What is the introduction, epidemiology, and global and Indian burden of Allergic Conjunctivitis (AC), also known as Allergic Rhinoconjunctivitis?

From the Guidelines

Allergic conjunctivitis is a significant global health issue, affecting approximately 20-40% of the population worldwide, with a substantial burden in India, where it affects around 15-20% of the population, particularly in urban areas. The condition is characterized by ocular itching, redness, tearing, and sometimes swelling of the eyelids, triggered by an allergic response to environmental allergens. According to the most recent study 1, conjunctivitis is very common worldwide, with a broad spectrum of disease severity and underlying etiologies. The prevalence of allergic conjunctivitis varies significantly by region, influenced by environmental factors, genetic predisposition, and lifestyle. In developed countries, the prevalence has been increasing over recent decades, likely due to changes in environmental exposures and living conditions.

Some key points to consider:

• The disease burden is substantial, with seasonal variations noted particularly during spring and monsoon seasons when pollen and mold counts are elevated 1.
• The economic impact is significant, including direct healthcare costs for medications and consultations, as well as indirect costs from decreased productivity and quality of life 1.
• Children and young adults are disproportionately affected, with allergic conjunctivitis often occurring alongside other atopic conditions such as asthma, allergic rhinitis, and eczema.
• The condition, while rarely sight-threatening, significantly impacts quality of life through chronic discomfort, sleep disturbance, and interference with daily activities including school and work performance.
• Treatment options that address ocular symptoms may have a large beneficial impact on quality of life and decrease direct and indirect costs associated with allergic rhinitis 1.

The impact of allergic conjunctivitis on quality of life is significant, with studies showing that the presence of ocular symptoms reduces quality of life, reduces work productivity, and increases resource utilization regardless of the severity of nasal symptoms 1. In India, the urban predominance of allergic conjunctivitis is attributed to increased exposure to air pollution, dust mites, and other urban allergens. Overall, the management of allergic conjunctivitis requires a comprehensive approach, taking into account the individual's specific needs and circumstances, to minimize the impact on quality of life and reduce the economic burden.

From the Research

Introduction to Allergic Conjunctivitis

• Allergic conjunctivitis is an allergen-induced immune response secondary to the binding of immunoglobulin-E (IgE) to sensitized mast cells 2.
• It is a disease of increasing prevalence that affects both children and adults and causes significant deterioration of their quality of life and sometimes irreversible visual damage 3.

Epidemiology and Burden

• Approximately 40% of North Americans and 20% of the world's population are impacted by some form of allergy, and it continues to increase in prevalence, especially among children 2.
• Allergic conjunctivitis represents one of the most frequent ocular surface diseases affecting more than 30% of the young-adult population and shows an increasing incidence over the years 4.
• In the U.S., up to 40% of the population is deemed to be affected, and this number is growing 5.

Global and Indian Burden

• There is no specific data available in the provided studies regarding the burden of allergic conjunctivitis in India.
• However, it is mentioned that approximately 20% of the world's population is impacted by some form of allergy, which includes allergic conjunctivitis 2.

Types and Symptoms

• There are various forms of allergic conjunctivitis, including seasonal and perennial allergic conjunctivitis, giant papillary conjunctivitis, and contact allergic blepharoconjunctivitis 3.
• Symptoms and signs of ocular allergies include itching, tearing, chemosis, and hyperemia, which can lead to decreased productivity and poor quality of life 2, 5.
• Ocular itching, swelling, and tearing are the most frequent symptoms complained by patients with all forms of allergic conjunctivitis, while photophobia and pain are typical of the most severe forms 4.

Treatment Options

• Many treatment options are available to improve symptoms, including mast cell stabilizers, antihistamines, dual-acting agents, steroids, nonsteroidal anti-inflammatory drugs (NSAIDs), and other off-label treatment modalities 2, 5.
• Topical antihistamines and mast cell stabilisers are effective in reducing symptoms and signs of seasonal allergic conjunctivitis when compared with placebo 6.
• Immunotherapy is recommended as a therapeutic option for allergic conjunctivitis 5.