Headaches are a common medical complaint, and understanding the difference between primary and secondary headaches is essential for proper diagnosis and treatment.
In this article, we will discuss the characteristics of primary and secondary headaches, their underlying causes, and how to approach the diagnosis and treatment of various headache syndromes.
Primary vs secondary headaches
Primary headaches are those in which the headache does not originate from any underlying pathology. There is no known cause for the headache, and the focus is usually on treatment. Examples of primary headache syndromes include migraines, tension-type headaches, and cluster headaches.
Secondary headaches, on the other hand, have an identifiable cause, and the main goal is to determine that cause and treat it, either medically or surgically.
Some examples of secondary headaches include brain tumors, subarachnoid hemorrhage and glaucoma. Secondary headaches are less common than primary headaches, but they can be life-threatening, so prompt evaluation and treatment is crucial.
| primary headache | secondary headache |
|---|---|
| Caused by an underlying or primary disorder | Result of another medical condition or medication |
| Often presents as a tension-type headache | Often presents as a migraine |
| May have a gradual start | Often has sudden onset |
| Pain is usually mild to moderate | Pain can vary from mild to severe. |
| Often relieved by over-the-counter pain relievers | May require prescription drugs to relieve symptoms |
Assessment of Headache Syndromes
When evaluating a patient with a headache, it is essential to begin by asking questions to identify possible secondary causes. These may include thunderclap or sudden-onset headaches, headaches accompanied by visual disturbances, neuralgiform headaches, and headaches associated with high or low blood pressure.
Differentiation between primary and secondary headaches can often be achieved through a thorough clinical examination. In primary headaches, the focus is typically on treatment, whereas in secondary headaches, diagnosis comes first, followed by treatment.
Types of headaches and their clinical features
Migraine
These are typically one-sided headaches characterized by pulsating, throbbing pain that can be exacerbated by bright lights, loud noises, or strong smells.
Migraines are usually accompanied by photophobia, phonophobia and osmophobia, as well as nausea and vomiting. Some patients experience aura, which may include visual disturbances such as scotomata or shimmering scotomata, prior to headache onset.
Migraines can be classified into several subtypes:
- episodic migraine: Occurs when an individual experiences less than 15 headache days per month.
- Chronic Migraine: Occurs when an individual experiences more than 15 headache days per month.
- Migraine with Aura: Characterized by neurological symptoms that precede the onset of the headache, such as visual disturbances or numbness.
- migraine without aura: Migraine without preceding neurological symptoms.
Migraines typically do not exhibit prominent autonomic features such as watery eyes or nasal congestion. These headaches can be triggered by stress and may respond to triptans, which are abortive migraine treatments.
Frequency, duration, location and severity can vary between individuals and even between different migraine episodes for the same person. Some common features include:
- Duration: Migraines can last from 4 to 72 hours.
- Location: the pain can be unilateral, on both sides or change between sides.
- Gravity: Moderate to severe pain, often described as throbbing or pulsating.
| Phase | Description | pathophysiology |
|---|---|---|
| Pródromo | Aura or warning symptoms that may appear days or hours before the migraine. | An increase in the release of glutamate, a neurotransmitter, from nerve endings. |
| Aura | Sensory disturbances that usually occur shortly before the onset of a migraine. | An increase in the activity of the trigeminovascular pathway, which is a network of nerves that extends from the brain to the face and scalp. |
| Attack | The migraine headache phase that usually lasts for several hours. | The release of inflammatory mediators, such as prostaglandins and substance P, in the trigeminal nerve endings in the brain. |
| Postodrome | The period after the migraine attack when the patient may experience fatigue and cognitive difficulties. | The activity of inflammatory mediators, such as cytokines, which can cause fatigue and cognitive difficulties. |
Migraine sufferers may experience a variety of symptoms, including:
- nausea and vomiting
- Photophobia (sensitivity to light)
- Phonophobia (sensitivity to sound)
- Osfresiophobia (sensitivity to smell)
- Headache worsens with physical activity
- Aura symptoms (visual disturbances, numbness, speech difficulties)
- Prodrome symptoms (irritability, depression, yawning, sensitivity to light and sound)
- Postdromic symptoms (difficulty concentrating, fatigue, depressed mood)
Tension-type headache
These headaches are different from migraines in that they usually lack photophobia, phonophobia, nausea, vomiting, and aura. Tension-type headaches are often described as a bilateral band-like pressure around the head.
