Difference in Frequency of Aeroallergen Hypersensitivity in Patients from Urban Versus Rural Households
Year: 2025
Type: article
Study design: Observational Study
Abstract: OBJECTIVE: To indirectly evaluate the hygiene hypothesis in the Pakistani population by assessing the difference in aeroallergen hypersensitivity frequency among patients from urban and rural households. STUDY DESIGN: Cross-sectional, descriptive study. Place and Duration of the Study: Department of Immunology, The Armed Forces Institute of Pathology (AFIP) / NUMS, Rawalpindi, Pakistan, from January to December 2023. METHODOLOGY: Patients advised skin prick test (SPT) by their treating clinicians and meeting the inclusion criteria were included. SPT was performed using six common inhalational allergens, with negative (normal saline) and positive (0.1% histamine hydrochloride) controls. Results were assessed after 15 minutes, and a wheal diameter >3 mm was considered positive. Aeroallergen sensitisation frequencies were compared between urban and rural populations using the Chi-square test. A p-value of <0.05 was considered statistically significant. RESULTS: Out of 312 patients, 106 (34%) tested positive for SPT, comprising 60 (57%) males and 46 (43%) females. Among these, 44 (41%) were polysensitised to two or more than two allergens. The most prevalent allergens were house dust mite mix (59%) and Cannabis (31%), while Aspergillus was the least common (8%). A statistically significant difference (p = 0.008) was observed in aeroallergen sensitisation prevalence between urban and rural dwellers, with urban patients showing higher sensitisation rates. CONCLUSION: The findings support hygiene hypothesis, demonstrating a higher frequency of aeroallergen hypersensitivity in urban populations compared to rural counterparts. The role of environmental exposures in immune system modulation underscores the impact of urbanisation on allergic diseases in the Pakistani setting. KEY WORDS: Aeroallergens, Allergy, Hygiene hypothesis, Sensitisation, Skin prick test, Urbanisation.
Language: English
Subfield: Immunology and Allergy
Field: Medicine
Domain: Health Sciences
Open Access status: diamond
OpenAlex ID: W4409512864