Atanas Koychev

Obesity in Bulgarian patients with chronic obstructive pulmonary disease

It has been well defined that obesity is strongly linked with several respiratory symptoms and diseases, but no convincing evidence has been provided for chronic obstructive pulmonary disease (COPD). In the current study, we aim to assess the possible prevalence of obesity in patients with COPD in a cross-sectional case–control study of individuals from the region of Stara Zagora, Bulgaria, and to explore whether the body mass has some effect on the lung function of COPD patients. The study included 158 patients with COPD (Global Initiative for Chronic Obstructive Lung Disease (GOLD) II, III, and IV stages) and 123 individuals unaffected by the disease (control). A higher frequency of obesity compared to the controls (20.3%) was observed in patients with COPD (29.1%, p = 0.093), especially in those with GOLD II stage (37.7%, p = 0.009). Prevalence of obesity was highest in COPD GOLD II, followed by GOLD III and IV stages (p = 0.068). When diabetes was considered as confounding factor, we found a significant prevalence of obesity in COPD patients than the controls with diabetes (p = 0.031). Interestingly, there was a statistically significant moderate positive correlation between the body mass index and forced expiratory volume in one second as a percentage of predicted value in the whole patients’ group (R = 0.295, p = 0.0002) as well as in the subgroups of GOLD II (R = 0.257, p = 0.024) and GOLD III COPD (R = 0.259, p = 0.031).The results of our study propose that the increased body mass, particularly obesity is frequent comorbidity to COPD, especially to less severe diseases. Moreover, the results suggest that the higher body weight may provide some protection against the impairment of lung functions in patients with stable COPD.

Single Nucletide Polymorphisms in Gene of IL-1Beta in Bronchial Asthma

ABSTRACT Bronchial asthma is a common chronic lung disease that is driven by abnormal inflammatory reactions in the airways in response to the complex interaction between genetics and environmental factors. The underlying inflammation in asthma is manifested by prominent eosinophil infiltration and Th2 inflammatory mediators; however the pro-inflammatory cytokines, particularly IL-1β, have also been found in increased amount in the sputum and BAL in individuals with bronchial asthma, especially in more severe state. Therefore, IL-1β is considered to be of importance in pathogenesis of this condition as the protein level of the cytokine is finely regulated by variety of factors, including genetics. The IL1B gene displays many SNPs both in promoter and coding regions, which have been associated with IL-1β production. In the current case-control study we investigated -511C>T (rs16944) promoter polymorphism and +3953C>T (rs1143634) silent polymorphism in exon 5 of IL1B and their haplotypes as candidate risk factors of Bronchial asthma in Bulgarian population. We genotyped 47 patients with bronchial asthma and 174 control individuals using Taqman genotyping assay for IL1B -511C>T SNP and PCR-RFLP-based method for +3953C>TSNP. We did not observe statistically significant differences in genotype frequencies of IL1B -511C>T and IL1B +3953C>T between controls and patients with asthma (p=0.065 and p=0.987). However, the minor T allele of IL1B -511C>T was less frequently found in the controls (0.305) compared to the patients with asthma (0.415, p=0.0002). Carriers of IL1B -511T allele (TT or TC genotypes) appeared to have 2.25-fold higher risk for Bronchial asthma (95% CI: 1.127–4.498, p=0.019). The performed estimations of IL1B haplotypes did not reveal any difference in the haplotype frequencies between controls and patients with asthma (p=0.270). However, the T_C haplotype, constructed by alleles found to determine enhanced expression of IL-1β, appeared to be associated with higher risk of asthma (OR 1.78, 1.04–3.03, p=0.035) compared to the most common C_C haplotype. Based on the results of the current study we suggest that the -511C>T promoter polymorphism and +3953C>T silent polymorphism in exon 5 of IL1B may influence the genetic predisposition of Bronchial asthma in Bulgarian population, as the carriers of alleles and haplotypes supposed to define higher IL-1β protein levels are more susceptible for this lung diseases.