Chronic Allergic Rhinitis Causes and Risk Factors

Primary Causes

The American Academy of Otolaryngology-Head and Neck Surgery states that chronic allergic rhinitis is primarily caused by an IgE-mediated inflammatory response of the nasal mucous membranes after exposure to inhaled allergens, which can be classified as perennial, seasonal, or episodic depending on the pattern of allergen exposure 1, 2
Dust mites are a major cause of year-round symptoms in many climates, according to the Journal of Allergy and Clinical Immunology 3, 4
Animal dander, particularly from household pets like cats and dogs, is a common allergen 4, 5
Indoor mold can persist throughout the year in damp environments and is a known allergen 4, 2
Tree pollens are typically prevalent in spring and are a common seasonal allergen 1, 6
Grass pollens are most common in late spring and summer, causing seasonal allergic rhinitis 4
Weed pollens, especially ragweed, are predominant in fall and can cause seasonal allergic rhinitis 4
Outdoor molds have levels that fluctuate seasonally, with higher concentrations in warm, humid weather, and can cause seasonal allergic rhinitis 4, 2

A family history of atopy significantly increases the risk of developing chronic allergic rhinitis, especially when both parents have atopic conditions 7
Elevated serum IgE levels in early childhood, greater than 100 IU/mL before age 6, are associated with an increased risk of developing chronic allergic rhinitis 7
Early and repeated exposure to specific allergens can lead to sensitization and increase the risk of developing chronic allergic rhinitis 7
Higher socioeconomic status is associated with an increased risk of developing chronic allergic rhinitis 7
Heavy tobacco smoke exposure in early childhood increases the risk of developing chronic allergic rhinitis 7
Urban living with increased pollution exposure is associated with an increased risk of developing chronic allergic rhinitis 7

The allergic response in chronic allergic rhinitis involves the release of inflammatory mediators, including histamine, leukotrienes, and cytokines, after re-exposure to allergens 4, 8
The early-phase response is characterized by sneezing, itching, and rhinorrhea, while the late-phase response is dominated by nasal congestion due to inflammatory cell recruitment 4, 8

Persistent symptoms of chronic allergic rhinitis, lasting more than 4 days a week and more than 4 weeks a year, can significantly impact quality of life, sleep, work productivity, and school performance, according to the American Academy of Otolaryngology-Head and Neck Surgery 2
Chronic allergic rhinitis is associated with comorbidities, including asthma and sinusitis, which can have a significant impact on quality of life 4

The American Academy of Otolaryngology-Head and Neck Surgery classifies allergic rhinitis as intermittent or persistent, with symptoms occurring <4 days per week or <4 weeks per year for intermittent, and >4 days per week and >4 weeks per year for persistent 9, 10

The economic burden of allergic rhinitis is significant, generating $2-5 billion in direct health expenditures annually in the United States, according to the American Academy of Otolaryngology-Head and Neck Surgery 9