Prevalence of asthma and allergies in children from the Greek-Cypriot and Turkish-Cypriot communities in Cyprus: a bi-communal cross-sectional study.

BACKGROUND: The Greek-Cypriot (G/C) and Turkish-Cypriot (T/C) communities have lived apart since 1974, with the former presumably adopting a more westernized way of life. We estimated the prevalence of asthma and allergies among children in the two communities and investigated differences in socio-demographic and lifestyle risk factors. METHODS: The ISAAC questionnaire was completed by 10156 children aged 7-8 and 13-14 years. Relative differences in asthma and allergic symptoms between the two communities were expressed as odds ratios (OR), estimated in multivariable logistic regression models before and after adjusting for participants' risk characteristics. RESULTS: In contrast to our original speculation, consistently lower prevalence rates were observed for respiratory outcomes (but not eczema) among G/C compared to T/C children in both age-groups. For instance, the prevalence of current wheeze among 7-8 year-olds was 8.7% vs 11.4% (OR = 0.74, 95%, CI: 0.61, 0.90) and of current rhinoconjuctivitis 2.6% vs 4.9% (OR = 0.52, 95% CI: 0.37, 0.71). Surprisingly, the proportion reporting family history of allergy was almost double in the G/C community. With the exception of early life nursery attendance, several protective factors were more prevalent amongst T/C, such as bedroom sharing, less urbanized environment and exposure to farm animals. In contrast, exposure to tobacco smoke was more frequent in the T/C community. Controlling for risk factors did not account for the observed lower prevalence of current wheeze (in the younger age-group) and rhinoconjuctivitis (in both age-groups) among G/C children while differences in the prevalence of eczema between the two communities were no longer statistically significant. CONCLUSIONS: A mixed picture of potential risk factors was observed in the two communities of Cyprus, not consistently favoring one over the other community since, for example, bedroom sharing and rural living but also exposure to tobacco smoke were more common among T/C children. Investigated risk factors do not fully account for the lower prevalence of asthma and allergies among G/C children, especially against a background of higher family history of allergy in this community.

FcgammaRIIIa-V/F 158 polymorphism in Turkish children with asthma bronchiale and allergic rhinitis.

Fc receptors (FcR) play an important role in immune regulation. This might be linked to the variability in immune response, therefore relating to the pathogenesis of atopic diseases. The aim of the present study was to evaluate the FcgammaRIIIa gene polymorphism in Turkish children with asthma and allergic rhinitis. The study included 364 atopic children (184 bronchial asthma, 180 allergic rhinitis) and 234 healthy subjects as the control group, aged between 5 to 16 years. Patients were recruited from outpatient clinics of allergy and general pediatric care. Plasma IgE concentrations were measured by immunoassays and skin prick test was done in children with atopic diseases. The FcgammaRIIIa gene polymorphism was determined using the polymerase chain reaction method. Distribution of V158V genotype was significantly different among patient groups compared to controls (for asthmatic children OR: 5.33, 95% CI: 2.80-10.23, p < 0.001; for allergic rhinitis OR: 3.25, 95% CI: 1.75-6.07, p = 0.001). Distribution of 158 V allele was significantly different among asthmatic children (OR: 2.20, 95% CI: 1.65-2.92, p < 0.001) and allergic rhinitis patients (OR: 1.77, 95% CI: 1.32-2.35, p < 0.001) compared to healthy controls. Our study shows that the V158V genotype in FcgammaRIIIa gene polymorphism may be a genetic risk factor for the development of atopic diseases.

Development of new sensitizations in asthmatic children monosensitized to house dust mite by specific immunotherapy.

It has been hypothesized that specific immunotherapy (SIT) significantly decreases the development of new allergen sensitizations in mono-sensitized patients. In this study, we evaluated the effect of SIT on the development of new allergen sensitizations in 129 asthmatic children mono-sensitized to house dust mite. SIT was accepted by only 70 of them (SIT group). The remaining 59 children were treated only with medication (control group). At the end of the study we found that 33% of all patients developed new sensitizations. Surprisingly, the prevalence of new sensitizations was significantly higher in the SIT group (45.5%) than in the control group (18.1 %). Ash tree (Fraxinus excelsior), Olive and Meadow fescue (Festuca elatior) were the most common allergens responsible for the new sensitizations. We conclude that SIT did not prevent the onset of new sensitizations in asthmatic children mono-sensitized to house dust mite.

The Fc gammaRIIa polymorphism in Turkish children with asthma bronchial and allergic rhinitis.

OBJECTIVE: The aim of the present study was to evaluate the Fc gammaRIIa polymorphism in Turkish children with atopic asthma and allergic rhinitis. DESIGN AND METHODS: In this study, 372 atopic children (192 asthma bronchial, 180 allergic rhinitis) between ages of 5 and 16 years old (11.3+/-2.9) who were followed at Aegean University Paediatric Allergy and Pulmonology Outpatient Clinics and 234 healthy subjects as the control group were included. The evaluation of subjects included routine biochemical blood analysis and allergic workup based on the following laboratory determinants. The Fc gammaRIIa polymorphism was determined using the polymerase chain reaction method. RESULTS: Distribution of R131R genotype was significantly different among patient groups compared to controls (for asthmatic children OR: 2.64 95%CI: 1.22-5.79, p=0.006; for allergic rhinitis OR: 2.58 95%CI: 1.18-5.71, p=0.009). Frequency of 131R allele was significantly different among patient groups compared to controls (for asthmatic children OR: 1.66 95%CI: 1.22-2.26, p=0.0007; for allergic rhinitis OR: 1.93 95%CI: 1.42-2.63, p=0.00001). CONCLUSION: This study shows that Fc gammaRIIa gene 131R allele represents an important genetic risk factor for bronchial asthma and allergic rhinitis susceptibility.