Psychological well-being of children and adolescents with inflammatory bowel disease.

OBJECTIVES: Prior studies on the psychological well-being in pediatric inflammatory bowel disease (PIBD) have reported controversial results. Our aim was to compare the psychological well-being and lifestyle factors in patients with PIBD and their controls and to assess the role of contributing disease characteristics. METHODS: This cross-sectional study included 60 PIBD patients aged 6-17 years (26 with Crohn's disease [CD], 34 with ulcerative colitis [UC] or unclassified colitis [IBD-U]) from two university hospitals in Finland, and their age- and sex-matched healthy controls. Psychological well-being was assessed with three measures: a questionnaire on overall psychological well-being (PSWB) and for adolescents also Beck Depression Inventory (BDI Ia) and Perceived Stress Scale (PSS). In addition to disease characteristics and pain, we assessed physical activity, sleep, screen time, and social well-being. RESULTS: Controls were more likely of stressing more (odds ratio [OR] = 3.67, 95% confidence interval [95% CI] 95% CI = 1.02-13.14), but other measures of psychological well-being did not differ statistically significantly between patients and controls. In CD, a clinically more active disease associated with inferior psychological well-being in adolescents (BDI [ρ = 0.63, p = 0.021], PSS [ρ = 0.70, p = 0.008], PSWB [ρ = 0.56, p = 0.049]). Longer time from diagnosis correlated with better psychological well-being on BDI (ρ = -0.39, p = 0.024) and PSS (ρ = -0.38, p = 0.034). Lifestyle was more sedentary in PIBD (less physical activity in children OR = 0.82, 95% CI = 0.68-0.99 and more screen time in adolescents OR = 1.18, 95% CI = 1.00-1.40). CONCLUSION: Although the clinical features of PIBD are potentially a burden for psychological well-being, many young patients cope well with their disease. Individual variation in well-being is remarkable, making supportive measures challenging.

Increased adiposity in juvenile idiopathic arthritis - A comparison of the bioelectrical impedance analysis and dual-energy X-ray absorptiometry for the assessment of body composition.

AIM: Higher adiposity and increased risk of cardiovascular diseases have been reported in juvenile idiopathic arthritis (JIA), but body composition measurements have produced inconsistent results. This controlled cross-sectional study assessed body composition with two methods to evaluate adiposity in children with JIA. METHODS: We measured body composition by dual- energy X-ray absorptiometry (DXA) and bioelectrical impedance analysis (BIA) from 79 JIA-patients in two Finish university hospitals in 2017-2019. Their age- and sex-matched controls (n = 79) were selected from the Physical Activity and Nutrition in Children- study and through National Registry. RESULTS: Body fat percentage measured by BIA was higher (mean, SD) in patients compared to controls (23.1 ± 9.3% vs. 20.1 ± 7.5%, p = 0.047). Also, using DXA, there was a tendency of higher body fat percentage in patients (27.1 ± 9.1% vs. 24.6 ± 8.6, p = 0.106). BIA and DXA showed strong correlation (r from 0.810 to 0.977) in all body composition variables. CONCLUSION: Increased adiposity was observed in patients with JIA. Evaluation of body composition should be included in the multidisciplinary care of JIA to reduce the possible risk of cardiovascular diseases in adulthood. BIA could be a useful tool for assessing body composition due to its clinical availability and safety.

Comparison of remote learning methods to on-site teaching -randomized, controlled trial.

