The prevalence of childhood asthma in China: a systematic review

Asthma prevalence based on the Baidu index and China's Health Statistical Yearbook from 2011 to 2020 in China

Background

Due to environmental pollution, changes in lifestyle, and advancements in diagnostic technology, the prevalence of asthma has been increasing over the years. Although China has made early efforts in asthma epidemiology and prevention, there is still a lack of unified and comprehensive epidemiological research within the country. The objective of the study is to determine the nationwide prevalence distribution of asthma using the Baidu Index and China's Health Statistical Yearbook.

Methods

Based on China's Health Statistical Yearbook, we analyzed the gender and age distribution of asthma in China from 2011 to 2020, as well as the length of hospitalization and associated costs. By utilizing the Baidu Index and setting the covering all 31 provinces and autonomous regions in China, we obtained the Baidu Index for the keyword 'asthma'. Heatmaps and growth ratios described the prevalence and growth of asthma in mainland China.

Results

The average expenditure for discharged asthma (standard deviation) patients was ¥5,870 (808). The average length of stay (standard deviation) was 7.9 (0.38) days. During the period of 2011 to 2020, hospitalization expenses for asthma increased while the length of hospital stay decreased. The proportion of discharged patients who were children under the age of 5 were 25.3% (2011), 19.4% (2012), 16% (2013), 17.9% (2014), 13.9% (2015), 11.3% (2016), 10.2% (2017), 9.4% (2018), 8.1% (2019), and 7.2% (2020), respectively. The prevalence of asthma among boys was higher than girls before the age of 14. In contrast, the proportion of women with asthma was larger than men after the age of 14. During the period from 2011 to 2020, the median [The first quartile (Q1)-the third quartile (Q3)] daily asthma Baidu index in Guangdong, Beijing, Jiangsu, Sichuan, and Zhejiang were 419 (279-476), 328 (258-376), 315 (227-365), 272 (166-313), and 312 (233-362) respectively. Coastal regions showed higher levels of attention toward asthma, indicating a higher incidence rate. Since 2014, there has been a rapid increase in the level of attention toward asthma, with the provinces of Qinghai, Sichuan, and Guangdong experiencing the fastest growth.

Conclusion

There are regional variations in the prevalence of asthma among different provinces in China, and the overall prevalence of asthma is increasing.

Maternal exposure to PM2.5/BC during pregnancy predisposes children to allergic rhinitis which varies by regions and exclusive breastfeeding

BACKGROUND

Increasing prevalence of childhood allergic rhinitis(AR) needs a deeper understanding on the potential adverse effects of early life exposure to air pollution.

OBJECTIVES

The main aim was to evaluate the effects of maternal exposure to PM_2.5 and chemical constituents during pregnancy on preschool children's AR, and further to explore the modification effects of regions and exclusive breastfeeding.

METHODS

A multi-center population-based study was performed in 6 cities from 3 regions of China in 2011-2012. Maternal exposure to ambient PM_2.5 and main chemical constituents(BC, OM, SO₄^2-, NO₃^-, NH₄⁺) during pregnancy was assessed and a longitudinal prospective analysis was applied on preschool children's AR. The modification effects of regions and exclusive breastfeeding were investigated.

RESULTS

A total of 8.8% and 9.8% of children reported doctor-diagnosed allergic rhinitis(DDAR) and current hay fever, respectively, and 48.6% had less than 6 months of exclusive breastfeeding. The means of PM_2.5 during pregnancy were 52.7 μg/m³, 70.3 μg/m³ and 76.4 μg/m³ in the east, north and central south of China, respectively. Multilevel log-binomial model regression showed that each interquartile range(IQR) increase of PM_2.5 during pregnancy was associated with an average increase in prevalence ratio (PR) of DDAR by 1.43(95% confidence interval(CI): 1.11, 1.84) and current hay fever by 1.79(95% CI: 1.26, 2.55), respectively. Among chemical constituents, black carbon (BC) had the strongest associations. Across 3 regions, the eastern cities had the highest associations, followed by those in the central south and the north. For those equal to or longer than 6 months of exclusive breastfeeding, the associations were significantly reduced.

CONCLUSIONS

Children in east of China had the highest risks of developing AR per unit increase of maternal exposure to PM_2.5 during pregnancy, especially BC constituent. Remarkable decline was found in association with an increase in breastfeeding for ≥6 months, in particular in east of China.

Will Smog Cause Mental Health Problems? Indication from a Microsurvey of 35 Major Cities in China

Using the survey data of 21,861 participants from 35 major cities in China in 2018 and 2019, the effect of air quality on participants’ mental health was empirically tested based on the ordered probit model. The results showed that smog can significantly influence the mental health of participants. The better the air quality, the better the participants’ mental health, while poor air quality results in poor mental health. The older and higher-paid participants demonstrated poorer mental health. Additionally, for different health conditions, the air quality had different effects on the participants’ mental health. The healthier the participants, the more sensitive their mental health to changes in air pollution; the poorer the physical condition of the participants, the less sensitive their mental health to changes in air quality. Therefore, we need to more comprehensively and scientifically understand the effect of air quality on health. We need to pay attention not only to the adverse effects of smog on participants’ physical health, but also to its effects on participants’ mental health to improve both the physical and mental health of participants by improving the air quality.

Household mold exposure interacts with inflammation-related genetic variants on childhood asthma: a case-control study

BACKGROUND

A number of studies have examined the association between mold exposure and childhood asthma. However, the conclusions were inconsistent, which might be partly attributable to the lack of consideration of gene function, especially the key genes affecting the pathogenesis of childhood asthma. Research on the interactions between genes and mold exposure on childhood asthma is still very limited. We therefore examined whether there is an interaction between inflammation-related genes and mold exposure on childhood asthma.

METHODS

A case-control study with 645 asthmatic children and 910 non-asthmatic children aged 3-12 years old was conducted. Eight single nucleotide polymorphisms (SNPs) in inflammation-related genes were genotyped using MassARRAY assay. Mold exposure was defined as self-reported visible mold on the walls. Associations between visible mold exposure, SNPs and childhood asthma were evaluated using logistic regression models. In addition, crossover analyses were used to estimate the gene-environment interactions on childhood asthma on an additive scale.

RESULTS

After excluding children without information on visible mold exposure or SNPs, 608 asthmatic and 839 non-asthmatic children were included in the analyses. Visible mold exposure was reported in 151 asthmatic (24.8%) and 119 non-asthmatic children (14.2%) (aOR 2.19, 95% CI 1.62-2.97). The rs7216389 SNP in gasdermin B gene (GSDMB) increased the risk of childhood asthma with each C to T substitution in a dose-dependent pattern (additive model, aOR 1.32, 95% CI 1.11-1.57). Children carrying the rs7216389 T allele and exposed to visible mold dramatically increased the risk of childhood asthma (aOR 3.21; 95% CI 1.77-5.99). The attributable proportion due to the interaction (AP: 0.47, 95% CI 0.03-0.90) and the relative excess risk due to the interaction (RERI: 1.49, 95% CI 0-2.99) were statistically significant.

