Chronic Headaches

What is Chronic Headaches?

Chronic headache isn’t a specific illness, but a term used to describe all long-lasting headaches. According to the International Headache Society, chronic daily headaches (CDH) are defined as having 15 or more headaches each month for at least three months. However, chronic headaches are not officially classified in the International Classification of Headache Disorders.

CDH is a broad term that includes five categories of primary and secondary headaches:

• Chronic migraine headache
• Chronic tension-type headache
• Medication overuse headache (MOH)
• Hemicrania continua
• New daily persistent headache

Chronic daily headaches can be categorized as primary or secondary, depending on their cause. Primary chronic headaches don’t have an identifiable physical cause. In this category, any headache lasting less than 4 hours is considered a ‘short headache’, while anything longer is deemed a ‘long headache.’ ‘Long headaches’ often include chronic migraines and chronic tension headaches. Secondary headaches are due to other conditions or causes, like medication overuse, brain tumors, central nervous system infections, increased brain pressure, metabolic problems, after effects of an injury, vascular issues, and structural problems.

It’s important to understand that chronic headaches are often caused by a mix of these factors and can occur over time.

What Causes Chronic Headaches?

The International Classification of Headache Disorders (ICHD) identifies over 200 different types of headaches. These are placed into three categories: primary, secondary, and painful cranial neuropathies. Within each category, there are multiple subtypes.

To be classified as a chronic headache, the condition must occur at least 15 times a month for three months or more. But each type of chronic headache has its unique characteristics.

Long-lasting primary headaches (more than four hours) include chronic migraines, tension headaches, daily persistent headaches, and hemicrania continua.

– Chronic migraines can occur on one side of the head, have a throbbing pain, are usually severe, and may come with or without an aura. It’s also possible for occasional migraines to turn into chronic ones.
– For children and teenagers, chronic migraines often affect both sides of the head, and symptoms like sensitivity to light or sound can often be noticed from their behavior.
– Chronic tension headaches affect both sides of the head, have a non-throbbing pain, and don’t have associated symptoms. One common symptom is tenderness on the skull when touched.

Persistent daily headaches begin suddenly and don’t go away within 24 hours of starting. Most patients likely never had headaches before. This kind of headache is uncommon and difficult to treat. Hemicrania continua is a headache that occurs on one side of the head, comes with physical symptoms, and doesn’t let up, but sometimes worsens. This type of headache responds well to a drug called indomethacin.

Primary headaches that last less than four hours include chronic cluster headaches, neuralgiform headache attacks, and primary stabbing headaches.

– Chronic cluster headaches don’t have any relief periods and have to occur for at least a year. They occur on one side of the head within the area of the trigeminal nerve and come with physical symptoms on that side. Patients often feel restless during these headaches.
– Short-lasting neuralgiform headaches are severe, one-sided headaches with physical symptoms. One subtype, SUNCT, has eye redness and tearing, while another subtype, SUNA, has either eye redness or tearing but not both, and may come with a runny or congested nose.
– Primary stabbing headaches can occur many times throughout the day. They cause sharp, sudden, stabbing pain in the sides of the head or around the eyes.

Secondary chronic daily headaches include headaches caused by overusing medication, infections in the brain or spinal cord, blood clots in the brain, brain tumors, increased pressure within the skull, low pressure headaches, inflammation of blood vessels, aneurysms, and leaks in the fluid that surrounds the brain and spinal cord.

– Chronic medication overuse headaches often happen alongside other acute and chronic headache types, and can increase in frequency due to overuse of pain relief medication. The ICHD further classifies this disorder based on the medications used, including NSAIDs, triptans, ergotamines, non-opioid, and opioid analgesics. If these medications are stopped, it can make the headaches worse.
– Other causes of secondary chronic headaches are not covered in this article.

Risk Factors and Frequency for Chronic Headaches

Headache disorders impact a huge number of people worldwide. These can be acute (short-term) or chronic (long-term), and they mainly affect people from their teenage years up to their fifties. Chronic headaches in particular afflict approximately 1 to 4% of the global population. This means approximately 39 million people in the United States and 1 billion people globally are impacted.

• Chronic headaches are more prevalent in women, with rates being 3 to 5 times higher than in men.
• At headache clinics, about 40% of patients are diagnosed with chronic headaches.
• Chronic migraines, a type of chronic headache, are often linked with other health issues like obesity, obstructive sleep apnea, depression, chronic pain disorders, and cardiovascular disease.
• Chronic migraine headaches also affect 7 to 17% of children and teenagers, and become more common in girls after the age of 12.

Less common is Hemicrania continua – a continuous headache that affects one side of the head. It’s more common in females, with twice as many females than males affected, and it’s most often diagnosed in people in their thirties. There’s also the chronic cluster headache, which mainly affects men but can also occur in women. Women with this type of headache often experience nausea and vomiting, and may initially be misdiagnosed with migraine headaches.