BACKGROUND: In the digitalized world, there is a need for developing new online teaching and learning methods. Although audio and video recordings are increasingly used in everyday learning, little scientific evidence is available on the efficacy of new online methods. This randomized trial was set out to compare the learning outcomes of online and classroom teaching methods in training healthcare students to diagnose breathing difficulties in children. METHODS: In total, 301 students of medicine (N = 166) and nursing (N = 135) volunteered to participate in this total sampling study in 2021-2022. The students were randomized into four groups based on teaching methods: classroom teaching (live, N = 72), streamed classroom teaching (live-stream, N = 77), audio recording (podcast, N = 79) and video recording (vodcast, N = 73). Each 45-minute lesson was taught by the same teachers and used the same protocol. The students participated an online test with their own electronic device at three distinct time points: prior to any teaching (baseline), immediately after teaching (final test), and five weeks later (long-term memory test). The test consisted of 10 multiple-choice questions on recognizing breathing difficulties from real-life videos of breathing difficulties in pre-school age. The test results scale ranged from - 26 to 28 points. Statistical analyses were performed using ANOVA multiple comparison and multiple regression tests. RESULTS: The mean scores (SD) of the final tests were 22.5 (5.3) in the vodcast, 22.9 (6.1) in the live, 20.0 (5.6) in the podcast (p < 0.05 vs. live) and 20.1 (6.8) in the live-stream group. The mean difference of test scores before and after the lesson improved significantly (p < 0.05) in all study groups, with 12.9 (6.5) in the vodcast, 12.6 (5.6) in the live, 10.9 (7.0) in the live-stream and 10.4 (6.9) in the podcast group. The improvement in test scores was significantly higher in the vodcast (p = 0.016) and the live (p = 0.037) groups than in the podcast group. No significant differences were found between the other groups. However, there was a nonsignificant difference towards better results in the vodcast group compared to the live-stream group. CONCLUSIONS: While the new online teaching methods produce learning, only video learning is comparable to team teaching in classrooms.

Early-life residential exposure to moisture damage is associated with persistent wheezing in a Finnish birth cohort.

BACKGROUND AND AIMS: Moisture damage increases the risk for respiratory disorders in childhood. Our aim was to determine whether early age residential exposure to inspector-observed moisture damage or mold is associated with different wheezing phenotypes later in childhood. METHODS: Building inspections were performed by civil engineers, in a standardized manner, in the children's homes-mostly single family and row houses (N = 344)-in the first year of life. The children were followed up with repeated questionnaires until the age of 6 years and wheezing phenotypes-never/infrequent, transient, intermediate, late onset, and persistent-were defined using latent class analyses. The multinomial logistic regression model was used for statistical analysis. RESULTS: A total of 63% (n = 218) had infrequent or no wheeze, 23% (n = 80) had transient and 9.6% (n = 21) had a persistent wheeze. Due to the low prevalence, results for intermediate (3.8%, n = 13) and late-onset wheeze (3.5%, n = 12) were not further evaluated. Most consistent associations were observed with the persistent wheeze phenotype with an adjusted odds ratio (95% confidence intervals) 2.04 (0.67-6.18) for minor moisture damage with or without mold spots (present in 23.8% of homes) and 3.68 (1.04-13.05) for major damage or any moisture damage with visible mold in a child's main living areas (present in 13.4% of homes). Early-age moisture damage or mold in the kitchen was associated with transient wheezing. CONCLUSION: At an early age, residential exposure to moisture damage or mold, can be dose-dependently associated especially with persistent wheezing phenotype later in childhood.

Microbial diversity in homes and the risk of allergic rhinitis and inhalant atopy in two European birth cohorts.

BACKGROUND: Microbial exposures in early childhood direct the development of the immune system and their diversity may influence the risk of allergy development. We aimed to determine whether the indoor microbial diversity at early-life is associated with the development of allergic rhinitis and inhalant atopy. METHODS: The study population included children within two birth cohorts: Finnish rural-suburban LUKAS (N = 312), and German urban LISA from Munich and Leipzig study centers (N = 248). The indoor microbiota diversity (Chao1 richness and Shannon entropy) was characterized from floor dust samples collected at the child age of 2-3 months by Illumina MiSeq sequencing of bacterial and fungal DNA amplicons. Allergic rhinitis and inhalant atopy were determined at the age of 10 years and analyzed using logistic regression models. RESULTS: High bacterial richness (aOR 0.19, 95%CI 0.09-0.42 for middle and aOR 0.12, 95%CI 0.05-0.29 for highest vs. lowest tertile) and Shannon entropy were associated with lower risk of allergic rhinitis in LISA, and similar trend was seen in LUKAS. We observed some significant associations between bacterial and fungal diversity measured and the risk of inhalant atopy, but the associations were inconsistent between the two cohorts. High bacterial diversity tended to be associated with increased risk of inhalant atopy in rural areas, but lower risk in more urban areas. Fungal diversity tended to be associated with increased risk of inhalant atopy only in LISA. CONCLUSIONS: Our study suggests that a higher bacterial diversity may reduce the risk of allergic rhinitis later in childhood. The environment-dependent heterogeneity in the associations with inhalant atopy - visible here as inconsistent results between two differing cohorts - suggests that specific constituents of the diversity may be relevant.