CONCLUSIONS

In the present study, there was a significant additive interaction between visible mold exposure and rs7216389 SNP on childhood asthma. Future studies need to consider the gene-environment interactions when exploring the risk factors of childhood asthma.

The cost-effectiveness of low-dose budesonide as a Step 2 treatment for pediatric asthma in China

Aim: To compare the cost-effectiveness of low-dose budesonide versus montelukast among patients aged 1-5 years from a Chinese patient and healthcare payer perspective. Materials & methods: A Markov model based on exacerbation states was developed. Exacerbation was defined as the need for rescue therapy (mild exacerbation) or hoscopitalization (moderate-to-severe exacerbation). Inputs including efficacy (i.e., exacerbation rates), mortality, utilities, costs and treatment adherence were obtained from literature. Results: Compared with montelukast, low-dose budesonide led to fewer exacerbation events (1.44 vs 2.15), lower costs (¥3675 vs 4130) and slightly more quality-adjusted life years (0.974 vs 0.967) over 1 year. Conclusion: These findings may improve the use of low-dose budesonide, an economically and clinically preferable treatment to montelukast in pediatric patients.

The disease burden of childhood asthma in China: a systematic review and meta-analysis

Background

In China, childhood asthma prevalence showed a remarkable increase in the past decades. An updated epidemiological assessment of childhood asthma in China with a focus on prevalence and time trends is required.

Methods

We systematically searched three main Chinese databases and one English database to identify epidemiological studies of the prevalence of childhood asthma in China. Asthma cases were defined according to one of the five sets of Chinese diagnostic criteria which were established by the Children Respiratory Disease Group. We estimated age- and sex-specific prevalence of asthma using a multilevel mixed-effects logistic regression. We presented the time trends of asthma prevalence between 1990 and 2020 by age, sex and setting (urban vs rural), and also estimated the number of children affected by asthma in 2010.

Results

In 1990, the prevalence of asthma ranged from 0.13% (95% confidence interval (CI) = 0.10-0.20) in rural girls aged 14 years to 1.34% (95% CI = 1.11-1.67) in urban boys aged five years. In 2010, the overall prevalence of asthma in Chinese children aged 0-14 years was 2.12% (95% CI = 1.83-2.51), corresponding to 5.16 million children living with asthma. Children aged 5-9 years were with the highest prevalence estimate of 2.65% (95% CI = 2.31-3.12) and those aged 10-14 years were with the lowest (1.48%, 95% CI = 1.26-1.78). In 2020, it is expected that this disparity will continue, with the prevalence of asthma being at the lowest level among rural girls aged 14 years (1.11%, 95% CI = 0.82-1.54) and at the highest level among urban boys aged four years (10.27%, 95% CI = 8.61-12.18). Over the 30 years (1990-2020), the prevalence of asthma in children aged 0-14 years has increased in both sexes and settings, which was consistently the lowest in rural girls and the highest in urban boys.

Conclusions

This study shows that childhood asthma has been increasingly prevalent in China. Asthma is more frequent in boys and in rural areas. The detailed and systematic estimates of asthma prevalence in this study constitute the best currently available basis for policymaking, planning, and allocation of health and welfare resources related to the burden of childhood asthma in China.

Effects of childhood exposure to PM2.5 in a Memphis pediatric asthma cohort

The effects of childhood exposure to ambient air pollution and their influences on healthcare utilization and respiratory outcomes in Memphis pediatric asthma cohort are still unknown. This study seeks to (1) investigate individual-level associations between asthma and exposure measures in high asthma rate and low asthma rate areas and (2) determine factors that influence asthma at first year of a child's life, first 2 years, first 5 years, and during their childhood. Datasets include physician-diagnosed asthma patients, on-road and individual PM_2.5 emissions, and high-resolution spatiotemporal PM_2.5 estimates. Spatial analytical and logistic regression models were used to analyze the effects of childhood exposure on outcomes. Increased risk was associated with African American (AA) (odds ratio (OR) = 3.09, 95% confidence interval (CI) 2.80-3.41), aged < 5 years old (OR = 1.31, 95% 1.17-1.47), public insurance (OR = 2.80, 95% CI 2.60-3.01), a 2.5-km radius from on-road emission sources (OR = 3.06, 95% CI 2.84-3.30), and a 400-m radius from individual PM_2.5 sources (OR = 1.33, 95% CI 1.25-1.41) among the cohort with residence in high asthma rate areas compared to low asthma rates areas. A significant interaction was observed between race and insurance with the odds of AA being approximately five times (OR = 4.68, 95% CI 2.23-9.85), public insurance being about three times (OR = 2.65, 95% CI 1.68-4.17), and children in their first 5 years of life have more hospital visits than other age groups. Findings from this study can guide efforts to minimize emissions, manage risk, and design interventions to reduce disease burden.

Effects of Diatomaceous Earth on House Dust Mite Sensitization in BALB/c Mice

BACKGROUND

House Dust Mite (HDM) is associated with hypersensitivity such as asthma. Patients with asthma benefit from improved living environment by reducing HDM exposure. In this study, we examined the effects of commercialized diatomaceous earth product, Casaggia® used as construction materials, on hypersensitivity in HDM-sensitized mice.

METHODS

Male mice were sensitized with house dust mite extract for 7d and then housed in diatomaceous earth (DE)-coated cages for 14 days at Animal Center of the Taichung Veterans General Hospital, Taichung, Taiwan in 2014. Levels of cytokine were determined using ELISA. White blood cell counts were recorded over 21d. Histological analysis was conducted to determine the remodeling of respiratory tract.

RESULTS

Exposure to DE resulted in a suppression in elevated eosinophilia induced by HDM in mice. In addition, elevated serum IgE responding to HDM sensitization were restored in the presence of DE. DE ameliorated the inflammation progression in airway.

CONCLUSION

Environmental exposure to DE is suggested to benefit patients with hypersensitivity through relieving inflammatory symptoms. In a sense of prevention, DE represents a potential material against development of asthma.

Household dampness-related exposures in relation to childhood asthma and rhinitis in China: A multicentre observational study

During 2010-2012, we conducted an observational study on household environment and health outcomes among 40,010 preschool children from seven cities of China. Here we examined associations of six dampness-related indicators (visible mold spots, visible damp stains, damp clothing and/or bedding, water damage, condensation on windowpane, moldy odor) in the current residence and three dampness-related indicators (visible mold spots, condensation on windowpane, moldy odor) in the early residence with childhood asthma and rhinitis. In the multi-level logistic regression analyses, visible mold spots and visible damp stains in the current residence were significantly associated with the increased odds of doctor-diagnosed asthma and allergic rhinitis during lifetime-ever (adjusted odd ratios (AORs) range: 1.18-1.35). All dampness-related indicators were significantly associated with increased odds of wheeze and rhinitis during lifetime-ever and in the past 12 months (AORs range: 1.16-2.64). The cumulative numbers of damp indicators had positively dose-response relationships with the increased odds of the studied diseases. These associations for wheeze and rhinitis were similar between northern children and southern children. Similar results were found in the sensitive analyses among children without a family history of allergies and among children without asthma and allergic rhinitis. For 3-6 years-old children in mainland of China in 2011, we speculated that about 90,000 (2.02%) children with asthma and about 59,000 (1.09%) children with allergic rhinitis could be attributable to exposing to visible mold spots in the current residence. Our results suggested that early and lifetime exposures to household dampness indicators are risk factors for childhood asthma and rhinitis.

