Allergic Rhinitis (AR) is rising in incidence in both developed and developing countries. Genetics and epigenetics have a potential role to play. The pattern and severity of AR have implications with regard to choice of treatment, which itself could be related to patient specific genetic and epigenetic factors. Hence, the present study was undertaken to correlate the patient characteristics with AR pattern and severity, in order to understand the pathophysiology of AR. The study also aimed to find out the allergen sensitivity pattern among patients attending a tertiary care centre of rural central India, where climatic variations make it a high prevalence zone. Prospective Observational study on 90 patients with clinically diagnosed Allergic Rhinitis confirmed by Skin Prick Tests. Patient characteristics like demographic data, data relevant to allergen exposure, occupation, family history of atopy and gender; and Disease characteristics like severity (mild, mod-severe), pattern (continuous/ intermittent), type of disease (seasonal/perennial) were noted, analysed and correlation studied. Majority of the patients with AR were in the age group of 15-40 years. Medical students (52%) suffered from moderate to severe type of Allergic Rhinitis, with Persistent disease in approximately 80%. Similarly, 70.59% of farmers had moderate to severe type of the disease, with persistent disease in 70%. In the present study, in clinically diagnosed allergic rhinitis patients, Mite was the commonest allergen found on Skin Prick Test overall and in Medical students, whereas Pollen sensitivity was more common among farmers. 56.66% of the patients had negative family history of atopy. Severity and type of AR depend on allergen exposure. In farmers and medical professionals, persistent and moderate to severe type of disease was more common, as they were persistently exposed to different type of allergens, mites in case of medical professionals and pollens in farmers. Hence, the Disease characteristics, as defined by ARIA guidelines, should not be taken in isolation and management should consider the Patient characteristics for deciding and devising protocols. In the present study, more than 50% patients were without family history of atopy. Hence, the role of various environmental factors, leading to epigenetic changes could be a major contributor in the increase in incidence of allergic rhinitis in recent times. Occurrence of perennial moderate to severe form of disease, in majority of farmers, defies the phenomenon of "Hygiene Hypothesis", focusing on the role of epigenetic changes and various outdoor allergens in the development of allergic rhinitis in them.
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