NKG2D gene variation and susceptibility to viral bronchiolitis in childhood.

BACKGROUND: Genetic factors associated with bronchiolitis are inadequately characterized. We therefore inspected a selected subpopulation of our previous genome-wide association study (GWAS) of bronchiolitis for overlap with known quantitative trait loci (QTLs) to identify susceptibility loci that potentially affect mRNA and protein levels. METHODS: GWAS included a Finnish-Swedish case-control population (n = 187), matched for age and site. We integrated GWAS variants (p < 10-4) with QTL data. We subsequently verified allele-specific expression of identified QTLs by flow cytometry. Association of the resulting candidate loci with bronchiolitis was tested in three additional cohorts from Finland and Denmark (n = 1201). RESULTS: Bronchiolitis-susceptibility variant rs10772271 resided within QTLs previously associated with NKG2D (NK group 2, member D) mRNA and protein levels. Flow cytometric analysis confirmed the association with protein level in NK cells. The GWAS susceptibility allele (A) of rs10772271 (odds ratio [OR] = 2.34) corresponded with decreased NKG2D expression. The allele was nominally associated with bronchiolitis in one Finnish replicate (OR = 1.50), and the other showed directional consistency (OR = 1.43). No association was detected in Danish population CONCLUSIONS: The bronchiolitis GWAS susceptibility allele was linked to decreased NKG2D expression in the QTL data and in our expression analysis. We propose that reduced NKG2D expression predisposes infants to severe bronchiolitis.

Long-term effects of pneumococcal colonization during early childhood wheezing.

BACKGROUND: Bacterial colonization during wheezing in early childhood has been associated with short-term relapses of wheezing, but no study has addressed the effects of Streptococcus pneumoniae colonization on long-term outcome of wheezing. The aim of the present study was therefore to evaluate whether pneumococcal (PNC) colonization during the first wheezing episode in early childhood is a determinant of asthma, atopy or lung function in the long term. METHODS: In 1981-82 83 infants were hospitalized for first wheezing episode at <24 months of age. PNC colonization was defined as positive nasopharyngeal aspirate for S. pneumoniae either in culture or antigen detection on hospital admission. Atopy and repeated wheezing or asthma were diagnosed on all follow-up visits from infancy until the age of 28-31 years. Spirometry was conducted at the ages of 8-10, 18-20 and 28-31 years. RESULTS: PNC colonization was found in 25/83 infants (30%) during hospitalization for wheezing in infancy. PNC colonization was not associated with later atopy, repeated wheezing, asthma or lung function at any time during the 30 year follow up. CONCLUSION: PNC colonization during the first wheezing episode in early childhood is not a determinant of subsequent wheezing or later asthma, atopy or lung function in childhood, adolescence or adulthood.

Low eosinophils during bronchiolitis in infancy are associated with lower risk of adulthood asthma.

BACKGROUND: Infant bronchiolitis may be the first manifestation of asthma. AIM: To evaluate the association of early-childhood risk or protective factors for asthma and lung function reduction in adults 30 years after bronchiolitis in infancy. METHODS: Forty-seven former bronchiolitis patients attended the clinical study at the median age of 29.5 years, including doctoral examination and measurement of post-bronchodilator lung function with flow-volume spirometry. Data on early-life risk factors including blood eosinophil counts on admission for bronchiolitis and on convalescence 4-6 weeks after bronchiolitis were available. RESULTS: Low blood eosinophil count <0.25 × 10E9/l on admission for bronchiolitis was a significant protective factor and high blood eosinophil count >0.45 × 10E9/l on convalescence was a significant risk factor for asthma in adulthood independently from atopic status in infancy. Parental asthma and high blood eosinophil count >0.45 × 10E9/l during bronchiolitis were significant risk factors for irreversible airway obstruction (FEV1/FVC ratio below the 5th percentile lower limit of normality after bronchodilation). CONCLUSION: Our adjusted analyses confirmed that eosinopenia during infant bronchiolitis predicted low asthma risk and eosinophilia outside infection predicted high asthma risk up to the age of 28-31 years. Parental asthma and eosinophilia during bronchiolitis were recognized as risk factors for irreversible airway obstruction.

