What Are The Common Types of Rhinitis
Rhinitis is one of the most common chronic conditions for which medical care is sought. Studies in the United States and United Kingdom have estimated the prevalence of allergic rhinitis to be between 24-28%. In the U.S., the management of rhinitis accounts for nearly 3 percent of all physician visits with a direct cost estimated at 4.5 billion dollars annually. Though rhinitis alone is never life threatening, its impact on quality of life and both work and school productivity is significant. Furthermore, rhinitis can worsen other chronic conditions such as sinusitis, otitis and asthma, all of which have significant morbidity.
The nose and nasal cavities have a number of important functions. Airflow into the nasal passages is necessary for both the senses of smell and taste. The nasal passages also act as a filter protecting the lungs from particulate matter. Furthermore, the relatively large surface area of the mucosa covered turbinates act to warm and humidify air prior to entry into the lungs. When airflow is significantly inhibited, all of these functions can be adversely affected. In rhinitis, a combination of nasal mucosal inflammation and increased mucus production can lead to such airflow obstruction.
The two common types of rhinitis are :
- Allergic Rhinitis
- Non-allergic Rhinitis
The condition for allergic rhinitis can either be seasonal or year-round. These two conditions are :
- Seasonal allergic rhinitis is also known as hay fever.
- Perennial allergic rhinitis which appears all year-round.
The condition for non-allergic rhinitis can appear all year-round. It is known as perennial non-allergic rhinitis.
Though rhinitis is commonly thought of as a response to the deposition of allergens on the nasal mucosa, a significant percentage of patients suffering with rhinitis are not allergic. So-called non-allergic rhinitis is not one uniform syndrome but instead a collection of disorders that lead to the classic symptoms of rhinitis including rhinorrhea and/or nasal congestion. The types of non-allergic rhinitis are varied and include vasomotor, hormonal, drug-induced, irritant-induced and many others. Non-allergic rhinitis may effect as many as 30-50% of rhinitic patients and is especially common in patients with adult-onset nasal symptoms.
Allergic rhinitis typically presents at a younger age and symptoms are usually evident by young adulthood. Symptoms can be purely seasonal or year round (persistent) depending on the sensitizing allergen or allergens. Classically, the symptoms of allergic rhinitis include congestion and/or rhinorrhea accompanied by nasal itch and sneezing. Allergic rhinitis is frequently accompanied by allergic conjunctivitis with symptoms of conjunctival injection, itch, and excessive tearing and crusting. These patients are also more likely to have asthma and atopic eczema, the other diseases of the atopic diathesis.
The effect of rhinitis on quality of life is not minimal. Standardized quality of life measures have found that 62% of patients with allergic rhinitis are bothered a great deal while symptomatic. Studies have also shown that almost 80% of patients with allergic rhinitis report difficulty sleeping and thus increased daytime fatigue. In the U.S., allergic rhinitis contributes to approximately 2 million missed school days and 100 million missed work days annually. Furthermore, both adults and school-aged children with rhinitis have been found to have decreased levels of cognitive functioning.
Both allergic and non-allergic rhinitis can be associated with secondary complications and co-morbidities. The nasal inflammation caused by rhinitis can contribute to the development of both acute and chronic sinusitis. Sinusitis is the third leading disease for which antibiotics are prescribed in the outpatient setting. Rhinosinusitis has also been shown to contribute to asthma exacerbations and make asthma more difficult to control. Rhinitic mucosal inflammation can also lead to eustachian tube dysfunction and chronic otitis media and/or serous otitis. These disorders in turn can lead to speech delay in pediatric populations and in rare cases permanent hearing damage. Also in children, rhinitis can contribute to craniofacial abnormalities and chronic mouth breathing