(HealthDay News) — Patients with allergic rhinitis may have an increased risk of developing nasopharyngeal carcinoma (NPC), according to a Taiwanese study published in the March issue of Head & Neck.
Kuen-Tze Lin, M.D., from the National Defense Medical Center in Taipei, Taiwan, and colleagues used a Taiwan Longitudinal Health Insurance Database (2000 to 2005) to identify 67,532 patients with allergic rhinitis (allergic rhinitis cohort) and 135,064 age- and sex-matched controls.
After adjusting for possible confounding factors, the researchers observed a 2.33-fold higher risk of developing NPC in the allergic rhinitis cohort compared to the control cohort. There was a correlation between the frequency of allergic rhinitis visits and the risk of subsequent NPC, with patients having four or more allergic rhinitis visits per year having a significantly elevated risk of developing NPC.
“Although the association between allergic rhinitis and NPC is apparent, the mechanism underlying this association is a focus of ongoing research,” the authors write. “A possible explanation is that chronic repeated airway stimulation and inflammation, reduced mucociliary clearance, and epithelial cell changes after the deposition of allergens in the nasopharynx may promote a malignant change after a certain induction time.”