Therapeutic considerations

Treatment modalities recommended for patients with AR. According to the ARIA guidelines, the management strategies include four components: 

1) Patient education; 

2) Prevention of exposure to environmental allergens and irritants; 3) Pharmacological therapies; and 

4) Immunotherapy.

The effective first line drugs for AR are non-sedating antihistamines and intranasal corticosteroids. Other drugs with favorable efficacy and safety profiles include leukotriene receptor antagonists, chromones, and topical and oral decongestants. Subcutaneous immunotherapy and sublingual immunotherapy are effective and have preventative as well as long lasting effects on the disease.

In developing countries, there are limitations for the adequate treatment of AR, such as little access to specialized diagnosis and treatment, the small number of allergists, lack of confirmatory in vivo and in vitro diagnostic tests, and the cost of medications or immunotherapy

Co-morbidities, and especially asthma, must be treated concomitantly with AR. The ARIA guidelines strongly recommend that patients with AR be evaluated for asthma, and that patients with asthma be assessed for AR.

Unmet Needs 

• To define control of AR. 

• To define severe AR. 

• To define phenotypes and disease heterogeneity. 

• Additional therapies for unresponsive patients. 

• Pharmaco-economic studies. 

• Increased access to diagnosis and treatment, including allergen-specific immunotherapy, in developing countries.

Allergic Conjunctivitis

Key Statements 

• Allergic conjunctivitis is an increasingly prevalent allergic disease, with the same clinical gravity as allergic asthma and allergic rhinitis. 

• The umbrella term “allergic conjunctivitis” includes distinct clinical entities, from mild but disturbing forms due to IgE sensitization to aeroallergens, to forms of keratoconjunctivitis where the severe allergic inflammation, with corneal involvement, is more difficult to diagnose and treat, and may lead to permanent ocular damage and even loss of vision.

Introduction 

Allergic conjunctivitis is the most common cause of a red eye, affecting more than one billion people globally. There are several clinical forms of allergic conjunctivitis; intermittent or seasonal (SAC), persistent or perennial (PAC), vernal (VKC), atopic (AKC) and induced by contact lenses (CLC).  

The burden of allergic diseases

Allergic Rhinitis

Key statements 

• Allergic rhinitis (AR) results from an IgE-mediated inflammation of the nasal mucosa. 

• The disease currently affects between 10% and 30 % of the population. 

• Studies indicate that prevalence rates are increasing worldwide. 

• The classification proposed in the Allergic Rhinitis and its Impact on Asthma (ARIA) guidelines is useful for the implementation of treatment. 

• AR is a risk factor for asthma. 

• Other co-morbidities of AR include: sinusitis, nasal polyposis, conjunctivitis, otitis media with effusion, upper respiratory infections, breathing through the mouth, and sleep disorders. 

• AR has a significant impact on patients based on the degree of the severity of their symptoms. It has psychological effects, interferes with social interactions, and creates an economic burden not only for the affected subject, but for the family and for the society at large. 

• Management is based on patient education, environmental control measures, pharmacotherapy and specific immunotherapy

Introduction

Allergic rhinitis is defined by the presence of nasal congestion, anterior and posterior rhinorrhea, sneezing, and nasal itching secondary to IgE-mediated inflammation of the nasal mucosa. It must be differentiated from other non allergic forms of rhinitis with a similar clinical picture

Risk factors for the development of AR include a family history of atopic diseases, increased total serum IgE before 6 years of age, higher socio-economic class, and the presence of positive immediate-type hypersensitivity skin tests. The most common causative allergens include pollens, dust mites, molds, and insects.

Atopic subjects inherit a predisposition to produce specific IgE antibodies that bind to high-affinity receptors on mast cells. In the nose, IgE-bound mast cells recognize the allergen and degranulate, releasing preformed mediators (histamine, tryptase, chymase, kininogenase, heparin, and other enzymes). Newly formed mediators including prostaglandin D2 and cysteinyl leukotrienes are released by mast cells, eosinophils, basophils, and macrophages and produce edema, rhinorrhea, mucosal hypertrophy, mucus secretion, and vasodilation leading to nasal obstruction. Stimulation of sensory nerves results in nasal itch, sneezing, and increased congestion. This early allergic response is followed by a late-phase response starting 4 - 8 hours after allergen exposure, which is characterized by congestion, postnasal mucous discharge, hyposmia, and nasal hyperreactivity to non specific environmental stimuli. Repeated mucosal exposure to allergens results in a priming mechanism by which the amount of allergen required to induce an immediate response decreases as a consequence of the influx of inflammatory cells

Prevalence

Allergic rhinitis is the most common form of non-infectious rhinitis, affecting between 10% and 30% of all adults and as many as 40% of children. Epidemiologic studies show that the prevalence of AR continues to increase worldwide. The World Health Organization has estimated that 400 million people in the world suffer from AR, and 300 million from asthma.