Exercise training as an adjunctive therapy to montelukast in children with mild asthma: A randomized controlled trial

BACKGROUND

This study investigated the effectiveness and safety of exercise training (ET) as an adjunctive therapy to montelukast for children with mild asthma (MA).

METHODS

A total of 72 children, ages 4 to 12 years with MA were randomly assigned to a treatment group or a control group at a ratio of 1:1. The subjects in the treatment group received ET plus montelukast, while the participants in the control group received montelukast alone. The primary endpoint was lung function, as measured by forced expiratory volume in 1 second (FEV1) and ratio between FEV1 and forced vital capacity (FEV1/FVC). The secondary endpoints included the symptom improvements, as measured by clinical assessment score, and quality of life (QoL), as assessed with Paediatric Allergic Disease Quality of Life Questionnaire (PADQLQ) scores. In addition, adverse events were also assessed during the period of this study. All outcomes were measured at baseline, at the end of 6-week treatment and 2-week follow-up after the treatment.

RESULTS

After 6-week treatment and 2-week follow-up, although ET plus montelukast did not show better effectiveness in improving lung function, as evaluated by the FEV1 (P > .05) and FEV1/FVC (P > .05) than montelukast alone, significant relief in clinical symptoms (P < .01), and improvement in QoL (P < .01) have achieved. Additionally, both groups had similar safety profile.

CONCLUSION

The results of this study showed that ET as an adjunctive therapy to montelukast may benefit for children with MA. Further studies are still needed to warrant the results of this study.

Urinary phthalate metabolites in relation to childhood asthmatic and allergic symptoms in Shanghai

BACKGROUND

Few studies can be found on phthalate exposure in relation to childhood asthma and allergic symptoms from Mainland China, where a persistent increase in prevalence of childhood asthma and allergic disease has been observed.

OBJECTIVES

This study aimed to assess the exposure levels to phthalates and its relationship with asthmatic and allergic symptoms among children in Shanghai, which has the highest prevalence of childhood asthma in Mainland China.

METHODS

A follow-up study (2013-2014) of 434 children aged 5-10 years was conducted, based on the China, Children, Homes, Health (CCHH) study (2011-2012) in Shanghai, China. Information on asthmatic and allergic symptoms (wheeze, rhinitis, and eczema) were collected using validated questionnaires. Ten phthalate metabolites in morning urine samples were analyzed by high-performance liquid chromatography with triple quadrupole tandem mass spectrometry (HPLC-MS/MS). Multivariable logistic regression was used to estimate the associations between symptoms and urinary phthalate metabolites controlling for demographics, family history of allergic diseases and other covariates.

RESULTS

Nine out of 10 phthalate metabolites were detected in all subjects (average detection rate of 93.2%). By multivariable logistic regression analyses, the 4th quartile of Mono‑n‑butyl phthalate (MnBP) (reference: 1st quartile) had adjusted prevalence odds ratios (aPOR_S) and 95% confidence intervals (95%CIs) of 2.27(1.06-4.88), 2.14(1.02-4.46) and 2.98(1.19-7.50) for wheeze, rhinitis and eczema, respectively, while those of Mono‑isobutyl phthalate (MiBP) were 2.23(1.08-4.62) and 2.96(1.02-8.60) for rhinitis and eczema, respectively. The highest quartile of mono‑2‑ethyl‑5‑hydroxyhexyl phthalate(MEHHP) and mono‑2‑ethyl‑5‑oxohexyl phthalate(MEOHP) had aPOR_S and 95%CIs of 3.10(1.10-8.74) and 2.63(1.02-6.80) for eczema, respectively. By summing up the 4 low molecular weight metabolites (∑₄LMWP) and all 9 metabolites (∑₉Total), the highest quartiles of ∑₄LMWP and∑₉Total were significantly associated with all symptoms. In most of the above associations, a significantly increasing trend from the 1st to the 4th quartile was observed. Subjects with 2 or 3 concomitant symptoms (reference: no symptoms) had significant positive associations with a higher level (the 4th quartile) of phthalate metabolites.

CONCLUSIONS

Low MW metabolites such as MnBP and MiBP, high MW DEHP and the total amount of phthalate metabolites might have adverse health effects on asthma and allergic symptoms in Chinese children.

Soil is a key factor influencing gut microbiota and its effect is comparable to that exerted by diet for mice

Exposure to an unsanitary environment increases the diversity and alters the composition of gut microbiota. To identify the key element in the unsanitary environment responsible for this phenomenon, we investigated the effect and the extent by which the soil in our environment influenced the composition of gut microbiota. Results show that adding unsterile or sterile soil to bedding, either before birth or after weaning, influences significantly the composition of mice gut microbiota. Specifically, unsterile soil increases the richness and biodiversity of gut microbiota. Interestingly, based on UniFrac distance analysis of 16S rRNA sequences, the impact of soil on gut microbiota is comparable to that exerted by diet. These findings provide a potential new strategy for intervening on the human gut microbial community and preventing disease.

Association Between TGF-β1 Polymorphisms and Asthma Susceptibility Among the Chinese: A Meta-Analysis

OBJECTIVE

Asthma is the most common chronic pulmonary disease in China and is characterized by airway inflammation and episodic airflow obstruction. The aim of this meta-analysis was to evaluate the relation of two transforming growth factor-β1 (TGF-β1) polymorphisms with asthma risk in Chinese population.

METHODS

PubMed, Springer, EMBASE, MEDLINE, CNKI (China National Knowledge Infrastructure), and Wanfang databases were used to search and retrieve relevant eligible case-control studies published through December 2017. The odds ratios (OR) and 95% confidence intervals (CI) were used to evaluate the effect.

RESULTS

A total of 2040 asthma patients and 1952 controls from 12 studies were analyzed. Two polymorphic sites of TGF-β1 gene were identified: -509C/T and +869T/C. We found that the -509C/T polymorphism was associated with increased asthma risk under the heterozygous model (CT vs. CC: OR = 1.40, 95% CI = 1.03-1.90, p = 0.03) and the dominant model (TT+CT vs. CC: OR = 1.41, 95% CI = 1.05-1.90, p = 0.02). Subgroup analyses by age suggested that -509C/T variant was associated with childhood asthma. Analysis of disease severity indicated that this variant was associated with both mild-to-moderate asthma and severe asthma. However, the +869T/C polymorphism was not associated with asthma susceptibility in subgroup analysis by age or disease severity.

CONCLUSIONS

This study demonstrated that the -509C/T polymorphism of the TGF-β1 gene might be a risk factor for asthma in the Chinese population, especially in Chinese children. Further large-scale case-control studies are still required.

