Allergic rhinitis: An update on therapy
Allergic rhinitis (AR) is the fifth-most common chronic disease in the United States and the third-most common reason that patients aged 25-44 visit a clinician.1 Only routine health maintenance and pregnancy are more common reasons for clinician visits among patients in this age group. With those numbers you'd think AR would command respect and attention. But AR is an often overlooked and underappreciated diagnosis.
Evaluating the patient with AR
A diagnosis of AR is typically confirmed after documentation of the patient's symptoms and a few physical and diagnostic tests. Typically, patients are questioned about the pattern, chronicity, and seasonality of symptoms; what medications they have tried; and which ones have been helpful.
On careful questioning, it should be possible to classify the patient's AR as (1) intermittent or persistent and (2) mild or moderate/severe, according to the criteria set forth by the world health initiative Allergic Rhinitis and its Impact on Asthma (ARIA). This classification system is an alternative to the traditional seasonal, perennial, and occupational AR classification scheme.
The contemporary ARIA system classifies symptoms as intermittent (occurring fewer than four days a week or for fewer than four weeks per year) or persistent. Symptoms are further classified as mild (with no impairment in activities or function and no troublesome symptoms) or moderate/severe.2
Anterior rhinoscopy with a speculum and mirror is the minimum nasal examination that should be conducted on a patient with suspected AR. The ARIA guidelines stipulate that nasal endoscopy conducted by a specialist is preferable to anterior rhinoscopy.2 Specific immunoglobulin (Ig) E-mediated allergic reactions are confirmed by immediate hypersensitivity skin tests. Appropriate interpretation requires administration by a qualified specialist.
Objective measures of AR severity are not currently in clinical use. In brief, patients can be classified as “sneezers and runners” or “blockers.” It can be easy to overlook a diagnosis of AR in a patient whose primary symptom is nasal stuffiness or blockage, however. Clues include frequent sore throats, a sensation of dryness in the mouth or throat, snoring, and a nasal quality in the voice. In contrast, patients in whom rhinorrhea and sneezing are predominant may have the familiar transverse crease across the lower third of the nose, the result of frequently pushing up against the tip of the nose to alleviate itching and sneezing.3
The management of AR has three components: allergen avoidance, pharmacologic therapy, and immunotherapy.2 These components are not equally important in all patients. Each one deserves some consideration, however, as part of AR case management.
Agents that unleash immunoglobulin (Ig)E-dependent AR symptoms include dust mites, pollen, mold, animals, and insect allergens.3 Some allergens are more easily avoided than others. Pollens and molds are ubiquitous and perhaps the most difficult to avoid. A pet that is linked to a patient's allergy can be removed from the home with the expectation that symptoms will improve, but families are often unwilling to take this step.
Keeping windows closed and air-conditioning on during peak pollen seasons will decrease exposure. Mold exposure is particularly high in barns, on hay rides, and when raking leaves or mowing the lawn.
While many studies have assessed the role of allergen avoidance in patients with asthma, far fewer have examined its benefits in patients with AR. There is an abundance of evidence that a total environmental-control program will benefit patients with house-dust-mite sensitivity. This includes keeping relative humidity at ≤50%, making the bedroom as plain and uncluttered as possible, using anti-allergic covers for pillow and mattress, washing the bedding at 130°C, and removing the rug, if feasible.4
The ARIA guidelines suggest that more data be collected on the usefulness of allergen reduction in the management of AR. Until then, patients (or parents) should be advised to use air conditioning, avoid situations known to provoke symptoms, dust frequently, use a vacuum with a double filtration system, and bathe pets frequently (if they cannot be removed from the home).3