine and TTH) due to the excessive use of acute HA medications.

Medication overuse (MO) - excessive use of analgesic medications for acute relief of HA.

Primary headaches - idiopathic (benign) HAs that are not associated with organic pathology of the brain, cerebral vessels, any structures of the head and neck, or systemic diseases.

Peripheral sensitization – an increased response of excited nociceptive neurons of the peripheral nervous system to normal and/or subthreshold stimulation.

Headache triggers - endogenous and exogenous factors capable of precipitating a HA attack/episode.

Factors of headache chronification - genetic, metabolic, environmental, behavioral, and/or psychological factors that contribute to the increased frequency of existing HA.

Chronification of headache - a gradual increase in the number of HA days per month.

Chronic headaches - HAs occurring on 15 or more days per month for >3 months.

Central sensitization (CS) - amplification of neural signaling within the central nervous system that results in generalized hypersensitivity to pain. CS reflects heightened activity of pain-processing systems, reduced activity of descending pain-inhibitory pathways, and consequently a disruption of endogenous pain control.

Cephalalgia – headache (synonym).

1. Brief information on the disease or condition

1.1 Definition of the disease or condition

Tension-type headache (TTH) is one of the most common forms of primary headache (HA), presenting as a bilateral pressing or tightening HA of mild to moderate intensity, lasting from 30 minutes to several days. The HA is not aggravated by routine physical activity and is not accompanied by nausea, though decreased appetite, photophobia, or phonophobia may occur [1].

1.2 Etiology and pathogenesis of the disease or condition (group of diseases or conditions)

Both peripheral and central nociceptive (pain) mechanisms are involved in the pathogenesis of TTH [2, 3]. Peripheral mechanisms are related to painful tension of the head and neck muscles, muscle hypoxia, and the release of pro-inflammatory pain mediators into the bloodstream. As a result, the excitability of nociceptive neurons in the dorsal horns of the spinal cord increases [3, 4]. The main central mechanism of TTH involves a decrease in the activity of the inhibitory antinociceptive system of the brainstem, which facilitates the transmission of pain impulses and leads to the development of central sensitization (CS), which in turn contributes to the chronification of TTH [3]. In episodic TTH (ETTH), peripheral pathological factors play a substantial role, whereas in chronic TTH (CTTH), central factors associated with the development of CS predominate. Affective disorders (depression and anxiety) contribute to the chronification of the existing pain syndrome [2, 3, 5].

1.3 Epidemiology of the Disease or Condition

Both peripheral and central nociceptive (pain) mechanisms are involved in the pathogenesis of TTH [2, 3]. Peripheral mechanisms are related to painful tension of the head and neck muscles, muscle hypoxia, and the release of pro-inflammatory pain mediators into the bloodstream. As a result, the excitability of nociceptive neurons in the dorsal horns of the spinal cord increases [3, 4]. The main central mechanism of TTH involves a decrease in the activity of the inhibitory antinociceptive system of the brainstem, which facilitates the transmission of pain impulses and leads to the development of central sensitization (CS), which in turn contributes to the chronification of TTH [3]. In episodic TTH (ETTH), peripheral pathological factors play a substantial role, whereas in chronic TTH (CTTH), central factors associated with the development of CS predominate. Affective disorders (depression and anxiety) contribute to the chronification of the existing pain syndrome [2, 3, 5].

1.4 Features of Coding the Disease or Condition

G44 Other headache syndromes

G44.2 Tension-type headache

G44.3 Chronic post-traumatic headache

G44.4 Drug-induced headache, not elsewhere classified

G44.8 Other specified headache syndrome

G90.8 Other disorders of the autonomic [vegetative] nervous system

1.5 Classification of the disease or condition

According to the latest version of the International Classification of Headache Disorders (ICHD-3, 2018), TTH is classified among primary (benign) cephalalgias (Part I of ICHD-3), which are not associated with organic lesions of the brain, cerebral vessels, or other structures located in the head and neck region, nor with systemic diseases (Table 1) [1].

Table 1. Table of Contents of the International Classification of Headache Disorders, 3rd Edition (2018) [1]

According to ICHD-3, two main forms of tension-type headache (TTH) are distinguished: episodic TTH (ETTH), occurring on no more than 15 days per month (or 180 days per year), and chronic TTH (CTTH), occurring on more than 15 days per month (or more than 180 days per year). ETTH is further subdivided into infrequent and frequent ETTH (patients with the former form generally do not seek medical care).

Depending on the presence or absence of muscle dysfunction, ETTH and CTTH are classified into forms "without pericranial muscle tenderness" and the much more common forms "with pericranial muscle tenderness" [4]. If one of the criteria for TTH is not met, a diagnosis of "Probable tension-type headache" can be made (Table 2) [1].

Table 2. Classification of tension-type headache (according to the International Classification of Headache Disorders, 3rd edition, 2018) [1]

1.6 Clinical presentation of the disease or condition

TTH manifests as recurrent episodes of bilateral, diffuse, pressing, non-pulsating headache, described as a "helmet" or "band" around the head, affecting the frontal, temporal, parietal, and possibly occipital regions or the entire head, with mild to moderate intensity (4–7 points on the Visual Analog Scale (VAS) for pain; see Appendix G2). The headache is not aggravated by routine physical activity; conversely, walking or light physical activity may relieve TTH. Associated symptoms are typically absent, though mild nausea and decreased appetite may occur. Photophobia and phonophobia are rare in TTH and do not occur simultaneously, unlike in migraine [1].

2. Diagnostics, medical indications and contraindications for diagnostic methods

Comment: The ICHD-3, approved by the International Headache Society in 2018, is the primary diagnostic tool for all forms of headache and facial pain. Tables 3a–3i present the diagnostic criteria for episodic and chronic TTH and their subtypes.

