Coincidence of pollen season with the first fetal trimester together with early pet exposure is associated with sensitization to cat and dog allergens in early childhood: A Finnish population-based study

The association of timothy grass allergy and cat ownership on cat sensitization

Background: Pollen hypersensitivity might be a determining factor for other nonseasonal allergens because it may indicate deviation of the immune system toward T-helper type 2 activity and immunoglobulin E sensitivity. Objective: To investigate whether timothy grass pollen allergy may be a predictive factor for cat sensitization and whether there is an association between sensitivity to both allergens. Method: A retrospective review was made of patients with symptoms of rhinitis. The skin-prick test results and cat ownership status of the patients were analyzed. On the basis of the skin-prick test results with Phleum pratense (timothy grass) and other pollens, the patients were analyzed in two groups: "timothy allergic" and "non-timothy allergic." Results: A total of 383 patients with the diagnosis of rhinitis were included in the study, which comprised 213 (55.6%) in the timothy allergic group and 170 (44.4%) in the non-timothy allergic group. The frequency of cat sensitization was significantly higher in the patients in the timothy allergic group compared with those without timothy grass allergy (33.8% versus 12.3%; p < 0.001). No significant difference was determined between the two groups in terms of cat ownership (p = 0.63). In the logistic regression analysis, cat ownership (adjusted odds ratio [OR] 23.07 [95% confidence interval {CI}, 7.72-68.91]) and timothy allergy (adjusted OR 7.72 [95% CI, 3.16-18.86]) were associated with an increased risk of cat sensitization. Conclusion: Timothy grass allergy may play a role in the development of cat sensitization; however, further research is needed to clarify these associations and the underlying mechanisms.

Delivery mode and the incidence of atopic sensitization and food allergy in a Finnish child population

BACKGROUND

Caesarean section (CS) has been associated with an increased risk of subsequent atopic diseases, particularly asthma and respiratory allergies, but controversial findings have also been reported. Our aim was to clarify the association between the delivery mode and longitudinal (atopic) outcomes.

METHODS

The target population was identified from the population register and comprised all children born between 2001 and 2006 and living in the province of South Karelia, Finland (N = 5564). The information on the delivery mode was available for 5552 children from the Finnish Medical Birth Register. Results of allergy tests (skin prick tests, specific IgE and open food challenges, OFCs) were collected from patient records of all healthcare units in the area.

RESULTS

By 12 years of age, the cumulative incidence of atopic sensitization was 15% for those born by normal vaginal delivery (VD), 20% (adjusted RR 1.28; 95% CI 0.99-1.65) by assisted VD, 20% (adjusted RR 1.28; 95% CI 1.02-1.61) by elective CS and 20% (adjusted RR 1.24; 95% CI 0.99-1.56) by others, for example emergency CS. Among the offspring of mothers without atopic diseases, the incidence of food allergy (positive OFC) was 6% for those born by elective CS and 2% for those born by normal VD (adjusted RR 2.41; 95% CI 1.19-4.88), while the respective incidences were 5% and 6% (adjusted RR 0.82; 95% CI 0.33-2.06) among the offspring of mothers with atopic diseases.

CONCLUSION

By adolescence, the cumulative incidences of atopic sensitization was highest among those born by assisted VD or CS. The incidence of food allergy was highest among those born by elective CS among the offspring of mothers without atopic diseases.

Atopic diseases of the parents predict the offspring's atopic sensitization and food allergy

BACKGROUND

In genetic studies and selected study populations, parental atopy has been associated with atopic diseases in offspring. Our aim was to identify the association between parental atopic diseases and the offspring's atopic sensitization and food allergies, and their effect modifications due to the offspring's sex.

METHODS

The study population (N = 5564) (born between 2001 and 2006) was identified from the population register and live in the province of South Karelia, Finland. Questionnaire-based information on parental atopic diseases was available for 3592 children. The results of skin prick tests, specific IgE tests, and open food challenges (OFC) were collected from patient records.

