A Prospective Study on the Association between Oxidative Stress and Duration of Symptoms in Allergic Rhinitis.

Oxidative stress has been known to play an important role in inflammatory responses of allergic rhinitis. We investigated the association between degree of oxidative stress and severity of allergic rhinitis. A total 226 allergic rhinitis students were classified by a history of allergic rhinitis into groups according to number and duration of symptoms within the previous year. The total antioxidant status (TAS) and total oxidant status (TOS) levels were compared among groups. Mean TAS level (14.03 ± 9.09 mmol/L) in the group with more than six months of symptoms had a tendency to be higher (p = 0.068) than that of the group with fewer than six months (12.33 ± 8.83 mmol/L). There was no statistically significant difference in mean TAS or TOS level with number of symptoms (nasal congestion, itching, sneezing and watery rhinorrhea). A multivariate logistic regression showed that the adjusted odds ratio of TAS was 1.655 and the adjusted odds ratio of TOS was 0.972 in more than a six-month duration group. The TAS level was significantly associated with a more than six-month symptom duration (p = 0.034). Our results suggest that antioxidant activity increased when allergic rhinitis became chronic and further research will be needed considering the disease severity.