Table 3a. Diagnostic criteria for infrequent episodic tension-type headache (ICHD-3, 2018) [1]

Table 3b. Diagnostic criteria for infrequent episodic tension-type headache associated with pericranial tenderness (ICHD-3, 2018) [1]

Table 3c. Diagnostic criteria for infrequent episodic tension-type headache not associated with pericranial tenderness (ICHD-3, 2018) [1]

Table 3d. Diagnostic criteria for frequent episodic tension-type headache (ICHD-3, 2018) [1]

Table 3e. Diagnostic criteria for frequent episodic tension-type headache associated with pericranial tenderness (ICHD-3, 2018) [1]

Table 3f. Diagnostic criteria for frequent episodic tension-type headache not associated with pericranial tenderness (ICHD-3, 2018) [1]

Table 3g. Diagnostic criteria for chronic tension-type headache (ICHD-3, 2018) [1]

Table 3h. Diagnostic criteria for chronic tension-type headache associated with pericranial tenderness (ICHD-3, 2018) [1]

Table 3i. Diagnostic criteria for chronic tension-type headache not associated with pericranial tenderness (ICHD-3, 2018) [1]

Combination of tension-type headache and medication-overuse headache (MOH). Tension-type headache, especially CTTH, can be combined with the overuse of acute pain-relieving medications (medication overuse). Significant overuse may lead to the development of MOH, presented in section 8.2 of the ICHD-3 "Medication-overuse headache" (Tables 4a and 4b) [1]. Medication overuse contributes to an increased frequency of headache episodes up to the development of CTTH and is considered one of the leading factors in the chronification of tension-type headache [2, 8, 10].

Table 4a. General diagnostic criteria for MOH (ICHD-3, 2018) [1]

Table 4b. Classification of MOH forms (according to ICHD-3, 2018) [1]

Comments: diagnosis of MOH is based on clinical evaluation of the headache, analysis of data regarding the number and frequency of pain-relieving medication intake, and the type of overused drugs [1]. To clarify these characteristics, it is advisable for patients to keep a headache diary (Appendix A3.1).

MOH manifests as a diffuse, monotonous headache, most often occurring in the morning or at night, which increases in intensity as the effect of the previously taken pain-relieving medication wears off. The similarity in clinical characteristics of MOH and CTTH often complicates the differential diagnosis of these cephalalgias.

The main diagnostic criterion for MOH is the "number of days per month with intake of pain-relieving medications". For example, the diagnosis of "combination analgesic-overuse headache" is established with regular intake of one or more such drugs ≥10 days per month for >3 months, and "NSAID-overuse headache" - with regular intake of one or more NSAIDs ≥15 days per month for >3 months [1]. The highest risk of MOH is observed with the use of pain-relieving medications containing narcotic components (codeine, etc.), barbiturates, and caffeine** [11, 12, 13]. Instrumental diagnostic methods are not used for diagnosing MOH due to their lack of diagnostic value [14, 15].

2.1 Complaints and Anamnesis

The main complaints of a patient with tension-type headache are recurrent episodes of bilateral, diffuse, pressing, and non-pulsating headache resembling a "helmet" or "band" in the frontal, temporal, parietal, or possibly occipital region or the entire head, of mild to moderate intensity (4–7 points on the visual analogue scale (VAS) for pain (Appendix G2)). The headache is not aggravated by routine physical activity; tension-type headache is not characterized by concomitant symptoms, although mild nausea and decreased appetite are possible. Photophobia and phonophobia are rarely observed in tension-type headache and do not develop simultaneously, unlike in migraine [1]. Headache episodes last from 30 minutes to several days; in CTTH, headache may be present throughout the day with periodic exacerbations and relief of pain.

Episodes of headache (HA) are triggered by psychological or postural tension of the head and neck, and are relieved by psychological relaxation and/or relaxation of the pericranial muscles [2, 6, 8]. Therefore, the frequency of pain episodes may increase during periods of emotional stress and intensive work associated with strain on the muscles of the head, face, and neck, and conversely, decrease with positive emotions, psychological and muscular relaxation.

Comments: comorbid disorders contribute to an increased frequency of episodes (chronicization) of TTH and require therapeutic correction. The most frequent CDs in patients with TTH are depression, anxiety disorders (including panic attacks), somatoform and senestopathic-hypochondriacal disorders, sleep disturbances, and other pain syndromes (including fibromyalgia).

2.2 Physical Examination

Clinical diagnosis of TTH, along with the analysis of complaints and anamnesis, includes a neurological examination.

Comments: in the typical course of TTH, no pathological changes are found in the neurological status. There may be depressed mood, signs of increased anxiety, autonomic disorders (hyperventilation, palmar hyperhidrosis, signs of increased neuromuscular excitability in the form of Chvostek's sign grade I–III), and the patient's inability to achieve psychological and muscular relaxation.

Comments: synonyms for muscle tension: pericranial muscle dysfunction (PMD), muscle-tonic syndrome (MTS), muscle spasm. Palpation should be performed with small rotational movements using the second and third fingers with pressure applied bilaterally to the temporal, masseter, sternocleidomastoid, and trapezius muscles, as well as the posterior neck muscle group (splenius, inferior oblique). If painful tension is detected in one or more muscle groups, an appropriate diagnosis should be made, for example: "Chronic tension-type headache with pericranial muscle tension" [1].

2.3 Laboratory Diagnostics

Since the diagnosis of TTH is clinical, laboratory methods are not mandatory.

Comments: laboratory tests are not informative in the diagnosis of TTH because they do not reveal changes specific to this disease.

2.4 Instrumental Diagnostics

Since the diagnosis of TTH is clinical, instrumental examinations are not mandatory.

Comments: instrumental examinations are not informative in the diagnosis of TTH because they do not reveal changes specific to this disease.

Comments: an atypical course of TTH is defined as failure to meet 2 or more diagnostic criteria of the ICHD-3. Warning symptoms are listed in Table 5. If technical capabilities are lacking or there are medical contraindications to performing an MRI, it is indicated to perform A06.23.004 Computed tomography of the brain, A06.12.056 Computed tomography angiography of cerebral vessels, A06.23.004.007 Computed tomography of cerebral vessels with intravenous bolus contrast enhancement.

Table 5. List of warning symptoms – "red flags" in patients with headache [8, 10 - 14]

2.5 Other Procedures

2.5.1 Headache diary

To determine the number of days with headache per month (establishing the TTH subtype) and the number of days taking analgesics, it is recommended that the patient maintain a headache diary (Appendix A3.1) [2, 5, 8]. Maintaining a headache diary for 1 to 3 months helps the patient and physician distinguish one headache variant from another (e.g., a migraine attack from an episodic TTH episode), determine the number of days with headache per month, and the number of days with analgesic intake per month.