Time Trends and Regional Variation in Prevalence of Asthma and Associated Factors in Saudi Arabia: A Systematic Review and Meta-Analysis

BACKGROUND

Asthma is the most common reason for emergency visits to hospital and loss of productive hours. In Saudi Arabia, asthma affects more than 2 million people and majority of them have uncontrolled asthma with their quality of life adversely being impacted. It is well known that the prevalence of asthma has been increasing in many places around the world in the last few decades. The present review attempted to identify studies on asthma and associated factors in Saudi Arabian population and assess their time trends and regional variation.

METHODS

The titles and abstracts of retrieved articles were compared to delete duplication and irrelevant data. A data collection form was designed to extract several key components from selected articles like bibliographic information on the article, study population, and sample size. Extracted information was grouped appropriately for data analysis. Database search retrieved 71 articles. Applying inclusion and exclusion criteria, 40 articles were excluded and 31 qualified full articles were included for the review.

RESULTS

Among 31 retained studies, Riyadh had the highest publication output followed by Jeddah. Ten studies were based on ISAAC and 5 on non-ISAAC questionnaires while 5 studies were genetic studies conducted to unravel the genetic basis of asthma. Most of the studies were conducted on pediatric subjects of less than 16 years of age. Sample sizes ranged from less than 150 to more than 10000 with study settings being predominantly urban (22 studies). The pooled weighted prevalence rates of asthma, lifetime wheeze, and rhinitis were 14.3% (95% CI: 13.4-15.2), 16.5 (95% CI 15.5-17.4), and 21.4 (95% CI 20.5-22.3), respectively. An increase in asthma prevalence from 1990 to 2000 along with a stabilized or not so significant decline in the prevalence from 2010 to 2016 was observed.

CONCLUSION

The prevalence of asthma varied in different regions without any disparity in prevalence in the rural and urban areas of Saudi Arabia. The understanding of genetic variability and recognition of risk factors in asthma patients can greatly help in individualizing the therapy for the management and control of asthma.

Epidemiology of childhood asthma in mainland China (1988-2014): A meta-analysis

BACKGROUND

After the promotion of the two-child policy in recent years, the population of children in mainland China was bound to have a rapid growth, which would bring great challenges to public health. A number of cross-sectional studies on the epidemic of childhood asthma in mainland China were recently conducted, and varied prevalences were reported. Thus, knowing the epidemiology of childhood asthma in mainland China is of great necessity.

OBJECTIVE

Our study aimed to summarize the pooled prevalence of childhood asthma in mainland China and its time trend, gender difference, regional distribution, and age structure.

METHODS

Studies that reported the prevalence of childhood asthma in mainland China were identified via a systematic data base search through July 1, 2016. Meta-analysis was used to estimate the prevalence of childhood asthma and its subgroups, including gender, age groups, years, and regions. The regional distribution of the prevalence was set by province with the help of a geographic mapping software. The autoregressive integrated moving average model was used to predict the current prevalence of asthma.

RESULTS

A total of 117 studies published from 1988 to 2014 in mainland China with a total sample size of 2,678,696 were included. The overall current prevalence and lifetime prevalence of childhood asthma was 2.112% (95% confidence interval [CI], 1.977-2.247%) and 2.502% (95% CI, 2.166-2.838%), respectively. The difference of the prevalences between male and female patients was significant: odds ratio 1.54 (95% CI, 1.47-1.62) for the current prevalence and odds ratio 1.61 (95% CI, 1.47-1.77) for the lifetime prevalence.

CONCLUSION

The prevalence of childhood asthma in mainland China was low but has been increasing remarkably since 1998. Boys are more likely to have asthma throughout most of their childhood. Preschoolers (3-6 years old) showed a higher prevalence than the other age groups. The current prevalence of childhood asthma probably increased slightly from 2017 to 2019.

The safety profile of subcutaneous allergen immunotherapy in children with asthma in Hangzhou, East China

BACKGROUND

The aim of the current study is to evaluate the prevalence, severity and possible risk factors of systemic reactions (SRs) to subcutaneous allergen immunotherapy (SCIT) in children and adolescents with asthma in Hangzhou, east China's Zhejiang province.

METHODS

From January 2011 to December 2016, this survey analysed the SCIT-related SRs involving 429 patients (265 children and 134 adolescents) affected by allergic asthma. Recorded data included demographics, diagnosis, patient statuses, pulmonary function testing results before and after each injection, allergen dosage, and details of SRs.

RESULTS

All patients finished the initial phase and six patients withdrew during the maintenance phase. There were 2.59% (328/12,655) SRs in all injections (3.28% in children and 1.47% in adolescents); 15.62% (67/429) patients experienced SRs (18.49% children and 10.98% adolescents). There were 54.57% SRs of grade 1; 42.37% SRs of grade 2; 3.05% SRs of grade 3; and no grades 4 or grade 5 SRs occurred in patients. Most reactions were mild, and were readily controlled by immediate emergency treatment. There was no need for hospitalisation. The occurrence of SRs was significantly higher in children than that in adolescents (p<0.01). A higher ratio of SRs was found among patients with moderate asthma.

CONCLUSION

This retrospective survey showed that properly-conducted SCIT was a safe treatment for children and adolescents with asthma in Hangzhou, East China. Children and patients with moderate asthma may be prone to develop SRs.

Prenatal exposure to bisphenol A and risk of allergic diseases in early life

BACKGROUND

Prenatal exposure to bisphenol A (BPA) affects immune system and promotes allergy and asthma in mice, but findings in human studies are limited. We investigated whether prenatal exposure to BPA is associated with increased risk of allergic diseases in infants.

METHODS

We measured BPA concentrations in maternal urine samples collected at delivery from 412 women in Wuhan, China. The occurrence of allergic diseases including eczema and wheeze were assessed at age 6 mo through questionnaires. We used logistic regression to evaluate the association between urinary BPA levels and the risk of allergic diseases.

RESULTS

Mothers of infants with allergic diseases had significantly higher urinary BPA levels than those of infants without allergic diseases (median: 2.35 vs. 4.55 µg/l, P = 0.03). Increased risk of infant allergic diseases was associated with creatinine-adjusted maternal urinary BPA concentrations. And this association was limited to females (odds ratio (OR) = 1.36; 95% confidence interval (CI): 1.10-1.79) rather than males. After stratification by maternal age, the association was only significant in infants of mothers who were younger than 25 y old (OR = 1.90; 95% CI: 1.09-3.29).

CONCLUSION

Prenatal exposure to BPA may potentially increase the risk of allergic diseases at very early life in female infants.

