Saliva Pepsin Levels Are a Potential Risk Factor for Asthma in Children With Allergic Rhinitis

Allergic rhinitis and asthma are commonly co-existing conditions, particularly in children. While the relationship between these 2 conditions has been extensively studied, research to identify specific risk factors that may exacerbate asthma in children with allergic rhinitis has been ongoing.

“Gastroesophageal reflux disease (GERD) has been considered a risk factor for asthma and a trigger for asthma attacks in children,” investigators of a study in the Journal of Allergy and Asthma wrote. They went on to explain that “certain drugs routinely used for GERD may have the potential to enhance lung volumes in respiratory function tests and alleviate asthma symptoms” and that pepsin, consistently found in all refluxate, “could theoretically be an indicator of asthma risk.”

Researchers conducted a prospective study on a group of 20 children newly diagnosed with allergic rhinitis and asthma and 20 matched controls with only allergic rhinitis to examine whether saliva pepsin concentration (SPC) could be a risk factor for the occurrence and unfavorable control of asthma in children with allergic rhinitis.

Various assessments were conducted, including fractional exhaled nitric oxide (FeNO) measurement, lung function tests, and evaluation of asthma control using the Childhood Asthma Control Test score. SPC measurement was performed in both groups to examine its association with asthma and allergic rhinitis.

The results revealed a significant difference in SPC between the asthma and control groups, with significantly higher SPC values in patients with allergic rhinitis and asthma (165.0 ng/mL vs 68.4 ng/mL; P<.001).

Furthermore, in both the allergic rhinitis and asthma groups, SPC was found to be independently associated with FeNO, as well as lung function parameters such as the ratio of forced expiratory volume in 1 second to forced vital capacity (FVC) and forced expiratory flow at 50% and 75% of FVC.

Additionally, the severity of nasal symptoms, as evaluated by the visual analogue scale, was independently associated with lung function parameters and asthma control scores.

The investigators concluded that the results of their study “indicated a significant role of direct pepsin exposure in the pathogenesis and progression of childhood allergic asthma” and confirmed their hypothesis that the SPC value can be considered as a risk factor for asthma in children with allergic rhinitis.