2.5.2 Differential Diagnosis

Comments: to facilitate the differential diagnosis of TTH and migraine, it is advisable for the patient to keep a headache diary. Differential diagnosis with the listed secondary headache forms requires appropriate additional investigations. If technical equipment is unavailable or there are medical contraindications to MRI, performing A06.23.004 Computed tomography of the brain is indicated.

Comments: difficulties in the differential diagnosis of CTTH and CM arise because the leading clinical manifestations of CM include both persistent frequent migraine attacks and TTH-like "background" pain. In this case, reliance should be placed on early medical history: unlike patients with CTTH, patients with CM present at disease onset with typical episodic migraine attacks and other features characteristic of migraine (family history, typical migraine triggers, headache relief during pregnancy) [3, 9, 10].

Comments: examples of combined diagnoses: 1. "Episodic tension headache with pericranial muscle tension. Migraine with aura", 2. "Chronic tension headache with pericranial muscle tension. Migraine without aura. Medication-overuse headache (combination analgesics)".

3. Treatment, including drug and non-drug therapies, diet therapy, and pain management

The management of patients with TTH involves three approaches: behavioral therapy, acute treatment of pain episodes, and prophylactic (course) treatment [2, 8, 10, 13].

The primary goals of TTH treatment are to reduce the frequency and intensity of pain episodes and to improve patients' quality of life. TTH treatment strategies include normalizing the patient's emotional state, relieving muscle tension, correcting comorbid disorders (primarily psychiatric disorders), and, if necessary, overcoming medication overuse / treating medication-overuse headache.

3.1 Behavioral therapy

Comments: key principles of behavioral therapy include:

1. explaining to patients the benign nature of TTH and its mechanisms of occurrence, and reassuring them against the presence of an organic cause of the headache;

2. justifying the inappropriateness of additional investigations (except in cases of suspected secondary/symptomatic headache);

3. explaining the role of TTH episode triggers: emotional and muscle tension, comorbid emotional disorders (anxiety, depression, and phobic disorders);

4. emphasizing the need for training in psychological and muscular relaxation;

5. discussing the role of risk factors for TTH frequency increase (chronicisation): medication overuse, muscle tension, emotional factors; patients with CTTH who overuse analgesics should be advised on the necessity of discontinuing these medications;

6. explaining treatment goals, mechanisms of action of prophylactic drugs, and the benefits of non-pharmacological methods.

3.2 Acute treatment of headache episodes

To abort TTH episodes, analgesics should be used (Table 6).

Table 6. Medicines for aborting a TTH attack

Comments: a 500 mg single dose is also frequently used.

Comments: combination with caffeine increases the efficacy of medications containing ibuprofen [26] and paracetamol [20, 23–25], but may also increase the risk of MOH in patients with tension headache. Therefore, combination drugs containing caffeine have a grade B recommendation.

When prescribing analgesic medications to patients with tension headache, the following principles must be applied:

1. the choice of analgesic medication should be based on its efficacy and potential side effects;

2. NSAIDs are more effective than acetylsalicylic acid**, which, in turn, is more effective than paracetamol**;

3. a more rapid effect is achieved by using soluble formulations of analgesic medications (ibuprofen**, ketoprofen**, acetylsalicylic acid**).

4. the use of NSAIDs is possible in patients with episodic TTH (ETTH) when headache episodes occur no more than 2 times a week (up to 10 headache days per month); as the frequency of use of these agents increases, their effect decreases and the risk of MOH develops;

5. when using NSAIDs, potential side effects must be taken into account, primarily gastrointestinal effects and the risk of bleeding;

6. the use of combination products containing acetylsalicylic acid + caffeine + paracetamol is more effective than monotherapy, but using these drugs for more than 8 days per month carries the risk of developing MOH.

3.3 Preventive treatment

Prophylactic therapy for TTH aims to reduce headache frequency, decrease the number of analgesics taken, and improve the patient's quality of life.

Comments: general recommendations for the management of patients with TTH include:

1. the patient should be informed about the rationale for antidepressant therapy, mechanisms of action, and potential side effects of the prescribed medications—for example, that antidepressants possess not only antidepressant but also analgesic properties;

2. to minimize side effects, a slow (gradual) dose titration is advisable;

3. prolonged use of the chosen prophylactic agent at an adequately tolerated dose for 6 to 12 months is necessary;

4. if no effect is observed within 3 months, the chosen prophylactic agent should be discontinued and another drug or combination of agents should be used;

5. the total duration of prophylactic therapy is 3 to 6 months for episodic TTH and up to 12 months for chronic TTH.

Comments: after 3 months of prophylactic therapy, the number of headache days per month with successful treatment should decrease by 50% from baseline.

Table 7. Medications for the prophylactic treatment of tension-type headache

Comments: the effect of antidepressants is due to their intrinsic analgesic action resulting from the enhancement of antinociceptive system activity [3, 6]. The analgesic effect appears earlier than the proper antidepressant effect and is observed when antidepressants are used at lower doses.

Comments: treatment with #amitriptyline** is initiated at low doses (5 - 10 mg daily), after which the daily dose is increased (titrated) by 5 - 10 mg daily every week until a clinical effect or adverse events occur; the average effective dose of #amitriptyline** is 50 - 75 mg daily (ranging from 25 to 150 mg daily). To facilitate tolerability and in patients with concomitant sleep disturbances, the larger portion of the #amitriptyline** dose should be taken 1 - 2 hours before bedtime. It is important to explain to the patient that although #amitriptyline** is an antidepressant, it also exhibits pronounced analgesic efficacy and high effectiveness in treating TTH [2, 8, 28].

Comments:

1. if there is no effect after 3 months of taking a therapeutic dose of #amitriptyline** or in case of its poor tolerability, clomipramine**, #venlafaxine, or #mirtazapine may be used [29 - 33]; the efficacy of other antidepressants in TTH prophylaxis is insufficiently proven;

2. antidepressants from the selective serotonin reuptake inhibitor (SSRI) group have less pronounced analgesic properties and lack a sufficient evidence base in the treatment of chronic TTH.

