Allergic Rhinitis Causes and Risk Factors

Definition and Prevalence

Allergic rhinitis is an IgE-mediated inflammatory response of the nasal mucous membranes after exposure to inhaled allergens, characterized by rhinorrhea, nasal congestion, nasal itching, and sneezing, affecting approximately 1 in 6 Americans and generating $2-5 billion in direct health expenditures annually, according to the American Academy of Otolaryngology-Head and Neck Surgery 1.

Occupational rhinitis may be triggered by allergic factors or irritant factors such as chemicals, grain dust, and ozone, as stated by the Journal of Allergy and Clinical Immunology 2, 3.
Chemical exposures can cause two distinct types of rhinitis: IgE-mediated allergic occupational rhinitis and irritant-induced rhinitis, as noted by the Journal of Allergy and Clinical Immunology and Chest 4, 5.
The American Academy of Allergy, Asthma, and Immunology recommends considering temporal relationship between exposure and symptoms when evaluating potential occupational or environmental causes of rhinitis, and assessing for characteristic allergic symptoms versus primarily congestive symptoms with irritant exposure 2, 3, 5.

Established risk factors for allergic rhinitis include genetic predisposition and family history of atopy, elevated serum IgE levels in early childhood, higher socioeconomic class, and positive allergy skin prick test, as reported by the American College of Allergy, Asthma, and Immunology 6.
Environmental risk factors include exposure to indoor allergens, outdoor allergens, and occupational allergens, according to the American Academy of Allergy, Asthma, and Immunology 6.

When evaluating potential occupational or environmental causes of rhinitis, it is essential to distinguish between allergic rhinitis and irritant-induced rhinitis, and consider the strength of evidence, which is currently limited for chemical exposures causing true allergic rhinitis, as stated by the Journal of Allergy and Clinical Immunology 2, 5, 7.