Control of obesity-associated bronchial asthma depending on an age of debut and Arg16Gly polymorphism of the β2-adrenoreceptor gene

Abstract

Objective — to analyze the control level of obesity‑associated bronchial asthma (BA) with early or late onset depending on Arg16Gly polymorphism of the b2‑adrenoreceptor gene (b2‑AP). Materials and methods. The study involved 553 BA patients and 95 apparently healthy individuals. They were divided into 2 groups: group I included 282 patients with late‑onset asthma (late‑onset asthma phenotype) and group II included 271 patients with early‑onset asthma (early‑onset asthma phenotype). The study has been approved by the Bioethics Committee of Medical Institute of Sumy State University. Arg16Gly polymorphism in the b2‑adrenoceptor gene (rs1042713) was determined using polymerase chain reaction‑restriction fragment length polymorphism analysis. ACQ‑5 questionnaire was used to assess the level of BA control. Statistical analysis of obtained results was performed using SPSS‑17 program. Results. The total BA control was reveled in 189 patients (34.2 %), partial — in 162 (29.3 %), and absence of control in 202 (36.5 %) subjects. Among the examined BA patients, 152 (27.5 %) subjects had normal body weight, 206 (37.3 %) were overweight and 195 (35.2 %) suffered from obesity. The visceral type of obesity was verified in all patients. The results of the analysis of control depending on the body mass index (BMI) showed significantly lower levels in BA patients with obesity as compared with patients with normal weight and overweight (all p = 0.001). At the same time, the level of control was lower in patients with early BA with obesity as compared with those with late BA, but did not differ significantly (p = 0.33). The dependence of the control level on the Arg16Gly polymorphism of the b2‑AR gene in obese patients with early BA was established. In the presence of the Gly/Gly genotype of the Arg16Gly b2‑AR gene polymorphism, the control level in patients with early‑onset BA was significantly lower than that in carriers of the Arg/Gly and Arg/Arg genotypes. The control of late‑onset BA did not depend on the Arg16Gly polymorphism of the b2‑AR gene. Conclusions. A lower level of control was revealed in obese BA patients compared to overweight patients and subjects with normal body weight. The control score was lower in obese patients with early onset asthma compared to asthma with late BA onset. The level of control depended on the Arg16Gly polymorphism of the b2‑AR gene only in obese patients with early BA onset. The Gly/Gly genotype of the Arg16Gly polymorphism of the b2‑AR gene was associated with a lower level of control in patients with early onset BA.