Adults face increased asthma risk after infant RSV bronchiolitis and reduced respiratory health-related quality of life after RSV pneumonia.

AIM: To evaluate the association between hospitalisation for respiratory syncytial virus lower respiratory tract infection (RSV LRTI) in infancy and asthma, respiratory health-related quality of life and lung function at 28-31 years of age. METHODS: In 2010, we carried out a 30-year follow-up on 43 adults admitted to Kuopio University Hospital, Finland, for RSV LRTI, 27 for bronchiolitis and 16 for pneumonia, between 1981 and 1982. Together with 86 population-based controls, they completed the Saint George's Respiratory Questionnaire and underwent prebronchodilator (pre-BD) and post-BD spirometry tests to measure percentage of predicted forced vital capacity (FVC%), percentage of predicted forced expiratory volume in 1 sec (FEV1%) and percentage of predicted FEV1/FVC (FEV1/FVC%). RESULTS: Both the pre-BD and post-BD FEV1% and FEV1/FVC% were significantly lower in former RSV LRTI patients than in the controls. The bronchiolitis patients had more asthma in adulthood than the controls and pneumonia in infancy was associated with lower St George's Respiratory Questionnaire (SGRQ) scores. CONCLUSION: Respiratory tract infection LRTI hospitalisation in infancy was associated with an increased risk of permanent obstructive lung function reduction in adulthood. The asthma risk was higher after hospitalisation for bronchiolitis, than in the controls, and respiratory health-related quality of life was lower after hospitalisation for pneumonia.

No association between overweight and asthma or allergy in adolescence after wheezing in infancy.

AIMS: The aim of the study was to evaluate the association between weight status and asthma, allergy and respiratory symptoms in adolescents with bronchiolitis in infancy. SUBJECTS AND METHODS: At age 15-18 years, a questionnaire was sent to 96 study subjects hospitalized for wheezing at age <24 months and followed up subsequently. Sixty-seven (70%) of them answered. Weight and height data for body mass index (BMI) calculation were available in 60 (63%) cases. Asthma, allergy, respiratory symptoms and the use of asthma medication were compared between overweight or obese and normal weight groups constructed by age- and sex-specific BMI standard deviation scores (BMI-SDS). Population controls matched for sex, and birth month and place, were recruited for this study phase at age 15-18 years. RESULTS: Eleven (18.3%) study subjects were overweight (BMI-SDS >0.78 in males and >1.16 in females) and only 3 (5.0%) were obese (BMI-SDS >1.70 in males and >2.10 in females) at 16.5 (median) years of age. Overweight or obesity had no significant association with doctor-diagnosed or self-reported asthma, allergy or the use of inhaled corticosteroids. The negative results were confirmed by adjusted analyses. CONCLUSION: Weight status had no association with asthma or allergy in adolescence after wheezing in infancy.

Fungi in Early-Life House Dust Samples and the Development of Asthma: A Birth Cohort Study.