RESULTS

By 12 years of age, the cumulative incidence of sensitization to food (14% vs 7%, hazard ratio 2.13; 95% CI 1.68-2.69), animal (10% vs 6%, 1.86; 1.42-2.44), and pollen allergens (12% vs 6%, 2.43; 1.85-3.19), as well as food allergies (positive OFC, 5% vs 2%, 2.28; 1.57-3.33), was higher in the offspring of parents with atopic diseases. The cumulative incidence for pollen sensitization was twofold higher for the female offspring of parents with atopic diseases than those of parents without, while it was almost threefold higher among males. The association between parental pollen allergy and the offspring's pollen sensitization was modified by sex according to additive scale estimates (RERI 1.03; 95% CI 0.13-1.91).

CONCLUSION

Until adolescence, parental atopic diseases have a relatively strong association with the offspring's, particularly male offspring's, atopic sensitization, and food allergies. A pronounced association was found between parental pollen allergy and the male offspring's pollen sensitization.

Developments in the field of clinical allergy in 2018 through the eyes of Clinical and Experimental Allergy, Part II

In this article, we describe developments in the field of clinical allergy as described by Clinical and Experimental Allergy in 2018; epidemiology, asthma and rhinitis, clinical allergy and allergens are all covered.

Occurrence of pollen season at the end of the first trimester predicts clinical atopic diseases in the offspring: A Finnish population-based study

OBJECTIVE

To evaluate the association between potential exposure to different pollen concentrations at the 11th fetal week and subsequent clinical atopic diseases.

STUDY DESIGN AND SETTING

Parents of 1- to 4-year-old children (N = 3035) returned a questionnaire regarding physician-diagnosed atopic diseases. The children were born between 2001 and 2005 in the province of South Karelia, Finland. Results of allergy tests were collected from patient records in the area.

RESULTS

The prevalence of atopic diseases with sensitisation was higher in children whose 11th fetal week occurred during pollen rather than non-pollen season: atopic eczema 6.3% vs. 4.3% (adjusted odds ratio, aOR 1.58, 95% CI 1.10─2.28), food allergy 5.7% vs. 3.9% (1.63; 1.12─2.38), respiratory allergy or asthma 3.7% vs. 2.2% (2.03; 1.24─3.33) and any atopic diseases 7.4% vs. 5.5% (1.48; 1.07─2.05), respectively. Respectively, the prevalence was higher in the children exposed to high rather than low tree pollen concentrations (>1000 vs. <10 particles/m³) at the 11th fetal week: 12.1% vs. 4.4% (3.35; 1.89─5.95), 12.1% vs. 3.9% (3.77; 2.11─6.72), 4.7% vs. 2.5% (2.95; 1.21─7.20) and 14.0% vs. 5.7% (3.15; 1.86─5.35).

CONCLUSION

Coincidence of potential exposure to high tree pollen concentrations at the 11th fetal week is associated with subsequent clinical atopic diseases with sensitisation.

Bedroom Allergen Exposure Beyond House Dust Mites

PURPOSE OF REVIEW

The review provides insight into recent findings on bedroom allergen exposures, primarily focusing on pet, pest, and fungal exposures.

RECENT FINDINGS

Large-scale studies and improved exposure assessment technologies, including measurement of airborne allergens and of multiple allergens simultaneously, have extended our understanding of indoor allergen exposures and their impact on allergic disease. Practical, streamlined methods for exposure reduction have shown promise in some settings, and potential protective effects of early-life exposures have been further elucidated through the investigation of specific bacterial taxa. Advances in molecular allergology have yielded novel data on sensitization profiles and cross-reactivity. The role of indoor allergen exposures in allergic disease is complex and remains incompletely understood. Advancing our knowledge of various co-exposures, including the environmental and host microbiome, that interact with allergens in early life will be crucial for the development of efficacious interventions to reduce the substantial economic and social burden of allergic diseases including asthma.