Is Gly16Arg β2 Receptor Polymorphism Related to Impulse Oscillometry in a Real-Life Asthma Clinic Setting?

Area of Science:

• Pharmacogenetics
• Respiratory Medicine
• Pulmonary Function Testing

Background:

• The Gly16Arg polymorphism in the beta2-adrenergic receptor gene is studied for its potential influence on asthma management.
• Impulse oscillometry (IOS) provides objective measures of airway resistance and reactance.

Purpose of the Study:

• To investigate the association between the Gly16Arg beta2-receptor genotype and impulse oscillometry (IOS) outcomes in a real-world clinical setting.
• To determine if Gly16Arg genotype impacts asthma control and medication use in patients on inhaled corticosteroids (ICS) with or without long-acting beta-agonists (LABA).

Main Methods:

• A cohort of 112 patients with persistent asthma on ICS ± LABA were genotyped for the Gly16Arg polymorphism.
• IOS parameters including total airway resistance (R5), peripheral airway resistance (R5-R20), and reactance were measured.
• Asthma Control Questionnaire (ACQ-5) scores and salbutamol use were recorded and compared between GlyGly and Arg-carrying (ArgArg/ArgGly) genotype groups.

Main Results:

• No significant differences were observed in any IOS outcomes (R5, R20, R5-R20, reactance, AX, RF), ACQ-5 scores, or salbutamol use between the GlyGly and Arg-carrying genotype groups.
• The allelic risk for poorly controlled asthma (ACQ > 1.5) or abnormal peripheral airway resistance (R5-R20 > 0.07 kPa/l.s) showed no significant association with the presence of Arg copies.

Conclusions:

• In patients with persistent asthma treated with ICS ± LABA in a real-life setting, the Gly16Arg beta2-receptor genotype is not associated with impulse oscillometry measures.
• The findings suggest that Gly16Arg genotype does not predict airway resistance or asthma control in this patient population.