Comments: treatment with #tizanidine can be initiated at 2 mg 3 times daily, gradually increasing the dose to 4 mg 3 times daily and 6 mg 3 times daily if necessary.

Comments: the duration of muscle relaxant therapy does not exceed 2 months (on average 3 - 4 weeks). Since the clinical effect of these drugs appears faster than that of antidepressants, prescribing combination therapy—using an antidepressant together with a muscle relaxant—may help increase patient adherence to treatment.

3.4 Features of treatment for TTH combined with medication-overuse headache (MOH)

Patients with a combination of chronic TTH and medication-overuse headache (MOH) require MOH treatment, which includes behavioral therapy, withdrawal of overused medications, management of withdrawal headache (detoxification), and prophylactic treatment of TTH.

Comments: patients with frequent episodic TTH (headache frequency of 8 days or more per month and about 8–10 days per month with analgesic use) represent a risk group for developing MOH. In at-risk patients, preventing medication overuse via behavioral therapy is more effective than treating already established MOH [39].

The main strategies for preventing MOH development in the risk group include: informing patients about safe dosing regimens for acute headache medications (no more than 2 days per week – and no more than 8 days per month) and controlling other risk factors for TTH chronicization (emotional stress, anxiety, depression, pericranial muscle tension). Patients should be explained that overuse of acute TTH medications contributes to an increased frequency of headache days—i.e., chronicization of TTH and development of MOH—and that the only path to headache relief is a significant reduction or temporary withdrawal of the overused drug(s).

Behavioral therapy (advice on restricting/discontinuing "culprit" medications) has insufficient efficacy in patients with comorbid psychiatric disorders (depression, anxiety) who abuse opioids, anxiolytics, barbiturates, or multiple pharmacological groups with analgesic effects simultaneously, as well as in those with a history of failed attempts to discontinue abused drugs [11, 40 - 42].

Comments: both complete and partial discontinuation of the abused drug(s) can be used. The number of days with intake of any analgesic medications should not exceed 2 per week (8 per month). Analgesic discontinuation can be performed on an outpatient basis; discontinuation of opioids and analgesics combined with psychotropic drugs, including in combination with benzodiazepine derivative abuse, should be performed in an inpatient/day hospital setting [40, 43].

Comments: treatment of TTH and other clinical manifestations of the withdrawal period (detoxification) should be carried out during the first two weeks of the discontinuation period. The choice of drugs is determined by clinical manifestations (for example, in the presence of vomiting, it is advisable to use antiemetic drugs (ATC: Gastrointestinal motility stimulators)).

Patients abusing opioids, benzodiazepine derivatives, or barbiturates need monitoring of blood metabolic parameters, blood pressure, and fluid replacement (including drinking plenty of fluids).

During the discontinuation of abused drugs in patients with a combination of TTH and MOH, systemic corticosteroids, selective NSAIDs, and anxiolytics can be used orally or parenterally to treat "rebound" TTH and other clinical manifestations of withdrawal syndrome (Table 8).

Table 8. Medications recommended for the treatment of withdrawal headache and other withdrawal symptoms in patients with MOH

Comments: for the use of #prednisolone**, there are 2 oral regimens: 100 mg for 5 days [45] or 60 mg for 2 days, 40 mg for 2 days, 20 mg for 4 days [43].

Comments: during the discontinuation of habitual "culprit" analgesics, classes of drugs that the patient has not previously abused can be used as alternative analgesic medications. For example, in case of opioid analgesic abuse, NSAIDs such as #celecoxib, naproxen, or lornoxicam may be recommended.

Comment: preventive therapy for chronic TTH combined with MOH is preferably initiated together with the discontinuation of the abused drug(s) and treatment of withdrawal headache, although it can also be prescribed before the discontinuation of abused drugs [38-41]

Comment: in clinical practice, other antidepressants can also be used, but their efficacy in MOH has not been proven.

General practitioners, internists, and neurologists who experience difficulties in managing patients with MOH should briefly explain to the patient the negative role of medication overuse in increasing the frequency of headaches, inform them of the need for complete or partial cessation of abused drugs, and refer the patient to a headache specialist or a specialized headache (pain) treatment center [8, 11].

3.5 Other treatments

3.5.1 Non-pharmacological treatment

To increase the efficacy of preventive therapy for TTH, especially in patients with the chronic form, it is advisable to combine pharmacological treatment with non-pharmacological methods (Table 8) [48 — 68].

Table 8. Non-pharmacological treatment methods in patients with tension-type headache

* - BFB - electromyographic biofeedback training of the scalp and neck muscles

** - Cognitive behavioral therapy

Comment. Experimental studies [60] demonstrate an increase in the activity of antinociceptive systems with an increase in plasma β-endorphin levels during the use of the BFB method. A series of repeated BFB sessions (from 8 to 15) can significantly reduce the frequency of headache episodes and anxiety levels in patients with TTH. Since the availability of BFB in the Russian Federation is limited, other methods should be used more widely (Table 8).

Comment: CBT is aimed at helping the patient become aware of their condition, reducing pain catastrophizing, forming positive coping strategies for TTH and emotional stress, and mastering stress management programs [52, 53].

To increase the efficacy of preventive therapy for TTH, it is advisable to use physiotherapeutic methods.

Comment. PIR is one of the most effective physiotherapeutic approaches used for the treatment of patients with TTH, both as a standalone method and in combination with pharmacotherapy [54 - 56].

In the presence of trigger points in tense pericranial and neck muscles in patients with TTH accompanied by pericranial muscle dysfunction, dry needling of trigger points may be used [68].

Comments: the exercise therapy program (A19.23.002 Exercise therapy for central nervous system and brain disorders; A19.23.002.001 Exercise therapy for central nervous system and brain disorders in a swimming pool; A19.23.002.025 Exercise therapy using apparatus and training devices for central nervous system and brain disorders; A19.24.001 Exercise therapy for peripheral nervous system disorders) includes exercises to strengthen deep neck muscles, coordination, muscle stretching, posture correction, breathing exercises, as well as aerobic exercise [65], strength training [57], and yoga [58]. As a rule, at least 10 sessions are recommended.