They typically do not have prominent autonomic features such as watery eyes or nasal congestion.
Tension-type headaches were initially thought to be due to sustained or prolonged contractions in the muscles of the neck, head and face. However, current research suggests that sensitization of pain receptors, or nociceptors, in the connective tissues of the head is the primary cause.
Stress and mental tension are commonly reported as precipitating factors for tension-type headaches. Treatment options include relaxation techniques, over-the-counter pain relievers such as acetaminophen and ibuprofen, and combination medications such as Excedrin.
Characteristics of tension-type headaches
- Duration: It can last from 30 minutes to a week.
- Location: Typically felt on both sides of the head, with a feeling of tightness or compression.
- Gravity: Mild to moderate pain, usually not disabling.
cluster headache
They are not migraine variants and generally do not exhibit migraine-specific features such as photophobia, phonophobia, nausea, vomiting, and aura.
Cluster headaches are paroxysmal headaches characterized by severe, one-sided pain located behind the eye. They are accompanied by prominent autonomic features such as tearing, nasal congestion, and conjunctival congestion on the same side as the headache.
They are characterized by their frequency, duration and location:
- Frequency: Cluster headaches usually occur daily or several times a day for several weeks to months, followed by a period of remission that can last for several months or even years.
- Duration: Each cluster headache episode can last from 15 to 180 minutes.
- Location: Pain is usually one-sided, often felt behind one eye and does not change sides.
Cluster headache sufferers may experience a variety of symptoms, including:
- Red eye or droopy eyelid
- tearing of the eye
- small pupil
- Runny or stuffy nose
- Sweating or swelling of the face
- Sensation of fullness in the ear
Cluster headaches may respond to both triptans and oxygen therapy, but not to indomethacin.
Hemicrania Continua
Hemicrania continua is a very rare type of headache that affects women more than men.
This headache is similar to cluster headaches in that it is unilateral and may have some migraine-like features such as photophobia, phonophobia, nausea and vomiting, although these are not as prominent as in migraines.
Like an autonomic headache, hemicrania continua presents with watery eyes and nasal congestion. The main distinguishing feature is its responsiveness to indomethacin, which serves as a diagnostic and therapeutic intervention for these patients.
It is characterized by its frequency, duration and location:
- Frequency and duration: The pain is constant, occurring 24 hours a day, 7 days a week.
- Location: The headache is strictly one-sided and does not change sides.
Similar to cluster headaches, individuals with hemicrania continua may experience symptoms on the same side as the headache, such as:
- Red eye or droopy eyelid
- tearing of the eye
- small pupil
- Runny or stuffy nose
- Sweating or swelling of the face
- Sensation of fullness in the ear
primary acute headache
This headache is characterized by brief, sharp, sharp pain, like a knife being driven into the brain. It presents with brief, clustered episodes of stabbing pain and responds to indomethacin, an important diagnostic and therapeutic intervention.
exertional headache
As the name suggests, this type of headache is induced by exertion or stress. May respond to indomethacin but should not be confused with hemicrania continua or primary stabbing headache.
Exertional headaches can present with varying degrees of nausea, vomiting, and photophobia, which many people may experience during intense physical activity.
Medication overuse headache
Analgesic abuse headache, also known as rebound headache, is a type of headache that occurs due to overuse of pain-relieving medications. May contribute to the transformation of episodic migraines into chronic migraines.
To avoid this headache, limit the use of rescue medications to no more than ten days a month.
Conclusion
Understanding the difference between primary and secondary headache disorders is crucial for healthcare professionals when diagnosing and treating patients with headaches.
By asking the right questions, conducting thorough clinical examinations, and considering the various headache types and their unique clinical features, healthcare professionals can effectively diagnose and manage headache disorders to improve patient outcomes.
Source: blogdasaude.com.br