Predictive value of IL-35 and IL-17 in diagnosis of childhood asthma

This study aimed to evaluate the correlation between serum levels of IL-17 and IL-35 and the presence and severity of childhood asthma. The study was performed on 60 diagnosed asthmatic children, who were further classified into four groups according to the Global Initiative for Asthma Guidelines for Asthma Severity and Control (GINA) 2016, plus 30 age- and sex-matched apparently healthy children. All participants were subjected to full medical history, clinical examination, pulmonary function tests and laboratory evaluation in the form of complete blood count (CBC), serum total IgE, IL-17 and IL-35 by ELISA. Our results revealed that eosinophils count, IgE and IL-17 were significantly higher in the asthmatic group than the control group (p < .001), while IL-35 levels were significantly lower in asthmatics than control (p < .001). A strong negative correlation was found between serum IL-17 and serum IL-35; a positive correlation was found between serum IL-17 and both of serum total IgE and eosinophils counts in atopic asthmatic patients, and serum IL-35 showed significant negative correlations with both. ROC analysis of the data showed that the cut-off value of IL-35 level was <189.5 pg/mL and for IL-17 level, it was >13.1 pg/mL; this value could predict childhood asthma with sensitivity of 81.7% and 83.3%, and specificity of 76.7% and 70%, respectively. A combination of both cytokines yielded an increase in sensitivity to 95%. In conclusion, in the current study, IL-17 is upregulated while IL-35 is downregulated in childhood asthma with a significant negative correlation between both. These results suggest that both may play an important role in the pathogenesis of childhood asthma.

Mindfulness and asthma symptoms: A study among college students

INTRODUCTION

Given the known link between asthma and stress as well as the link between mindfulness and stress, we explore the possible association between trait mindfulness and asthma-related diagnosis and symptoms with a cross-sectional study.

METHOD

In 2014, we surveyed a sample of college students in their freshman year, from a public university in Shanghai, China. We used three multilevel logistic regressions to estimate the association between trait mindfulness (measured by Mindful Awareness Attention Scale, MAAS) and self-report of ever having an asthma diagnosis, ever having had persistent dry cough, and ever having had wheezing symptoms. Age, gender, household registration status, and the frequency of smog in the respondent's hometown were used as control variables in the study. The home province of the student was used as the cluster variable in the multilevel models.

RESULTS

Among the 1392 students in the analysis sample (mean age = 18.3), 47 (3.4%) self-reported an asthma diagnosis, 251 (18.1%) reported having had persistent dry cough, and 100 (7.2%) reported having had wheezing symptoms. A one-unit increase in MAAS is negatively associated with having a self-reported asthma diagnosis (Odds Ratio (OR): 0.662, 95% Confidence Interval (CI): 0.452, 0.969, p = 0.034), having had persistent dry cough (OR: 0.658, 95% CI: 0.545, 0.795, p < 0.001), and wheezing (OR = 0.747, 95% CI: 0.569, 0.981, p = 0.036).

DISCUSSION

This is the first study to suggest a link between trait mindfulness and asthma. Our finding provides evidence that people with higher level of mindfulness are less likely to have had an asthma diagnosis and less likely to have the symptoms of persistent dry cough and wheezing.

Hospitalizações de crianças por condições evitáveis no Estado do Paraná: causas e tendência

Resumo Objetivo Analisar a tendência das hospitalizações por condições sensíveis à atenção primária, segundo principais causas em menores de cinco anos. Métodos Estudo de séries temporais do tipo ecológico realizado com dados do Sistema de Informação Hospitalar do Estado do Paraná. A análise ocorreu a partir das taxas de hospitalização e de modelos de regressão polinomial segundo idade e causa. Resultados As causas mais frequentes foram pneumonias, gastrenterites, asma, infeção no rim e trato urinário e deficiências nutricionais. As hospitalizações por pneumonia, asma e deficiências nutricionais em menores de cinco anos reduziram e por gastroenterites mantiveram-se estáveis. Houve aumento nas taxas de hospitalização por infecção no rim e trato urinário em todas as idades. Conclusão A tendência de hospitalização por condições sensíveis em menores de cinco anos foi crescente apenas para as crianças menores de um ano. As hospitalizações por pneumonias, gastroenterites, asma e deficiências nutricionais apresentaram tendência decrescente.

Protective effect of Bifidobacterium infantis CGMCC313-2 on ovalbumin-induced airway asthma and β-lactoglobulin-induced intestinal food allergy mouse models

AIM

To determine whether oral administration of Bifidobacterium infantis CGMCC313-2 (B. infantis CGMCC313-2) inhibits allergen-induced airway inflammation and food allergies in a mouse model.

METHODS

Ovalbumin (OVA)-induced allergic asthma and β-lactoglobulin-induced food allergy mouse models were used in this study. Following oral administration of B. infantis CGMCC313-2 during or after allergen sensitization, histopathologic changes in the lung and intestine were evaluated by hematoxylin and eosin (HE) staining. In the allergic asthma mouse model, we evaluated the proportion of lung-infiltrating inflammatory cells. OVA-specific IgE and IgG1 levels in serum and cytokine levels in bronchoalveolar lavage fluid (BALF) were also assessed. In the food allergy mouse model, the levels of total IgE and cytokines in serum were measured.

RESULTS

Oral administration of B. infantis CGMCC313-2 during or after allergen sensitization suppressed allergic inflammation in lung and intestinal tissues, while the proportion of infiltrating inflammatory cells was significantly decreased in the BALF of allergic asthma mice. Moreover, B. infantis CGMCC313-2 decreased the serum levels of total IgE in food allergy mice, and reductions in IgE and IgG1 were also observed in OVA-induced allergic asthma mice. The expression of interleukin-4 (IL-4) and IL-13 in both serum and BALF was suppressed following the administration of B. infantis CGMCC313-2, while an effect on serum IL-10 levels was not observed.

CONCLUSION

B. infantis CGMCC313-2 inhibits the secretion of allergen-induced IgE, IL-4 and IL-13, and attenuates allergic inflammation.

Multimorbidities of asthma, allergies, and airway illnesses in childhood: Chance or not chance?

OBJECTIVES

We investigated patterns of multimorbidities among asthma, allergies, and respiratory illnesses in preschool children. We investigated multimorbidities of lifetime asthma, allergic rhinitis, eczema, food allergy, pneumonia, and ear infections; and multimorbidities of current (in the last year before the survey) wheeze, dry cough, rhinitis, eczema, and common cold during childhood. We further analyzed whether prevalences of these multimorbidities were due to chance.

METHODS

A cross-sectional study was conducted in 72 kindergartens of Shanghai, China. Parents of preschool children were surveyed with a modified ISAAC questionnaire. Observed prevalences (OPs), expected prevalences (EPs), absolute excess comorbidities (AECs), and relative excess comorbidities (RECs) of various combinations of illnesses were calculated to indicate whether the combined illnesses were related.

RESULTS

We analyzed questionnaires for children aged 4-6 years, whose 13,335 questionnaires were the majority of the total 15,266 returned questionnaires (response rate: 85.3%). The studied illnesses were common. For children who had more than three lifetime or current illnesses, OPs tended to be higher than EPs. Most OPs and EPs were higher in boys than in girls, and were higher in children with a family history of atopy (FHA) than in children without FHA. AECs and RECs between boys and girls as well as between children with and without FHA were substantially different.

CONCLUSIONS

Our findings suggest that multimorbidities among childhood asthma, allergies, and respiratory illnesses are likely not random, but rather share etiology. Specific patterns of childhood asthma multimorbidities perhaps differ between boys and girls and between children with and without FHA.