Comments: in the presence of trigger points in tense pericranial and neck muscles in patients with TTH accompanied by pericranial muscle dysfunction, dry needling of trigger points may be used [4, 6, 68].

4. Medical Rehabilitation and Sanatorium-Resort Treatment

Rehabilitation measures for patients with TTH have not been developed.

4.1. Sanatorium-resort treatment

Not developed.

5. Prevention and Dispensary Observation

Comments: explanatory work can be carried out by general practitioners, internists, and neurologists whom patients with TTH consult. Patients should be advised to avoid prolonged work in a forced posture with static tension of pericranial muscles, conflict and stressful situations, and excessive intake of analgesic drugs, as well as to receive training in psychological and muscle relaxation.

6. Organization of Medical Care

Indications for emergency hospitalization of a patient in the neurological department:

1. Headache accompanied by altered consciousness

2. Headache accompanied by fever and meningeal signs

3. Headache with progressive focal neurological symptoms

4. Headache with progressive general cerebral symptoms

5. Thunderclap headache

Indications for planned hospitalization of a patient in the neurological department:

1. Progressive headache

2. Refractory headache

3. Headache associated with the overuse of opioids, spasmolytics, psychotropic drugs, and analgesics in combination.

Indications for discharging patients from the neurological department:

1. Relief of headache

2. Reduction of headache to 3–4 points on the visual analogue scale

3. Successful replacement of the overused drug with adequate pharmacotherapy

7. Additional Information

The course of the disease in patients with TTH can significantly worsen in the absence of treatment and with inadequate treatment.

One of the prerequisites for prescribing ineffective treatment is establishing false, so-called "organic" diagnoses instead of the diagnosis of "TTH" [2, 8, 70]. Examples of erroneous diagnoses masking the TTH diagnosis: discetulatory encephalopathy, cervical spine osteochondrosis; vegetative-vascular dystonia with cephalgic syndrome; hypertension-hydrocephalic syndrome with cephalgic syndrome, headache associated with arterial hypertension, cervicogenic headache.

The establishment of false diagnoses is generally caused by the misinterpretation of instrumental study results: detected non-specific changes are regarded by physicians as signs of organic brain or cerebral vascular lesions, which serves as the basis for an erroneous diagnosis [2, 8, 70].

Establishing an incorrect diagnosis, in turn, leads to the choice of incorrect treatment tactics, most often to the prescription of psychostimulants and nootropic drugs, which have no evidence base in the treatment of TTH and do not relieve the patients' condition [2, 8, 70]. Thus, the listed diagnostic and treatment errors can contribute to the chronification of TTH and further deterioration of patients' quality of life.

For example, a slight decrease in the linear blood flow velocity on ultrasound dopplerography (UDG) of craniovertebral arteries is often the basis for erroneous diagnoses of "dyscirculatory encephalopathy" or "chronic cerebral ischemia", a slight expansion of subarachnoid spaces during magnetic resonance imaging (MRI) of the brain is the basis for the diagnosis of "hydrocephalic syndrome with cephalgic syndrome", and signs of degenerative changes in the cervical spine are the basis for the diagnosis of "cervical spine osteochondrosis with cephalgic syndrome".

If the diagnosis of "dyscirculatory encephalopathy" is established instead of the diagnosis of "CTTH", the patient will be recommended psychostimulants and nootropic drugs rather than antidepressants, which have proven efficacy in the treatment of TTH [8, 70].

7.1 Assessment of therapeutic efficacy in a patient with headache

Criteria for Evaluating the Quality of Medical Care

Quality criteria for specialized medical care for adults with tension-type headache [2, 6, 10].

References

Appendix A1. Working Group Composition

Yulia E. Azimova, D.Sc. in Medicine, neurologist at the University Headache Clinic. Leading Researcher at the Research Institute of General Pathology and Pathophysiology of the Ministry of Science and Higher Education. Member of the Russian Headache Research Society. Member of the European Headache Federation.

Vera V. Alferova, D.Sc. in Medicine, Chief Researcher at the Research Laboratory of Cerebral Vascular Diseases, Pirogov Russian National Research Medical University of the Ministry of Health of the Russian Federation.

Alexander V. Amelin, D.Sc. in Medicine, Professor at the Department of Neurology, Head of the General Neurology Division at the Research Institute of Neurology of the National Medical Research Center, Pavlov First Saint Petersburg State Medical University of the Ministry of Health of the Russian Federation. Head of the Headache Committee of the Russian Interregional Pain Society, member of the Russian Headache Research Society.

Ada R. Artemenko, D.Sc. in Medicine, Professor at the Department of Nervous Diseases of the Institute of Professional Education, I.M. Sechenov First Moscow State Medical University of the Ministry of Health of Russia (Sechenov University) and the Center for Interdisciplinary Dentistry and Neurology, Moscow. Member of the Russian Headache Research Society, member of the European Headache Federation, member of the International Headache Society, member of the European Academy of Neurology.

Leila R. Akhmadeeva, D.Sc. in Medicine, Professor at the Department of Neurology, Bashkir State Medical University of the Ministry of Health of the Russian Federation. Member of the Russian Headache Research Society, Head of the Bashkir Branch, member of the Interregional Association of Botulinum Therapy Specialists.

Evgenia V. Ekusheva, D.Sc. in Medicine, Head of the Department of Nervous Diseases and Neurorehabilitation at the Academy of Postgraduate Education, Federal Research and Clinical Center of the Federal Medical-Biological Agency, Academician Alexander Wayne Headache and Autonomic Disorders Clinic, GUTA Clinic, Moscow. Member of the Russian Pain Society. Member of the Headache and Facial Pain Committees of the Russian Interregional Pain Society. Member of the Interregional Association of Botulinum Therapy Specialists. Member of the European Headache Federation and the International Headache Society.

Yulia V. Karakulova, D.Sc. in Medicine, Professor at the V.P. Pervushin Department of Neurology, Perm State Medical University of the Ministry of Health of the Russian Federation. Member of the Russian Headache Research Society.