Rationale: Fungal exposure has been associated with predisposing and protective effects on the development of childhood asthma. Objectives: To study whether early-life house dust mycobiota composition is associated with the development of asthma. Methods: Mycobiota were determined by amplicon sequencing from 382 dust samples collected from living room floors 2 months after birth in homes of the LUKAS cohort. Asthma status by 10.5 years of age was defined from questionnaires and assigned as ever asthma (n = 68) or current asthma (n = 27). Inhalant atopy was clinically determined at the same age. ß-composition was analyzed using PERMANOVA-S, and asthma and atopy analyses were performed using discrete time hazard models and logistic regression, respectively. Results: The house dust mycobiota composition based on Bray-Curtis distance was different in the homes of children who later did or did not develop asthma. The first and the fourth axes scores of principal coordinates analysis based on Bray-Curtis were associated with ever asthma. Of the genera with the strongest correlation with these axes, the relative abundance of Boeremia, Cladosporium, Microdochium, Mycosphaerella, and Pyrenochaetopsis showed protective associations with asthma. None of these associations remained significant after mutual adjustment among the five genera or when mutually adjusted for other microbial cell wall markers and previously identified asthma-protective bacterial indices. Neither fungal α-diversity nor load was associated with asthma in the whole population, but higher fungal richness was a risk factor among children on farms. Higher fungal loads (measured via quantitative polymerase chain reaction) in house dust were associated with the risk of inhalant atopy. Conclusions: The results of our analyses from this well-characterized birth cohort suggest that the early-life house dust mycobiota in Finnish homes, characterized via DNA amplicon sequencing, do not have strong predisposing or protective effects on asthma development.

Impaired cardiorespiratory and neuromuscular fitness in children and adolescents with juvenile idiopathic arthritis: a cross-sectional case-control study in the era of biologic drug therapies.

BACKGROUND: In recent years, biologic drug therapies have altered the course of juvenile idiopathic arthritis (JIA) possibly also improving the patients' physical fitness. However, studies measuring both cardiorespiratory and muscular fitness in children with JIA are sparse and have failed to show consistent results. Our aim was to assess both cardiorespiratory and neuromuscular fitness and contributing factors in children and adolescents with JIA in the era of biologic drug therapies. METHODS: This cross-sectional study consisted of 73 JIA patients (25 boys, 48 girls) aged 6.8- 17.5 years and 73 healthy age- and sex-matched controls, investigated in 2017-2019. Cardiorespiratory fitness was assessed by maximal ergospirometry and neuromuscular fitness by speed, agility, balance, and muscle strength tests. RESULTS: Means (± SD) of maximal workload (Wmax/kg) and peak oxygen uptake (VO2peak/kg,) were lower in JIA patients than in controls (Wmax/kg: 2.80 ± 0.54 vs. 3.14 ± 0.50 Watts, p < 0.01; VO2peak/kg: 38.7 ± 7.53 vs. 45.8 ± 6.59 ml/min/kg, p < 0.01). Shuttle-run, sit-up and standing long jump test results were lower in JIA patients than in controls (p < 0.01). Mean (± SD) daily activity was lower (89.0 ± 44.7 vs. 112.7 ± 62.1 min/day, p < 0.05), and sedentary time was higher (427 ± 213 vs. 343 ± 211 min/day, p < 0.05) in JIA patients compared to controls. Physical activity and cardiorespiratory or neuromuscular fitness were not associated with disease activity. CONCLUSIONS: JIA patients were physically less active and had lower cardiorespiratory and neuromuscular fitness than their same aged controls with no JIA. Therefore, JIA patients should be encouraged to engage in physical activities as a part of their multidisciplinary treatment protocols to prevent adverse health risks of low physical activity and fitness.

Overweight does not increase asthma risk but may decrease allergy risk at school age after infantile bronchiolitis.

AIM: Increasing evidence suggests that overweight children are at increased risk of asthma. The association between weight gain and allergy is more complex. The aim was to evaluate the association between overweight or obesity and asthma, allergy, bronchial reactivity or atopic sensitization at school age in children with bronchiolitis in infancy. SUBJECTS AND METHODS: Eighty-one children hospitalized for bronchiolitis at <24 months of age attended control visits at 7.2 and 12.3 years of ages. The visits consisted of medical examinations, weight and height measurements, body mass index (BMI) calculations, skin prick tests and exercise challenge tests. BMI >1.3 SD from age- and gender-specific references meant overweight and BMI >2.0 SD obesity. RESULTS: Current or previous overweight or obesity did not increase the risk of asthma, allergy, bronchial reactivity or atopic sensitization at 7.2 or 12.3 years of age. Previous and current obesity decreased the risk of atopic dermatitis, and current overweight and obesity decreased the risk of sensitization to outdoor allergens at 12.3 years of age. CONCLUSION: Previous or current overweight does not increase asthma or allergy risk but current obesity may decrease allergy risk at school age after bronchiolitis in infancy.