Signs and Symptoms of Chronic Headaches

Diagnosing chronic daily headaches relies heavily on a detailed medical history and physical examination. Chronic headaches are characterized by having at least 15 instances of headaches every month over a three-month period. It is essential to establish the frequency, intensity, and nature of the pain, as well as what makes it better or worse. Chronic headaches can often come with additional symptoms such as teary eyes, swollen or red eyes, drooping eyelids, pinpoint pupils, a stuffy nose, or a runny nose.

It’s also crucial to evaluate all currently taken medications, even non-prescription painkillers. Some patients may have medication-overuse headaches, which often occur alongside pre-existing headache disorders. These patients tend to rely frequently on pain medications like non-steroidal anti-inflammatory drugs (NSAIDs), triptans, ergotamines, opioids, or a variety of analgesics. Indicators of this type of headache are morning headaches, headaches that happen when medication is delayed, and a relief of pain once the medication is taken.

Additionally, the patient’s comorbidities, sleep patterns, and family history of headaches should be accounted for. It’s also necessary to rule out the presence of a secondary headache disorder based on the patient’s history and examination results.

Identifying “red flags” is crucial in diagnosing secondary headaches and determining whether further diagnostic tests are needed. Such “red flags” include:

• Being over 50 years old
• A significant change in prior headache pattern
• Intense, sudden-onset headache, akin to a “thunderclap”
• Signs of systemic illness such as fever
• Existing diseases that increase the risk of developing secondary headaches, like cancer or HIV
• Neurological symptoms
• Headaches linked to Valsalva maneuvers

Physical symptoms that might suggest causes of secondary headaches include specific neurological deficits, swelling of the optic disc, loss of peripheral vision in both eyes, loss of sight in the same visual field in both eyes, reduced visual sharpness, or increased pain when performing the Valsalva maneuver.

Primary chronic headaches usually don’t present any physical symptoms but could be accompanied by autonomic symptoms or muscle tenderness in the back of the head or neck.

Testing for Chronic Headaches

In cases of chronic primary headaches, additional tests may not always be necessary, but many doctors recommend baseline lab tests and brain scans to rule out other treatable causes.

Gathering information about the patient is also essential. Key details include age, gender, race, occupation, the onset, location, and intensity of the headache, the characteristics of the pain, how long the pain lasts, the time of the day the headache tends to start, how it has progressed since the start, how frequently the headaches occur, any potential triggers, accompanying symptoms, sleep habits, what makes it better or worse, and any medications taken to relieve the pain and their frequency.

Laboratory tests often include a complete blood count to check for infections, erythrocyte sedimentation rate (ESR) to detect inflammation that may be induced by conditions like giant cell arteritis, a metabolic panel to examine the metabolic causes of headaches, and endocrine tests to check for any abnormalities in the pituitary gland, which can also lead to headaches.

As for imaging, magnetic resonance imaging (MRI) of the brain is usually the preferred choice. A contrast study, which involves injecting a dye, may be recommended to enhance the clarity of the image and better detect any structural problems. Depending on the exact diagnosis, additional tests like a positron emission tomography (PET) scan, magnetic resonance spectroscopy (MRS), a biopsy, or a lumbar puncture (if a central nervous system infection or idiopathic intracranial hypertension is suspected) may be required.

If your headaches are brought on by excessive use of medication, the type of drug and duration of headache matter. For example, if you take ergotamine, triptans, opioids, combination analgesics, or multiple drug classes, a headache can occur if you use them for more than ten days per month for over three months. On the other hand, for drugs like Aspirin, NSAIDs, and acetaminophen/paracetamol, you can experience a headache if you use them for more than fifteen days per month for more than three months.

Treatment Options for Chronic Headaches

Treating and managing long-term headache disorders depends on the root cause, and may need a team-based approach. Patients should keep a record of their headaches and any triggers. If possible, these triggers should be avoided, or at least minimized.

Chronic Migraines:

Treatment for chronic migraines should start with the understanding that while the frequency and severity of headaches should decrease, they won’t be completely gone. It should be communicated to the patient that habits such as high caffeine intake, lack of sleep, overuse of painkillers, and existing health conditions could make their chronic migraines worse. Preventive medication treatment should be used, including beta-blockers, antiepileptic drug, and antidepressants like propranolol, topiramate, and amitriptyline. Botulinum toxin A, or Botox, is another approved treatment for chronic migraines.

The latest treatment for chronic migraines involves monoclonal antibodies that target a protein called CGRP. Drugs like erenumab, fremanezumab, and galcanezumab are approved for chronic migraines that didn’t respond to other treatments. Other drugs like triptans, steroids, NSAIDs, and opioids are often used for sudden, acute episodes, but they can cause medication-overuse headaches if used routinely. If a patient is also dealing with anxiety or depression, psychological counseling may be beneficial. Moreover, methods like spinal manipulation or trigger point treatment can be used as additional therapy options.