Marina I. Koreshkina, D.Sc. in Medicine, Head of the Headache Treatment Center at Adel Med Medical College Clinic LLC, Saint Petersburg, editor of the "All About Headaches" portal. Member of the Russian Headache Research Society. Member of the International Headache Society.

Olga V. Kurushina, D.Sc. in Medicine, Head of the Department of Neurology, Neurosurgery, and Medical Genetics, Volgograd State Medical University of the Ministry of Health of the Russian Federation. Board Member of the All-Russian Society of Neurologists. Member of the Russian Headache Research Society.

Nina V. Latysheva, D.Sc. in Medicine, Professor at the Department of Nervous Diseases of the Institute of Professional Education, I.M. Sechenov First Moscow State Medical University of the Ministry of Health of Russia (Sechenov University) and Academician Alexander Wayne Headache and Autonomic Disorders Clinic, Moscow. Member of the Russian Headache Research Society. Member of the European Headache Federation. Member of the International Headache Society.

Elena R. Lebedeva, D.Sc. in Medicine, Professor at the Department of Hospital Therapy, Ural State Medical University of the Ministry of Health of the Russian Federation, Head of the "Europe-Asia" International Headache Center, Yekaterinburg. Member of the Russian Headache Research Society. Member of the International Headache Society. Member of the European Headache Federation. Member of the Headache Section of the European Academy of Neurology. Russian representative in the Education Committee of the European Academy of Neurology.

Margarita V. Naprienko, D.Sc. in Medicine, Professor at the Department of Sports Medicine and Medical Rehabilitation of the N.V. Sklifosovsky Institute of Clinical Medicine, I.M. Sechenov First Moscow State Medical University of the Ministry of Health of Russia (Sechenov University). Chief Medical Officer of the Academician Alexander Wayne Headache and Autonomic Disorders Clinic. Member of the Russian Headache Research Society. Member of the Interregional Association of Botulinum Therapy Specialists. Member of the European Headache Federation.

Vera V. Osipova, D.Sc. in Medicine, neurologist at the University Headache Clinic. Leading Researcher at the Solovyov Research and Practical Center for Mental Health of the Moscow Healthcare Department. Member of the Russian Headache Research Society (RHRS). Member of the European Headache Federation (EHF). Member of the Lifting the Burden (LTB) campaign. Member of the Classification Committee of the International Headache Society (ICHD IHS).

Nikolay A. Pavlov, Ph.D. in Medicine, Leading Researcher at the Research Laboratory of Cerebral Vascular Diseases, Pirogov Russian National Research Medical University of the Ministry of Health of the Russian Federation.

Vladimir A. Parfenov, D.Sc. in Medicine, Professor, Head of the Department of Nervous Diseases and Neurosurgery of the Institute of Clinical Medicine, I.M. Sechenov First Moscow State Medical University of the Ministry of Health of Russia (Sechenov University). Board member of the All-Russian Society of Neurologists, board member of the National Stroke Association, member of the "General Neurology" panel of the European Academy of Neurology.

Andrey P. Rachin, MD, PhD, Professor, President of the National Association of Experts in Comorbid Neurology. Board Member of the All-Russian Society of Neurologists. Presidium Member and Auditor of the Russian Headache Research Society (RHRS).

Alexey V. Sergeev, PhD, Associate Professor at the Department of Nervous Diseases and Neurosurgery, Institute of Clinical Medicine, FSAEI HE I.M. Sechenov First Moscow State Medical University of the Ministry of Health of the Russian Federation (Sechenov University). Member of the All-Russian Public Organization «Russian Headache Research Society» (RHRS). Member of the All-Russian Public Organization «Russian Pain Society» (RPS) and Head of the Pediatric Pain Study Committee of the RPS. Member of the European public organization «European Headache Federation». Russia Representative in the international public organization «International Headache Society».

Kirill V. Skorobogatykh, PhD, Neurologist, Head of the University Headache Clinic (Moscow). Member of the All-Russian Public Organization «Russian Headache Research Society». RF Representative in the European public organization «European Headache Federation». Member of the Education Committee of the international public organization «International Headache Society».

Gyuzal R. Tabeeva, MD, Professor at the Department of Nervous Diseases and Neurosurgery, Institute of Clinical Medicine, FSAEI HE I.M. Sechenov First Moscow State Medical University of the Ministry of Health of the Russian Federation (Sechenov University). President of the All-Russian Public Organization «Russian Headache Research Society». Member of the European public organization «European Headache Federation».

Elena G. Filatova, MD, Professor at the Department of Nervous Diseases, Institute of Professional Education, FSAEI HE I.M. Sechenov First Moscow State Medical University of the Ministry of Health of the Russian Federation (Sechenov University) and Academician Aleksandr Wayne Headache and Autonomic Disorders Clinic, Moscow. Member of the All-Russian Public Organization «Russian Headache Research Society». Member of the European public organization «European Headache Federation».

Conflict of interest: none.

Appendix A2. Methodology for Developing Clinical Guidelines

Target audience for these clinical guidelines:

1. neurologists*, general practitioners, family physicians;

2. medical students, residents, postgraduate students;

3. faculty members, researchers;

*including specialists in the diagnosis and treatment of headache (cephalologists).

In these clinical guidelines, all information is ranked by the level of validity (evidence) depending on the quantity and quality of studies conducted on the given issue (Tables 1–3).

Table A1. Scale for assessing levels of evidence (LoE) for diagnostic methods (diagnostic interventions)

Table P2. Scale for assessing levels of evidence (LE) for prevention, treatment, and rehabilitation methods (preventive, therapeutic, and rehabilitative interventions)

Table А3. Grading system for levels of convincing evidence (LCE) for preventive, diagnostic, treatment, and rehabilitation methods (interventions)

Procedure for updating clinical guidelines.

The mechanism for updating clinical guidelines provides for their systematic revision at least once every three years, as well as upon the emergence of new evidence-based medicine data on the diagnosis, treatment, prevention, and rehabilitation of specific diseases, or in the presence of justified additions/comments to previously approved clinical guidelines, but no more frequently than once every 6 months.

Appendix A3. Reference Materials

These clinical guidelines were developed taking into account the following regulatory legal documents:

1. Federal Law No. 323-FZ of November 21, 2011, «On the Fundamentals of Protecting the Health of Citizens in the Russian Federation».

