BACKGROUND

Leptin may play a critical role in airway inflammation. However, it has rarely been evaluated in rhinitis with different aetiology. This study aimed to compare the serum leptin levels between allergic rhinitis (AR) and non-allergic rhinitis (NAR).

METHODS

Patients with chronic rhinitis were classified due to skin prick (ALK-Abello/Madrid) and/or serum specific immunoglobulin E tests (UniCAP 100-Pharmacia), against to aeroallergens if concordant with symptoms.

RESULTS

A total of 398 patients with a mean age of 29.03yr were recruited and grouped as AR and NAR. Mean serum leptin levels were similar in patients with NAR and AR, as well as in patients with and without asthma, but were significantly higher in females than males in both groups. Also, leptin levels were significantly higher in obese than non-obese patients in AR. In correlation analysis, leptin levels were found to be correlated with female gender, older age and high BMI in the whole group. Despite the higher TNSS in patients with AR compared to NAR, there was no association of leptin levels with TNSS, severity and seasonality of symptoms, and allergen sensitization. In logistic regression analysis; younger age and high serum leptin levels were found to be independent predictors for the diagnosis of AR.

CONCLUSIONS

We conclude that female patients with high BMI are more prone to AR probably due to immunological effects of adipose tissue, in addition to hormonal factors. This study showed that leptin measurement has limited value as a sole diagnostic tool to differentiate AR and NAR.