Prevalence and Occupational and Environmental Risk Factors of Self-Reported Asthma: Evidence from a Cross-Sectional Survey in Seven Chinese Cities

OBJECTIVE

Asthma is one of the most common chronic diseases and associated with significant morbidity and mortality. However, few data on occupational and environmental risk factors of asthma are available, particularly in Asian adults. Based on a national cross-sectional survey, we assessed the prevalence and risk factors of asthma in Chinese adults.

METHODS

A total of 9974 participants aged 15 years and over in seven Chinese cities were selected using a stratified four-stage random sampling. All participants were interviewed face-to-face in their homes using a standardized self-administered questionnaire. Multivariate logistic regression analyses were adopted to determine various risk factors for asthma.

RESULTS

The prevalence of self-reported lifetime asthma was 2.46% among the entire adult population, 3.02% among males and 1.93% among females. The prevalence varied by age group, ethnicity, marital status, education, and floor space per person (p < 0.05). After adjusting for socio-demographic variables and smoking, we found independent occupational and environmental determinants of asthma, including a clearance-related job (OR = 2.28, 95%CI: 1.07-4.89), occupational exposure to industrial or occupational poisonous gas (OR = 4.21, 95%CI: 2.43-7.30), having large amounts of carpet in the workplace (OR = 2.61, 95%CI: 1.20-5.69) and using coal for cooking (OR = 2.65, 95%CI: 1.26-5.57).

CONCLUSIONS

Asthma is a serious public health problem in China. Our study provides important updated information on the prevalence of asthma and its associated risk factors, which may help us better understand the epidemiology of asthma and prevent this disorder.

Prevalence of asthma among Middle Eastern children: A systematic review

Background: The prevalence of asthma and allergy has increased during the last decades, especially in children. However, little is known about it in the Middle East region. This systematic review is aimed to estimate the prevalence of asthma among the Middle Eastern children.

Methods: Local and international scientific databases including SID, Iranmedex, Medline and Science Direct were systematically searched for relevant keywords including; asthma, prevalence, children, International Study of Asthma and Allergies in Childhood (ISACC) and the names of Middle Eastern countries for the period of 1996-2011. Papers in Persian and English which met the defined criteria were included into the study. Bibliographies of the extracted articles were also searched. After extraction of data, heterogeneity between studies and publication bias were measured using Egger's-test. Effect size was pooled by the random-effect model. Since significant heterogeneity was found between studies, univariate meta-regression analyses were done to assess the association of variables with the overall results.

Results: Fifty studies in the Middle East examined the prevalence of asthma and allergy in children under the age of 18 years according to the ISAAC criteria and were included. A total number of 289,717 children were examined in the included studies and the prevalence varied from 0.7 % in Isfahan to 22.3 % in Bagdad. The total prevalence of diagnosed asthma was calculated 7.53 % (95% Cl: 6.38-8.75). Prevalence of asthma in the 13-14 years age group was 7.57% (95% Cl: 5.78-9.29) and in 6-7 years age group was 7.43% (95% Cl: 5.75-9.10). The prevalence of asthma among girls, based on random effect model, was 6.30% (95% Cl: 4.97-7.61) and among boys, it was 8.91% (95% Cl: 6.80-11.04).

Conclusion: The prevalence of asthma in the Middle East is lower than most developed countries. However, there is not enough longitudinal data to estimate the trend over time. In order to have more accurate estimates and to provide evidence for proper planning, standard epidemiologic studies should be conducted in countries of the region.

Internal exposure levels of typical POPs and their associations with childhood asthma in Shanghai, China

Polybrominated diphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) are common persistent organic pollutants (POPs) that may be associated with childhood asthma. The concentrations of PBDEs, PCBs and OCPs were analyzed in pooled serum samples from both asthmatic and non-asthmatic children. The differences in the internal exposure levels between the case and control groups were tested (p value <0.0012). The associations between the internal exposure concentrations of the POPs and childhood asthma were estimated based on the odds ratios (ORs) calculated using logistic regression models. There were significant differences in three PBDEs, 26 PCBs and seven OCPs between the two groups, with significantly higher levels in the cases. The multiple logistic regression models demonstrated that the internal exposure concentrations of a number of the POPs (23 PCBs, p,p'-DDE and α-HCH) were positively associated with childhood asthma. Some synergistic effects were observed when the children were co-exposed to the chemicals. BDE-209 was positively associated with asthma aggravation. This study indicates the potential relationships between the internal exposure concentrations of particular POPs and the development of childhood asthma.

Special considerations--asthma in children

BACKGROUND

Asthma is among the most common chronic diseases of childhood. Management of pediatric asthma requires an understanding of the issues that uniquely effect children. This review provides the reader with the current state and future directions of pediatric asthma.

METHODS

Review of the pediatric asthma literature was undertaken with emphasis on randomized controlled trials and systematic reviews.

RESULTS

The prevalence of pediatric asthma remains elevated and is increasingly being appreciated in select global regions. Effective treatment in any setting begins with a focused medical history that queries key asthma features that inform both diagnostic and monitoring strategies. A thorough medical history may yield comorbid upper airway disorders and allergic triggers that could potentially exacerbate airway inflammation. Pre-bronchodilator and post-bronchodilator lung function testing is a preferable diagnostic strategy to quantitatively assess obstructive pulmonary disease among children capable of performing the testing maneuvers. Pediatric asthmatics who continue to have poor disease control require monitoring of medication adherence and drug delivery techniques, because both are often linked with disease outcomes. Therapeutic strategies in children are notably distinct from adults due to the possible effects of inhaled corticosteroids on reduced bone mineral density and growth. Adolescents may also require more time to address the psychosocial complexities that may complicate the required daily usage of asthma medicines.

CONCLUSION

Asthmatic children are distinct from their adult counterparts due to limitations inherent in the pediatric age group. A unified and evidence-based approach to pediatric asthma may improve clinical outcomes.

The link between mold sensitivity and asthma severity in a cohort of northern Chinese patients

BACKGROUND

Mold sensitivity in asthmatic patients has recently attracted clinical interest; however the links between mold sensitivity and asthma severity in the Chinese population have been poorly characterized. In this study, we assess the relationship between asthma severity and airborne mold sensitivity in a cohort of northern Chinese patients.

METHODS

Ninety-three non-smoking adult outpatients with asthma completed a questionnaire and underwent skin prick testing with five aeroallergens. For all patients, eosinophil cell counts, total serum IgE (sIgE) levels, and pulmonary function were measured. An asthma severity score was calculated based on the patient's forced expiratory volume in one second (FEV1), number of asthma attacks, number of hospital admissions, and use of inhaled or oral corticosteroids in the past year.

RESULTS

Ninety-three patients were divided into three groups based on the results of their allergy tests: negative results for all tested allergens (group A, n=32); positive reactions to aeroallergens including mold antigens (group B, n=41); and positive reactions to aeroallergens other than molds (group C, n=20). Patients in group B had a lower FEV1 (74.46%±23.09% predicted) compared with group A (85.52%±19.53%, P=0.023). Patients in both group B and C had elevated absolute eosinophil count (AEC) (group A: 3.12%±2.71%, group B: 5.41%±2.85%, group C: 6.1%±4.49%; group A vs. group B, P=0.008; group A vs. group C, P=0.002), and total sIgE values (group A: 117.36±144.90 IU/mL, group B: 195.86±155.87 IU/mL, group C: 253.31±152.41 IU/mL; group A vs. group B, P=0.031; group A vs. group C, P=0.002) compared with patients in group A. Asthma severity scores were higher in patients in group B compared to patients in group C (7 vs. 5.5, P<0.05). Patients allergic to molds were more likely to have severe asthma [odds ratio 3.636, 95% confidence interval (CI): 1.394 to 9.484; for severe versus mild asthma, P<0.05]. There was no association between asthma severity and sensitisation to house mites or weeds.