2. Procedure for the provision of medical care to the adult population for diseases of the nervous system (Order of the Ministry of Health of the Russian Federation No. 926n of November 15, 2012).

3. Order of the Ministry of Health of the Russian Federation No. 103n of February 28, 2019, «On Approval of the Procedure and Timeframes for the Development of Clinical Guidelines, Their Revision, the Standard Form of Clinical Guidelines, and Requirements for Their Structure, Composition, and Scientific Validity of Information Included in Clinical Guidelines».

4. State Register of Medicines https://grls.rosminzdrav.ru/GRLS.aspx

Appendix A3.1. Headache diary

DO NOT FORGET TO BRING THE COMPLETED DIARY TO YOUR APPOINTMENT WITH YOUR PHYSICIAN!

DIARY COMPLETION INSTRUCTIONS

Before your consultation at the Headache Center, it is very important that you fill out this diary daily. The information you record in the diary will help the physician accurately determine the diagnosis and severity of your headache (HA), as well as promptly prescribe the optimal treatment for you.

At the top, write your full name, date of birth, and the date you started filling out the diary. Then, opposite Question 1 in the 1st column, write the date (day of the month) when the diary is filled out. You can enter dates in all columns right away, as you will need to fill out the diary daily.

Please fill out the diary every evening before going to bed by checking [Ö] the boxes (1) in the vertical column. This data provides summarized information about any headache(s) if it (they) occurred on that day. If you did not have a headache on that day, answer only Questions 2 and 15. If you have finished filling out one page of the diary, please continue on the next page (several copies are attached).

Instructions for answering the questions are provided below.

1. Indicate only the day (e.g., 12); month and year do not need to be specified.

2. Check «Yes» or «No» in the boxes opposite all questions, or proceed directly to Question 15 (if there was no headache on that day).

3. Indicate the time (hour in 24-hour format) when you first noticed the onset of the headache. If you woke up already with a headache, indicate the waking time. (If the morning headache is a continuation of the evening one, put an X in the column).

4. Indicate the time (hour and minutes in 24-hour format) when the headache completely stopped. If the headache was still present on that day before going to bed, leave the box blank. If the headache was absent in the morning, indicate the bedtime. If the headache persisted in the morning, put an X in that day's column, as well as an X in the Question 3 column on the next page. Continue your entries on the next day as usual.

5. Some people experience certain visual disturbances within 1 hour before the onset of a headache. These may include flashes of light, luminous zigzag lines, «blind» spots, or «black holes» that persist even when eyes are closed. Check «Yes» if you experienced something similar, or «No» if such phenomena did not occur. If you were simply bothered by light (see Question 12) and nothing else, check «No».

6. Check the box corresponding to the localization of the headache (predominantly on one side of the head or on both sides).

7. Although there are many descriptions of headache characteristics, most headaches are either «throbbing» (pain worsens in time with the heartbeat) or «pressing» (like a «tight band»). Check the characteristic that best reflects the type of your headache.

8. Some types of headaches worsen even with minor physical exertion (e.g., climbing stairs) or force a person to avoid such activity. Check «Yes» if this applies to your headache, and «No» if this is not characteristic of you.

9. Headache intensity (strength) is an important component of the diagnosis. Rate the strength of your headache by checking the appropriate box if: a «mild» headache is a headache that does not disrupt normal activities (i.e., your work capacity and normal activity), a «moderate» headache makes normal activities difficult but does not completely prevent them, and finally, a «severe» pain is a headache that completely disrupts your normal activity. Try to rate the headache intensity throughout the day as a whole. For example, if the pain was mild in the first half of the day and then became severe, check the «moderate» box. However, if the pain was very intense for almost the entire day, check «severe».

10. Check «No» if you had no nausea at all during the day. If you experienced mild nausea that hardly bothered you, did not cause belching or retching, check «mild», or in case of more pronounced nausea, «marked».

11. Check «Yes» or «No». Belching and retching are not considered vomiting.

12. The question concerns normal daylight or indoor light, not very bright light. Check «Yes» if normal light bothered you or you tried to avoid it by darkening the room or wearing sunglasses. Otherwise, check «No».

13. The question concerns normal noise, not very loud sounds. Check «Yes» if the noise bothered you or you tried to avoid it by secluding yourself in a quiet room. Otherwise, check «No».

14. Please list any causes (factors) that you think might have triggered the headache. Perhaps you ate, drank, or did something (e.g., skipped lunch, spent a sleepless night, did physical work) or there were other causes (weather change, stress, menstruation).

15. Please list the names of any medications (tablets, suppositories, injections, nasal sprays) you took for headache or any other pain. For each medication, indicate the number of doses taken, as well as the time of administration (hours in 24-hour format) for each medication. Do not list medications taken for other indications.

Full Name:___________________________________________________________________________Date of Birth (D/M/Y)_____________

Start of diary completion:_________________ End of diary completion _________________

Read the instructions carefully before filling out the diary! Fill out one column every evening, checking the appropriate boxes.

Appendix B. Physician Action Algorithms

Appendix C. Patient Information

What is tension-type headache?

"My headache can last for several days; it feels as if I'm wearing a tight cap, a band, or a helmet; it feels more like tension or pressure rather than actual pain. These sensations do not completely disrupt, but significantly limit my daily activities."

Tension-type headache (TTH) is the most common form of headache that anyone can experience from time to time. Although TTH poses no threat to life and health, it can significantly impair daily activities. Individuals with frequent episodes of TTH should be monitored by a physician.

Who suffers from TTH?

Most people experience episodes of TTH from time to time, with women being affected more often than men; TTH can also occur in childhood.

What types of TTH are there?

Episodic tension-type headache (ETTH) is often described as a "normal" or "ordinary" headache. ETTH is characterized by episodes of pain lasting from 30 minutes to several days. The frequency of TTH episodes can vary, both among different individuals and in the same person at different stages of life.

About 3 out of 100 people experience TTH most of the time (more days with headache than days without). This is chronic tension-type headache (CTTH), which is a subtype of chronic daily headache. In some cases, TTH is present constantly; it may be mild, but it never completely resolves. This clinical course of TTH causes ongoing stress and leads to a significant decrease in quality of life.