Associations between dog keeping and indoor dust microbiota.

Living with dogs appears to protect against allergic diseases and airway infections, an effect possibly linked with immunomodulation by microbial exposures associated with dogs. The aim of this study was to characterize the influence of dog ownership on house dust microbiota composition. The bacterial and fungal microbiota was characterized with Illumina MiSeq sequencing from floor dust samples collected from homes in a Finnish rural-suburban (LUKAS2, N = 182) birth cohort, and the results were replicated in a German urban (LISA, N = 284) birth cohort. Human associated bacteria variable was created by summing up the relative abundances of five bacterial taxa. Bacterial richness, Shannon index and the relative abundances of seven bacterial genera, mostly within the phyla Proteobacteria and Firmicutes, were significantly higher in the dog than in the non-dog homes, whereas the relative abundance of human associated bacteria was lower. The results were largely replicated in LISA. Fungal microbiota richness and abundance of Leucosporidiella genus were higher in dog homes in LUKAS2 and the latter association replicated in LISA. Our study confirms that dog ownership is reproducibly associated with increased bacterial richness and diversity in house dust and identifies specific dog ownership-associated genera. Dogs appeared to have more limited influence on the fungal than bacterial indoor microbiota.

Eosinophil activity in infants hospitalized for wheezing and risk of persistent childhood asthma.

Eosinophilic inflammation has a central role in the pathogenesis of asthma. We aimed to elucidate whether elevated blood eosinophil count (B-EOS), eosinophil cationic protein in serum (S-ECP) or in nasopharyngeal aspirate (NPA-ECP) predict later asthma after hospitalization for wheezing in infancy. In 1992-1993, 100 infants aged <24 months were hospitalized for wheezing associated with respiratory infection. B-EOS, S-ECP and NPA-ECP were measured on admission. Asthma status was evaluated at the follow-up visits at the median ages of 4.0, 7.2 and 12.3 yr. Twenty (25%) of 81 children had asthma at all three visits and were considered to have persistent childhood asthma (PCA). Children with B-EOS >or= 0.450 x 10(9) cells/l had a 2.9-fold PCA risk compared with other children. The risk was 6.1-fold when S-ECP was >or=20.0 microg/l and 6.7-fold when NPA-ECP was >or=815.0 ng/g. By these cut-off limits, all these markers were specific (75-93%), but not very sensitive (30-58%) in predicting PCA. At least one marker was elevated in 75% of the children with PCA. The respective figure for NPA-ECP alone was 58%. In adjusted analyses, only elevated NPA-ECP was an independent risk factor for PCA (OR 4.09). In conclusion, eosinophil activity in early life predicts the development of childhood asthma after hospitalization for wheezing in infancy. The results highlight NPA-ECP as an independent predictor of the persistence of asthma at school age.

Rhinovirus Type in Severe Bronchiolitis and the Development of Asthma.