In the United States of America, the prevalence of AR ranges from 3% to 19%. According to the Centers for Disease Control and Prevention, 23.7 million cases were reported in 1996. Overall, it affects 30 to 60 million individuals annually. In childhood, affected boys outnumber girls, but the sex ratio is about equal in adults. AR develops before the age of 20 years in 80% of cases. Increased prevalence is observed in non whites, in some polluted urban areas, and in first-born children. AR accounts for 16.7 million physician office visits annually.

In Europe, the European Community Respiratory Health Survey established the prevalence of AR as being from 4% to 32%. The International Study on Asthma and Allergies in Childhood (ISAAC) reported the prevalence of allergic rhinitis in Latin America.

THE BURDEN OF ALLERGIC DISEASE

Allergic Rhinitis 

• Allergic rhinitis (AR) results from an IgE-mediated inflammation of the nasal mucosa. 

• The disease currently affects between 10% and 30 % of the population. 

• Studies indicate that prevalence rates are increasing worldwide. 

• The classification proposed in the Allergic Rhinitis and its Impact on Asthma (ARIA) guidelines is useful for the implementation of treatment. 

• AR is a risk factor for asthma. 

• Other co-morbidities of AR include: sinusitis, nasal polyposis, conjunctivitis, otitis media with effusion, upper respiratory infections, breathing through the mouth, and sleep disorders.

• AR has a significant impact on patients based on the degree of the severity of their symptoms. It has psychological effects, interferes with social interactions, and creates an economic burden not only for the affected subject, but for the family and for the society at large. 

• Management is based on patient education, environmental control measures, pharmacotherapy and specific immunotherapy.

Allergic Conjunctivitis 

• Allergic conjunctivitis is an increasingly prevalent allergic disease, with the same clinical gravity as allergic asthma and allergic rhinitis.

• The umbrella term “allergic conjunctivitis” includes distinct clinical entities, from mild but disturbing forms due to IgE sensitization to aeroallergens; to forms of keratoconjunctivitis where the severe allergic inflammation, with corneal involvement, is more difficult to diagnose and treat, and may lead to permanent ocular damage and even loss of vision.

Rhinosinusitis 

• Rhinosinusitis (RS) is one of the most common and expensive medical conditions. 

• RS occurs in a number of forms, the most common of which are either acute or chronic. 

• Initial treatment of RS is usually by a primary care physician (PCP) and if unsuccessful, the PCP should refer either to a surgeon or to an allergist for specialized care. 

• In the vast majority of cases, RS is controlled by proper medical management without the need for surgery. 

• Surgery should only be considered in those patients who are properly managed but in whom a number of medical treatment programs fail. 

• The Allergist, who is trained in allergy, immunology, microbiology, internal medicine and/or pediatrics combined with an expert knowledge of nasal and sinus anatomy and appropriate pharmacology, is best suited to manage RS.

Asthma 

• Asthma is a life-long chronic inflammatory disorder of the airways, associated with variable structural changes, that affects children and adults of all ages. It is associated with airway hyperresponsiveness and airflow obstruction that is often reversible either spontaneously or with treatment. 

• When uncontrolled, asthma can cause death, and can markedly interfere with normal activities, seriously impacting an individual’s quality of life.

• Because of under-diagnosis and inadequate treatment, asthma presents a serious public health problem throughout the world; especially in low and middle income countries.

• Atopy - the genetic predisposition to develop IgEmediated sensitivity to common aeroallergens, is the strongest identifiable predisposing factor to the development of asthma, especially in children.

• There was a sharp increase in the prevalence, morbidity, and mortality associated with asthma beginning in the 1960s and 1970s in the so-called “Westernized” countries of the world. 

• The prevalence of asthma in different countries varies widely, but the disparity is narrowing due to rising prevalence in low and middle income countries as they adopt a more Western-type lifestyle. It is plateauing in high income countries. 

• Inhaled corticosteroids are currently the most effective antiinflammatory medications to treat persistent asthma. 

• The monetary costs of asthma are substantial and include both direct medical costs and the indirect costs, the latter associated with time lost from work and premature deaths. 

• National efforts to tackle asthma as a public health problem, such as the program introduced in Finland, produce remarkable benefits that are reflected in dramatic reductions in deaths and hospital admissions.

• Many barriers exist to a reduction in the worldwide burden of asthma. 

• There are unmet diagnostic, therapeutic, educational and financial needs to achieve better worldwide control of asthma.

 • More effort is needed to focus on ways to improve the management of asthma by focusing on disease control rather than treating acute episodes. This concept has to be embedded in healthcare programs.