Sinus Headaches, Allergies, Asthma, and Migraine: More Than a Casual Relationship?
Roger K. Cady, MD
Facts You Should Know about Sinus Headaches, Allergies, Asthma and Migraine:
Most sinus headache is misdiagnosed and most self-diagnosed and physician diagnosed sinus headache is migraine.
Sinus headache or sinusitis is associated with a pus-like or purulent nasal discharge that represents a potential infection in the sinus(es). Migraine may be associated with watery eyes and runny nose, but the fluid is clear.
People with allergic rhinitis are more than 10 times more likely to have migraine.
Asthma may be associated or comorbid with migraine and a full diagnosis of each is needed.
Identifying potential triggers for asthma is important in reducing the risk of an attack and the risk of triggering a migraine.
In order to survive, all living organisms must be able to separate themselves from their environment. They must be able to absorb nutrients from that environment, while at the same time protect themselves from injury and contamination. To ensure that we live safely within our environment, nature has evolved complex safeguards involving the nervous system, endocrine (hormonal) system, and immune system. As part of this defense system, each portal of entry into the human body has a sophisticated mechanism in place to provide this protection. While most of the time these defense mechanisms function flawlessly, there is the potential for problems; and several important disorders, including migraine, asthma, and allergies, may reflect disruptions of these mechanisms. Disruption of the defense mechanisms designed to protect the lung can result in asthma. If those in the skin or sinus go awry, allergies can result, and if those involving the nervous system are disrupted, migraine can result.
People with migraine inherit a nervous system that is more sensitive to change than those without migraine. This nervous system evolved to be highly vigilant of its environment. When the migrainous nervous system is functioning well, this vigilance is often reflected in positive ways. For example, people with migraine are often well-organized, perceptive, and successful in school and artistic activities. This heightened vigilance may also be why migraine sufferers tend to be light sleepers and more emotionally vulnerable. However, if the nervous system perceives a threat from either the external or internal environment, the nervous system response can be an attack of migraine.
People born with asthma inherit a respiratory or airway system that is more sensitive and vigilant of its environment than those without asthma. When an asthmatic airway is threatened, it can respond dramatically by narrowing too much and creating an inflammatory response in this defense perimeter. This results in wheezing and shortness of breath.
In a similar fashion, people with allergies respond in a variety of ways when their systems are threatened. The most dramatic is an anaphylactic reaction. This is the type of reaction noted rarely with a bee sting or an injection of penicillin and can be fatal. More commonly, allergic individuals develop sinus or skin symptoms that can vary considerably in severity. Seasonal allergies are likely the most common allergic condition. Symptoms generally consist of nasal congestion and discharge, eye irritation, and sometimes headache. Allergies can also be closely associated with asthma.
Observations that link these seemingly diverse disorders together include the fact that they are common in the general population, genetic factors appear to be important for all of them, each can be triggered by internal or external threats, and each represents an over-response or exaggerated response of the very mechanisms that nature designed to protect us. Given these similarities, it is not surprising that if you inherit one of these disorders, you have a greater likelihood of inheriting one or more of the others. When conditions are more likely to occur together than what is found by chance alone in the general population they are called comorbid conditions. In the recent American Migraine Study II, 40%-70% of respondents with migraine had comorbid allergies. Other studies have reported that people with migraine are 2 to 3.5 times more likely to have comorbid asthma, especially if they have a parent with migraine and asthma.
Unraveling the relationships these comorbid disorders have to each other poses many interesting questions. For example, can allergies or asthma trigger migraine? Clearly, these associations appear to be popular beliefs. For example, it has long been assumed that allergies are part of sinus disease and that sinus disease, in turn, results in "sinus headache." In fact, most participants in the American Migraine Study II who had diagnosed migraine also reported having "sinus headaches." However, whether sinus headache and migraine are distinct headache disorders or related to one another is a matter of debate.
Several studies in the medical literature have evaluated a group or population of people who reported they had recurrent attacks of sinus headaches. These patients may be either self diagnosed as having sinus headache or incorrectly diagnosed by a physician as having sinus headache. Either way, many of these people actually have migraine and not sinus headache. The reason there is confusion between sinus headache and migraine is that pain that occurs near or around the sinuses may be incorrectly assumed to be sinus based on this location. However, the truth is that migraine also presents with pain in the forehead and around the eye and therefore may be thought to be sinus. Also these studies tell us that if you have pain that appears to be sinus headache, you should see your doctor and ask for a full diagnosis of your headaches. This is very important because treatment of sinus headache or sinusitis differs significantly from treatment for migraine.
IMPORTANT FACTS ABOUT SINUS HEADACHE AND MIGRAINE
- Most sinus headache is misdiagnosed and these patients may have migraine.
- Sinus headaches are not normally disabling and migraine headaches are.
- True sinus headache or sinusitis is associated with a pus-like or purulent nasal discharge that represents a potential infection in the sinuses. Migraine may be associated with watery eyes and runny nose, but the fluid is clear.
- Sinusitis as a disorder may be associated with headache, but these headaches may differ from migraine.
- Patients with sinusitis may also have migraine.
IMPORTANT FACTS ABOUT ALLERGIC RHINITIS AND MIGRAINE
Allergic rhinitis is a histamine-driven response to an allergen and when exposed to this allergen, the nasal passage becomes inflamed and irritated resulting in a "runny nose". Histamine release has also been suggested to be involved in triggering migraine headaches. Allergic rhinitis can be screened for with simple skin testing at your allergist's office or even in some primary care offices. Many people who have allergic rhinitis also have migraine. People with allergic rhinitis have a general histamine response to something they are allergic to.
- HIstamine release may also be involved in triggering headache, specifically migraine.
- People with allergic rhinitis are more than 10 times more likely to have migraine.
- Accurate diagnoses and treatment of allergic rhinitis will be an important part in reducing the risk of migraine.
- Learning how to treat each condition individually should improve overall care and reduce disability of migraine associated with allergic rhinitis.
IMPORTANT FACTS ABOUT ASTHMA AND MIGRAINE
The relationship between migraine and asthma is equally confusing. Clearly, there is some overlap in the risk or triggering factors for asthma and migraine--for example, stress and certain environmental triggers or allergens. Often migraine sufferers with asthma report that both asthma and migraine can worsen at the same time, and occasionally one seems to lead to the other. In one study, patients with asthma were 1.5 times more likely to also have migraine.
- Asthma may be triggered by a number of different allergens or environmental triggers that also may lead to other airway conditions such as allergic rhinitis.
- Airway conditions including asthma, allergic rhinitis, or sinusitis all may be associated with headache.
- Diagnosing the specific headaches associated with airway conditions is important to ensure that treatment is successful. For example, some over-the-counter allergy medicines may also lead to a worsening of headache in some patients, especially if taken frequently.
- Asthma may be associated or comorbid with migraine and a full diagnosis of each condition is needed.
- Identifying potential triggers for asthma is important for reducing the risk of an attack and the risk of triggering a migraine.
Throughout the literature there are many reports that headaches occur in patients with airway symptoms, including sinusitis, allergic rhinitis or even asthma. The link between these conditions and headache is not well understood, but based on their frequent association, they may be comorbid conditions. To improve the chances of successful treatment, accurate diagnoses for each condition is critical because a single approach is unlikely to be successful in treating both conditions. Additionally, identifying those patients who are incorrectly diagnosed is also important when developing a treatment plan.
Roger K. Cady, MD, Director, Headache Care Center , Springfield, MO Updated November, 2008 from Headache, The Newsletter of ACHE. Summer 2001, Volume 12, Issue 2.