CONCLUSIONS

Mold sensitivity is positively correlated with asthma severity in our cohort of northern Chinese patients.

Efficacy evaluation of summer acupoint application treatment on asthma patients: a two-year follow-up clinical study

fill out a questionnaire evaluating asthma degree, exacerbation frequency, concomitant medications and self-satisfaction. The self-rate and doctor-report outcomes obtained in parallel were evaluated to assess the efficacy of SAAT.

RESULTS

A total of 527 asthma patients were initially enrolled in this study, of which 97 elderly patients and those with more severe cases of asthma were lost to follow-up. Thus, a total of 430 patients were valid for analysis using self-rate data. Nevertheless, occasional negative returns were obtained; almost all of the outcomes were rated as "No change", "Moderate effective", or "Very effective". In addition, 80% of the patients were satisfied with this treatment. Moreover, 391 (91.4% ) patients were somewhat improved after SAAT in 2009, and further improvement was observed in 2010. After SAAT, the average asthma-degree score decreased from 5.3 in 2008 to 4 in 2009 and, subsequently to 3.5 in 2010.

CONCLUSION

With pronounced patient satisfaction, SAAT can reduce the exacerbation severity and frequency, concomitant medications and asthma degree. Prolonging the treatment course might enhance the efficacy of SAAT.

OBJECTIVE

To evaluate the self-efficacy and satisfaction of asthma patients subjected to summer acupoint application treatment (SAAT).

METHODS

A two-year follow-up clinical study was conducted. Patients with asthma were treated by applying a herbal paste onto the Feishu (BL 13) and Fengmen (BL 12) acupoints on the three hottest days of summer, according to the traditional Chinese calendar, from 2008 to 2010. During a two-year follow-up, these patients were asked to

Updated prevalences of asthma, allergy, and airway symptoms, and a systematic review of trends over time for childhood asthma in Shanghai, China

BACKGROUND

The prevalence of asthma among Shanghai children has increased over time. This increase might be associated with changes in environmental exposures. Investigation of the time-trend of asthma and current prevalences is essential to understanding the causes.

OBJECTIVE

To estimate the current prevalences of asthma, allergies and other respiratory symptoms among Shanghai preschool children, and to investigate the time-trend of childhood asthma prevalence of from 1990 to 2011.

METHODS

From April 2011 to April 2012, the CCHH (China, Children, Homes, Health) cross-sectional study was conducted in Shanghai. Questionnaires were distributed to 17,898 parents or guardians of preschool children from 72 kindergartens in 5 districts. Previous similar studies were also summarized by a systematic literature review.

RESULTS

From a total of 14,884 questionnaires for 3-7 year old children, prevalences of the following diseases and symptoms were calculated: asthma 10.2%, wheeze (ever) 28.1%, pneumonia (ever) 33.5%, otitis media 11.0%, rhinitis (ever) 54.1%, hay fever 12.2%, eczema (ever) 22.7%, and food allergy 15.7%. Urban children had higher prevalences of most symptoms than suburban children. The prevalence of asthma has increased significantly, almost five-fold, from 2.1% in 1990 to 10.2% in the present study. The prevalence of asthma in boys was higher than in girls in the present study and in all reviewed studies.

CONCLUSIONS

Asthma, allergy and airway symptoms are common among preschool children in Shanghai. The prevalence of childhood asthma in Shanghai has increased rapidly from 1990 to 2011.

Allergic sensitization and the environment: latest update

The prevalence of asthma and other allergic diseases is still increasing both in developed and developing countries. Allergic sensitization against common inhalant allergens is common and, although not sufficient, a necessary step in the development of allergic diseases. Despite a small number of proteins from certain plants and animals being common allergens in humans, we still do not fully understand who will develop sensitization and to which allergens. Environmental exposure to these allergens is essential for the development of sensitization, but what has emerged clearly in the literature in the recent years is that the adjuvants to which an individual is exposed at the same time as the allergen are probably an equally important determinant of the immune response to the allergen. These adjuvants act on all steps in the development of sensitization from modifying epithelial barriers, to facilitating antigen presentation, to driving T-cell responses, to altering mast cell and basophil hyperreactivity. The adjuvants come from biogenic sources, including microbes and the plants and animals that produce the allergens, and from man-made sources (anthropogenic), including unintended by-products of combustion and chemicals now ubiquitous in modern life. As we better understand how individuals are exposed to these adjuvants and how the exposure influences the likelihood of an allergic response, we may be able to design individual and community-level interventions that will reverse the increase in allergic disease prevalence, but we are not there yet.

Integrated traditional Chinese medicine for childhood asthma in Taiwan: a Nationwide cohort study

Background

Traditional Chinese medicine (TCM) is the most commonly used alternative therapy in children with asthma, especially in the Chinese community. This study aimed to investigate the effects of the government-sponsored Outpatient’s Healthcare Quality Improvement (OHQI) project with integrated TCM treatment on childhood asthma.

Methods

This study used the Longitudinal Health Insurance Database 2000, which is a part of the Taiwan National Health Insurance Research Database (NHIRD). Children with diagnosed asthma and aged under 15 years from 2006–2010 were enrolled. They were collated into 3 groups: (1) subjects treated with non-TCM; (2) subjects treated with single TCM; and (3) subjects treated with integrative OHQI TCM. The medical visits and the cost of treatment paid by the Bureau of National Health Insurance (BNHI) to the outpatient, emergency room, and inpatient departments were evaluated for the study subjects within 1 year of the first asthma diagnosis during the study period.

Results

Fifteen multi-hospitals, including 7 medical centers, and 35 TCM physicians participated in OHQI during the study period. A total of 12850 children from the NHIRD database were enrolled in this study, and divided as follows: 12435 children in non-TCM group, 406 children in single TCM group, and 9 children in integrative OHQI TCM group. Although the total medical cost paid by the BNHI per patient in the integrative OHQI TCM group was greater than that in the non-OHQI groups, the patients in the integrative OHQI TCM group exhibited greater therapeutic effects, and did not require ER visits or hospitalization. In addition, ER visits and hospitalization among patients who received a combination of conventional therapy with integrated TCM were lower than those among patients who underwent conventional therapy alone or single TCM treatment.

Conclusions

Asthmatic children at partly controlled level under conventional therapy may benefit from adjuvant treatment with integrated TCM.

