The effect of the type of inhaled anti-asthmatic therapy on the properties of saliva in children – a phantom study

Introduction
Asthma is the most common chronic childhood disease, mainly treated with inhaled steroid anti-inflammatory drugs (ICSs) and inhaled bronchodilators. Unfortunately, current literature emphasizes their negative effect on the condition of soft tissues of the oral cavity and hard dental tissues. Objectives: The aim of the study was to assess the effect of types of inhaled anti-asthmatic drugs on the proper­ties of saliva in children.

Material and methods
Study group included 114 asthmatics and 94 healthy patients between the age of 3 and 17. Information about the age of onset, severity of asthma, use of anti-asthmatic medications, duration of the therapy, method of drugs’ administration, and number of their application were recorded. The severity of asthma was assessed by a pediatrician. Saliva was collected for resting pH, buffering capacity, hydration, saliva quantity, and viscosity measurements using saliva-check buffer kit (GC). Student’s t-test, c2 test, Mann-Whitney U test, and Spearman’s correlation coefficient were used, with a significance level of p < 0.05.

Results
Asthmatics appeared to be characterized by significantly lower average values of saliva quantity (p = 0.0064), buffering capacity (p = 0.0002), and viscosity (p = 0.0094) than controls. Spearman’s rank correlation revealed a negative correlation between steroid dose, therapy duration, and the use of dry powder inhalers (DPIs) on saliva quantity. Moreover, combination therapy with β2-agonists and DPIs reduces hydration of lip mucosa. Finally, the use of DPIs increases the viscosity of saliva.

Conclusions
The study shows that inhaled anti-asthmatic medications have a considerable effect on salivary properties.