Padukudru Anand Mahesh, Attahalli Shivanarayanprasad Praveena, Mohammed Kaleem Ullah, Mandya Venkateshmurthy Greeshma, Jayaraj Biligere Siddaiah, Jefferson Daniel, Devasahayam Jesudas Christopher, Krishnarajah Nirantharakumar, Adel H. Mansur, Glenis Scadding, David C. Wraith, Mamidipudi Thirumala Krishna
Background: Allergic rhinitis (AR) affects approximately 10% of Indian adults, but its clinical and biological heterogeneity remains poorly defined. Objective: We sought to characterize AR phenotypes in South Indian adults using clinical features, spirometry, fractional exhaled nitric oxide (Feno), skin prick tests, blood biomarkers, and cluster analysis. Methods: This was a prospective observational study of 122 patients (≥18 years old) with AR with or without asthma attending a South Indian tertiary allergy clinic and 50 asymptomatic nonatopic control subjects. Participants underwent standardized symptom/exposure assessments, spirometry, Feno, blood counts, serum IgE, and skin prick tests to 10 aeroallergens. Principal component analysis, correlation networks, and unsupervised k-means clustering were applied to define phenotypes. Results: (Bermuda pollen), and cockroach. Conclusions: This study showed 3 distinct AR clusters with high dust mite sensitization alongside cosensitization with cockroach, weed, and Bermuda pollens. Multicenter studies are warranted to further refine AR clusters, including tissue-level biomarker profiling and relevance to pharmacotherapy and immunomodulatory therapies.