What are the symptoms of TTH?

TTH is typically described as pressing or tightening, like a tight band or a snug cap around the head. The pain is usually bilateral and generally mild to moderate in intensity, but it can sometimes be severe enough to impair daily activities. In most cases, TTH is not accompanied by associated symptoms, although some individuals may have sensitivity to bright light or loud sounds; appetite may occasionally be reduced.

What causes TTH?

TTH is believed to be associated with tension in the muscles and ligaments of the head and neck. Muscle contraction is accompanied by impaired blood supply and the release of "pain-inducing" substances into the bloodstream, which causes the feeling of tightening pain. There are many causes of TTH, but several factors are the most significant:

-- Emotional tension: high anxiety, stress

-- Physical strain in the muscles of the scalp and neck, which may be caused by working in an awkward posture, such as prolonged computer work, an awkward posture when lifting heavy objects, and other similar strains. In turn, emotional tension sustains muscle spasm.

What can you do to help yourself?

1. Relaxation: taking breaks during prolonged work, therapeutic head and neck massage, warm baths, outdoor walks, exercises, fitness.

2. Stress management. If your work involves emotional stress or you are facing an unavoidable stressful situation, begin practicing breathing and relaxation exercises; this will help prevent TTH. Use commercially available audio and video recordings to learn relaxation techniques.

3. Regular exercise. TTH is more common in individuals who do not engage even in light physical activity. Take walks in the fresh air more often, take the stairs instead of the elevator, and do gymnastics so that it becomes an integral part of your life.

4. Treatment of depression. If you feel low or depressed most of the time, be sure to consult a doctor. Effective medications exist, and taking them for an adequate period helps reduce anxiety and improve mood.

Keeping a headache diary

Keeping a diary will help collect important information: how often you get headaches, when the headache occurs and how long it lasts, what symptoms accompany it, and how much and how often you take analgesic medications. This information is extremely valuable for establishing an accurate diagnosis, identifying headache triggers, and assessing treatment efficacy.

Take pain relievers if necessary …

Analgesic medications such as acetylsalicylic acid** or the NSAID ibuprofen** usually provide good relief for ETTH. Paracetamol** has a weaker effect.

… but not too often!

Analgesic medications only treat the symptoms of TTH, which is helpful for infrequent episodes. In the management of frequent and chronic forms of TTH, an effort should be made to target the root cause of the headache (stress, emotional disturbances, muscle tension). Always follow the drug package insert carefully. You should not take analgesics too often, as this can lead to an increased headache frequency and the development of medication-overuse headache (MOH). To avoid this, do not take analgesic medications more than 2 days per week.

What other treatments are available?

If you have frequent or chronic TTH, taking analgesic medications is not the solution. On the contrary, with their frequent use, headaches will occur more often and become more severe. In this case, preventive (prophylactic) therapy is indicated. Unlike the as-needed use of analgesics, preventive treatment must be taken daily, which is due to the different mechanisms of action of these drug classes. Preventive therapy aims to reduce your pain sensitivity and prevent headache episodes from developing.

Your physician will recommend medications for preventive therapy and advise you of potential side effects. Most of these drugs were originally developed to treat other conditions, so you should not be surprised if you are prescribed an antidepressant, an anticonvulsant, or a muscle relaxant. Medications from these classes are effective in preventing TTH episodes.

When prescribed one or more medications, strictly follow the dosing instructions. Studies have shown that the most common cause of insufficient treatment efficacy is poor adherence to the therapy regimen.

Because prolonged work in an awkward posture or postural defects resulting in muscle tension can cause TTH, your doctor may prescribe physical therapy for the head and neck region. For some individuals, physical therapy is very helpful. Non-pharmacological treatments also include transcutaneous electrical nerve stimulation (as a pain relief modality), relaxation therapy, biofeedback, acupuncture, and yoga. These methods are not always effective and are not suitable for every patient. Your doctor will provide advice and recommendations on the use of these techniques.

Botulinum toxin is not effective in the treatment of TTH.

Will the treatment be effective?

If the cause of the headache is identified and eliminated, episodic TTH rarely becomes a serious problem. Once the underlying cause is resolved, ETTH typically resolves on its own, and there is no need for further therapy. However, for some patients, especially those with CTTH, many treatments prove to be only partially effective or completely ineffective. In such cases, it is necessary to consult a headache specialist (headache neurologist) or visit a specialized headache center that offers a comprehensive range of therapies for TTH.

Do you need additional diagnostic workup?

Currently, there are no diagnostic tests that can confirm a diagnosis of TTH. Diagnosis is based on your description of the headache characteristics and associated symptoms, with the mandatory requirement of a normal physical and neurological examination. Try to describe your headache to your doctor in as much detail as possible. It is crucial to inform your doctor about how often and in what quantities you take analgesics or other medications for headaches. Additionally, the doctor may palpate the muscles of your head and neck to evaluate muscle tenderness and pericranial muscle tension.

In TTH, neuroimaging of the brain is generally uninformative. However, if your doctor is unsure of the diagnosis, they may order additional investigations, including neuroimaging (CT or MRI), to rule out secondary causes of headache. Usually, this is not frequently necessary. If your doctor has not ordered additional tests, it means they are confident in the diagnosis and further imaging would not alter the management plan.

Appendix G. Assessment Scales, Questionnaires, and Other Evaluation Tools

Appendix G1. Visual Analogue Scale for pain

Russian name: Visual Analogue Scale for Pain (VAS)

Original name: Visual Analogue Scale (VAS) [71-73]

Type: rating scale

Purpose: intended for measuring pain intensity (in the case of TTH – tension-type headache)

Content: VAS is a continuous scale in the form of a horizontal or vertical line 10 cm long with tick marks every 1 cm from 0 to 10, where 0 points means "no pain", and 10 points means "the worst imaginable pain."

Key (interpretation): a higher score indicates greater pain intensity.

Explanation: for example, a score of 2 to 4 points indicates mild pain intensity, 5 to 7 indicates moderate (average) intensity, 8–9 – very severe, 10 – unbearable, extremely intense pain