BACKGROUND: Respiratory syncytial virus (RSV)- and rhinovirus (RV)-induced bronchiolitis are associated with an increased risk of asthma, but more detailed information is needed on virus types. OBJECTIVE: To study whether RSV or RV types are differentially associated with the future use of asthma control medication. METHODS: Over 2 consecutive winter seasons (2008-2010), we enrolled 408 children hospitalized for bronchiolitis at age less than 24 months into a prospective, 3-center, 4-year follow-up study in Finland. Virus detection was performed by real-time reverse transcription PCR from nasal wash samples. Four years later, we examined current use of asthma control medication. RESULTS: A total of 349 (86%) children completed the 4-year follow-up. At study entry, the median age was 7.5 months, and 42% had RSV, 29% RV, 2% both RSV and RV, and 27% non-RSV/-RV etiology. The children with RV-A (adjusted hazard ratio, 2.3; P = .01), RV-C (adjusted hazard ratio, 3.5; P < .001), and non-RSV/-RV (adjusted hazard ratio, 2.0; P = .004) bronchiolitis started the asthma control medication earlier than did children with RSV bronchiolitis. Four years later, 27% of patients used asthma control medication; both RV-A (adjusted odds ratio, 3.0; P = .03) and RV-C (adjusted odds ratio, 3.7; P < .001) etiology were associated with the current use of asthma medication. The highest risk was found among patients with RV-C, atopic dermatitis, and fever (adjusted odds ratio, 5.0; P = .03). CONCLUSIONS: Severe bronchiolitis caused by RV-A and RV-C was associated with earlier initiation and prolonged use of asthma control medication. The risk was especially high when bronchiolitis was associated with RV-C, atopic dermatitis, and fever.

Early exposure and sensitization to cat and dog: different effects on asthma risk after wheezing in infancy.

Birth cohort studies have suggested that early exposure to furred pets protects from later asthma and allergy. The aim of the present study was to evaluate the association between exposure or sensitization to cat or dog in infancy, and later asthma and allergy assessed at the median ages of 4.0, 7.2 and 12.3 yr, in children who have wheezed at <24 months of age. Exposure to cat and dog in infancy was assessed by interviewing the parents. The child was considered as sensitized, if the allergen-specific IgE to cat or to dog was >or=0.35 kU/l, or if there was a positive skin test response. When the 20 children with persistent childhood asthma (doctor-diagnosed asthma at all three control visits) were compared with the other 61 children, an early exposure to dog (OR = 0.14, p = 0.034)) decreased the asthma risk and an early sensitization to cat (OR = 5.92, p = 0.008) and dog (OR = 9.33, p = 0.001) increased the asthma risk. There were less cat and dog keeping in atopic families and the effect of sensitization was, but the effect of exposure was not, robust to adjustments in multivariate analyses. The present study demonstrates, in a long-term follow-up after early wheezing, that early sensitization to cat and dog increases the risk of later asthma but early exposure to cat or dog has no such effect. Dog keeping was less frequent in atopic families, which may explain that the protective effect of early exposure to dog was lost in multivariate analyses.

Genome-Wide Association Study of Polymorphisms Predisposing to Bronchiolitis.

Bronchiolitis is a major cause of hospitalization among infants. Severe bronchiolitis is associated with later asthma, suggesting a common genetic predisposition. Genetic background of bronchiolitis is not well characterized. To identify polymorphisms associated with bronchiolitis, we conducted a genome-wide association study (GWAS) in which 5,300,000 single nucleotide polymorphisms (SNPs) were tested for association in a Finnish-Swedish population of 217 children hospitalized for bronchiolitis and 778 controls. The most promising SNPs (n = 77) were genotyped in a Dutch replication population of 416 cases and 432 controls. Finally, we used a set of 202 Finnish bronchiolitis cases to further investigate candidate SNPs. We did not detect genome-wide significant associations, but several suggestive association signals (p < 10-5) were observed in the GWAS. In the replication population, three SNPs were nominally associated (p < 0.05). Of them, rs269094 was an expression quantitative trait locus (eQTL) for KCND3, previously shown to be associated with occupational asthma. In the additional set of Finnish cases, the association for another SNP (rs9591920) within a noncoding RNA locus was further strengthened. Our results provide a first genome-wide examination of the genetics underlying bronchiolitis. These preliminary findings require further validation in a larger sample size.

Absence of Bordetella pertussis Among Infants Hospitalized for Bronchiolitis in Finland, 2008-2010.

In 169 Finnish infants hospitalized for bronchiolitis at age <6 months in 2008-2010, nasopharyngeal aspirates were tested by polymerase chain reaction for Bordetella pertussis and 16 viruses. Respiratory viruses were detected in 89% (71% with respiratory syncytial virus), but no infant had B. pertussis. The latter finding may reflect a positive effect from the broadening of the Finnish pertussis vaccination program in 2005.