In extreme cases that don’t respond to medication, invasive procedures like blocking certain nerves could be tried. Deep brain stimulation is also used in some cases.

Chronic Tension Headaches:

Amitriptyline, an antidepressant, is the recommended starting treatment for chronic tension headaches. This medication not only inhibits the reuptake of serotonin and noradrenaline, it also reduces tenderness in the muscles around the head. However, it can increase the risk for heart rhythm problems, so patients should be screened for heart disorders before starting this drug. If the patient is over 40 years old, an ECG is necessary. Anticonvulsants like topiramate and gabapentin can be used as alternative treatments. Therapies such as physical therapy, acupuncture, injections, spinal manipulation or muscle relaxants, which target the potential muscular causes of tension headaches, might also be beneficial.

Mental health therapies like cognitive-behavioral therapy, biofeedback, and relaxation techniques can be especially useful if the patient is also dealing with anxiety or depression.

Medication Overuse Headaches:

Patients should be educated about how overuse of painkillers can worsen headaches. They should also be made aware of over-the-counter pain relievers. While starting the patient on preventative medication, the doctor also needs to help the patient stop using the drug that’s causing the headache. Patients may feel sick and anxious for 2 to 10 days when they stop taking the painkiller. The choice of medication to help these patients transition off the problem drug varies. But, the medication selected should be different from the one causing the problem.

Drugs that may be effective in preventing further headaches include topiramate, amitryptiline, valproic acid, and beta-blockers. The chosen drug should be based on any coexisting health conditions and the primary headache disorder.

Chronic Autonomic Cephalgia:

Indomethacin is the preferred medication for several headaches that are triggered by specific activities or occur on just one side of the head. For preventing chronic cluster headaches, verapamil is the preferred drug. However, verapamil needs to be gradually increased to become effective, and other drugs like glucocorticoids or dihydroergotamine can be used for severe episodes. Headaches that don’t respond to medication can be treated with non-invasive techniques that stimulate particular nerves. For chronic SUNCT and SUNA, lamotrigine is the first-choice treatment. Topiramate and gabapentin are alternatives.

What else can Chronic Headaches be?

• Persistent headaches caused by overuse of medication
• Brain tumors
• Long-term infections like brain tuberculosis
• Chronic sinus infection
• Pain related to the neck (Cervical spine-related)
• Brain blood vessels inflammation (CNS vasculitis)
• Problems with the joint that connects your jaw to your skull (Temporomandibular joint issues)
• A condition where the pressure inside your skull increases for no apparent reason (Idiopathic intracranial hypertension)
• Long-standing condition where fluids build up inside the brain (Chronic hydrocephalus)
• Blood-filled sac formed from a weak spot in the wall of a blood vessel in the brain (Cerebral aneurysms)
• Frequent and severe forms of headache on one side of your head (Chronic paroxysmal hemicrania)
• Condition where the lining of an artery, most often in the chest, neck or head, tears away from the wall of the vessel (Artery dissection)
• Brain inflammation (Encephalitis)
• Bleeding within the brain or between the brain and the surrounding membrane (Subarachnoid/intracranial hemorrhage)
• Inflammation of the protective membranes covering the brain and spinal cord (Meningitis)
• Inflammation of the arteries of the skull, also known as temporal arteritis or giant cell arteritis

What to expect with Chronic Headaches

The outcome of chronic headaches can vary greatly. Factors such as anxiety and mood disorders, high stress levels, not enough sleep, ineffective management of headaches, and a lower socio-economic status play significant roles in this outcome. However, patients who have a positive outlook towards their treatment tend to experience less severe and less frequent headaches.

There’s no specific age group that responds better to treatment. But, generally, older individuals tend to experience less severe symptoms. On the same note, people who are employed seem to respond better to treatment compared to those taking a medical leave.

Good exercise habits, regular use of preventive medications, and stopping the overuse of certain medicines are actions that have been found to improve the prognosis of chronic headaches.

Possible Complications When Diagnosed with Chronic Headaches

Patients with certain medical conditions may experience a variety of challenging outcomes. These may include:

• Mood disorders
• Decreased quality of life
• Suicidal thoughts or actions
• Unemployment due to illness
• Progressively worsening neurological symptoms
• Loss of vision
• Seizures
• Frequent tiredness
• Side effects from medications

Preventing Chronic Headaches

People should be taught to better recognize their headache symptoms and triggers. They should also clearly understand any medical actions that are meant to relieve their symptoms.

It’s important for patients to understand the role over-the-counter pain drugs can play in worsening headaches. Patients who suffer from any kinds of regular headaches are at risk of misusing these medicines. They should be advised about the potential risk of regularly using these drugs, as it can actually increase the severity and occurrence of headaches.