Allergic and Nonallergic Rhinitis Overview

Allergic and Nonallergic Rhinitis

• Incidence of chronic rhinitis has significantly increased in recent decades, particularly in Western countries.
• Moderate to severe rhinitis negatively impacts work and school performance, contributing significantly to healthcare costs.
• Rhinitis is linked to other conditions like asthma, sinusitis, middle ear disease, and dental problems.
• Allergic rhinitis and idiopathic rhinitis are the most common forms, differentiated by immunoglobulin E (IgE) assessment.
• Some cases of rhinitis may arise from localized allergic triggers without systemic IgE involvement.
• Allergy immunotherapy remains the sole treatment that modifies the disease and sustains long-term improvement in nasal symptoms and reduces asthma risk.

Epidemiology

• The International Study of Asthma and Allergies in Childhood (ISAAC) study tracked rhinitis prevalence in a large population.
• Prevalence rates varied substantially across different regions, highest in Western Europe and North America, lowest in Eastern Europe, and south and central parts of Asia.
• The ISAAC study's phase 3 data showed an increase in rhinitis, especially in Western countries.
• Prospective sub-studies found that rhinitis incidence increases with age in children.
• Family history of allergies strongly correlates with higher rhinitis prevalence.
• Data on chronic rhinitis prevalence in adults is more limited.
• Studies of adults indicate that rhinitis prevalence rates vary from 4.6% to 31.8% between 20 and 44 years of age in different regions.

Risk Factors

• Increased Risk: Female gender, particulate air pollution, maternal smoking.
• Decreased Risk: Increased number of siblings, exposure to grass pollen, farm environment, and a Mediterranean diet.

Quality of Life and Economic Impact

• Chronic rhinitis significantly impacts health-related quality of life.
• Patients with chronic rhinitis exhibit decreased physical and social functioning, energy levels, emotional well-being, and pain, especially during frequent outbreaks.
• Poor sleep due to nasal obstruction results in decreased concentration and daytime fatigue.
• Rhinitis can impair productivity at work.

Associated Diseases

• Asthma is found in 40% of patients with chronic rhinitis, and over 80% of asthma patients experience persistent nasal symptoms.
• Nasal inflammation may impact the lower airways of asthma patients.

Diagnosis

• History: Symptoms include nasal congestion, sneezing, rhinorrhea, and pruritus (itching).
• Physical Exam: Examination evaluates the appearance of the nasal passages (mucosal swelling, color, etc.) and identifies abnormalities (such as septal deviation, nasal polyps).
• Laboratory Testing: Testing for allergen-specific IgE is crucial to distinguish allergic rhinitis from non-allergic rhinitis.
• Nasal Cytology: Microscopy of nasal mucus can detect eosinophils (indicating potential allergy)
• Blood Eosinophils and Total Serum IgE: Elevated levels often accompany allergic rhinitis, but their diagnostic value is limited by overlap with non-affected individuals.
• Radiographic Imaging: CT scans are useful for evaluating possible sinusitis.
• Nasal Patency: Tools like acoustic rhinometry are used to objectively assess nasal airflow.

Classification of Rhinitis Syndromes

• Allergic rhinitis: The most common type (estimated 50% of cases), triggered by airborne allergens.
• Other Forms: Other forms include NARES, cold-air induced rhinitis, and exercise-induced rhinitis. Types also include work-related and atrophic rhinitis

Treatment

• Allergen Avoidance Measures: Avoidance of specific allergens (e.g., dust mites, pet dander, molds) is typically a first treatment.
• Pharmacotherapy:
  • Antihistamines: Block histamine and improve symptoms such as sneezing, itching, and runny nose, but less effective for nasal congestion.
  • Decongestants: Reduce nasal congestion through vasoconstriction (topical is more common, with lower side effects), but rebound congestion can occur with prolonged use.
  • Intranasal Corticosteroids (INS): Powerful anti-inflammatory agents. Effective in reducing nasal symptoms in both allergic and nonallergic rhinitis.
  • Leukotriene Inhibitors: These agents target leukotrienes, another inflammatory mediator (usually not first-line).
  • Anticholinergics: Effective for rhinorrhea when other measures are insufficient.
• Systemic Corticosteroids: Reserved for severe cases due to potential side-effects, helping to improve access to intranasal corticosteroids.
• Cromolyn Sodium: Useful for allergic rhinitis, helpful for reducing sneezing, itching and discharge, but less effective for congestion.
• Other Treatments: Combinations of medications, especially antihistamines plus intranasal corticosteroids (INS) may be more beneficial. Allergy immunotherapy might also be used.

Local allergic rhinitis

• A form of rhinitis showing signs of allergy to specific allergens, but without detectable systemic allergies.

Nonallergic Rhinitis

• Often idiopathic, not associated with an allergic response, symptoms include nasal congestion, rhinorrhea, and pruritus.
• Associated factors can range from irritant exposure to hormonal changes or medications.

Treatment for Special Populations

• Pregnancy: Nondrug treatments (nasal rinsing and mechanical dilators) are prioritized, with consideration of medications like cromolyn or intranasal corticosteroids if needed.
• Elderly: Nasal irrigation, and careful consideration of INS, as it might lead to more bleeding. Avoiding oral antihistamines that might cause sedation/anticholinergic effects, along with other medications suspected to be triggers.
• Competitive Athletes: Be aware of drug restrictions by sports governing bodies.

Overall Treatment

• The approach emphasized a stepped care model, starting with non-drug measures then progressing to pharmacotherapy or immunotherapy depending on severity.

Summary of Rhinitis

• Chronic rhinitis is a growing concern, significantly impacting quality of life and associated with healthcare costs.
• Identification of the causes and treatment of rhinitis are important for patient well-being, especially in patients with complications like asthma.