Home dampness, childhood asthma, hay fever, and airway symptoms in Shanghai, China: associations, dose-response relationships, and lifestyle's influences

Numerous studies of associations between dampness and respiratory diseases have been conducted, but their implications remain inconclusive. In this study of 13,335 parent-reported questionnaires (response rate: 85.3%), we analyzed associations between home dampness and asthma and related symptoms in 4- to 6-year-old children in a cross-sectional study of Shanghai. Indicators of home dampness were strongly and significantly associated with dry cough, wheeze, and rhinitis symptoms. In the current residence, children with visible mold spots (VMS) exposure had 32% higher risk of asthma (adjusted OR, 95% CI: 1.32, 1.07-1.64); damp clothing and/or bedding (frequently) was strongly associated with dry cough (1.78, 1.37-2.30); condensation on windows was strongly associated with hay fever (1.60, 1.27-2.01). In the early-life residence, VMS or damp stains (frequently) were strongly associated with dry cough (2.20, 1.55-3.11) and rhinitis ever (1.57, 1.11-2.21). Associations between dampness and diseases among children with or without family history of atopy were similar. The total number of dampness indicators had strong dose-response relationships with investigated health outcomes. Actions, including opening windows of the child's room at night and cleaning the child's room frequently, could potentially mitigate 25% of home VMS, thereby preventing more than 1.5% of attributable risk of the studied symptoms.

Association between β2-adrenoceptor gene polymorphisms and asthma risk: an updated meta-analysis

Background

Evidence is increasingly accumulated about multiple roles for the β2-adrenoceptor gene in asthma. The results were inconsistent partly due to small sample sizes. To assess the association between β2-adrenoceptor gene polymorphisms and asthma risk, a meta-analysis was performed.

Methods

We comprehensively searched the PubMed, EMBASE, BIOSIS Previews databases and extracted data from all eligible articles to estimate the association between β2-adrenoceptor gene polymorphisms and asthma risk. The pooled odds ratio (OR) with 95% confidence intervals (CIs) were calculated.

Results

Thirty-seven studies involving 6648 asthma patients and 15943 controls were included in the meta-analysis. Overall, significant associations were found in allelic genetic model (OR = 1.06, 95% CI = 1.01∼1.12), recessive genetic model (OR = 1.11, 95% CI = 1.02∼1.21) for Arg/Gly16. Stratified by ethnicity and age, significant associations were also found in Asian population in allelic genetic model, recessive genetic model and addictive model. For Gln/Glu27, no significant association was found when we combined all eligible studies. Age stratification showed significant associations in adults in allelic genetic model and recessive genetic model, but no significant association was found among Asians and Caucasians in ethnicity stratification.

Conclusions

This meta-analysis implied that the β2-adrenoceptor Arg/Gly16 polymorphism was likely to contribute to asthma risk in Asian population. Gln/Glu27 polymorphism might be a contributor to asthma susceptibility for adults.

The expression of a novel anti-inflammatory cytokine IL-35 and its possible significance in childhood asthma

Interleukin-35 (IL-35) is a novel anti-inflammatory cytokine and has been shown to play an important role in maintaining immune homeostasis. However, the effect of IL-35 on human asthma remains unclear. The present study is to investigate the expression and significance of IL-35 in childhood asthma. Forty-one asthmatic children and forty-two healthy controls were recruited in Qilu Children's Hospital of Shandong University. Serum total immunoglobulin E level was measured by radioimmunosorbent test. Peripheral blood eosinophils were counted using BC-5800 Automatic Blood Cell Analyzer. IL-35 mRNA in peripheral blood mononuclear cells was detected by quantitative real-time polymerase chain reaction. Serum IL-35, IL-4 and interferon-γ levels were measured using enzyme-linked immunosorbent assay. The correlations among the above indexes were also analyzed using Pearson's method. Our results showed that serum total IgE, eosinophil count and serum IL-4 were significantly increased in asthmatic children compared with control children, and serum IFN-γ level in asthmatic patients was obviously lower than that in healthy controls. We also found that there was an obviously positive correlation between serum IgE and IL-4 levels in asthmatic patients. In addition, significantly negative correlation was found between serum total IgE and IFN-γ levels. More importantly, we found that the expression of IL-35 mRNA and protein was both down-regulated in asthmatic children, and serum IL-35 level was inversely related to serum IL-4 level. Moreover, significantly positive correlation was also found between serum IL-35 and IFN-γ levels. The results suggest that the decreased expression of IL-35 could be involved in the pathogenesis of childhood asthma.

Epidemiology of bronchial asthma and asthma control assessment in Henan Province, China

BACKGROUND

Prevalence of bronchial asthma, asthma treatment assessment, and estimation of the control level among asthma patients in Henan Province, China are reported in this paper.

METHODS

We selected 10 among the 109 cities and districts in Henan province using a multistage stratified cluster random sampling method. A total of 500 households from each city and district were chosen. Approximately 20,000 residents from a total of 5,000 households were randomly selected to answer a questionnaire recommended by the China Asthma Alliance. Asthma patients were asked to answer a detailed questionnaire using the symptom-based guidelines to assess the levels of disease control.

RESULTS

The overall prevalence of asthma was 0.73% ± 0.12%. Urban and rural residents had asthma prevalence rates of 1.1% ± 0.23% (88/7,924) and 0.48% ± 0.12% (57/11,792), respectively. Among the asthma patients, only 33.8% (52) received regular medication, 25% (13) used oral glucocorticoids, and 71.1% (37) used oral theophylline. The classified control levels of patients were as follows: 33.1% controlled, 49.7% partially controlled, and 17.2% uncontrolled. A total of 38.5% and 27.5% of regularly and irregularly treated asthma patients reached controlled level, respectively. The two groups significantly differed in asthma control level.

CONCLUSION

Asthma prevalence is low in Henan Province, China. Urban residents have higher prevalence of asthma than rural residents do. Patients with asthma receive insufficient medication, resulting in suboptimal asthma control. Improvement in diagnosis and treatment of asthma patients is urgently needed.

Gender-specific differences in associations of overweight and obesity with asthma and asthma-related symptoms in 30 056 children: result from 25 districts of Northeastern China

OBJECTIVE

The relationship between obesity and allergic respiratory diseases in childhood is still controversial. Furthermore, significant debate on the issue of whether or not gender modifies this association also exists due to inconsistent findings. The objective of this study is to evaluate the association between obesity and respiratory health in children, and to investigate the modifications of gender on this association.

METHODS

30 056 children (aged 2-14 years) were randomly selected from 25 districts within 7 cities in Northeastern China in 2009. A standard questionnaire from the American Thoracic Society was used to characterize the children's histories of respiratory symptoms and illnesses. Child weight and height were measured, and obesity was calculated with an age and sex-specific body mass index.

RESULTS

The overall prevalence rates of obesity and overweightness were 14.08% and 12.32%, respectively. Compared to the children with normal body weights, asthma and asthma-related symptoms were more prevalent in overweight and obese children. Analysis stratified by gender showed that obesity was associated with more respiratory symptoms and diseases in females than in males. A significant association between obesity and diagnosed asthma [adjusted odds ratio (aOR) = 1.28; 95% confidence interval (CI): 1.02-1.60], as well as current wheezing (aOR = 1.46; 95%CI: 1.20-1.79) was found in females but not in males.

CONCLUSIONS

There is an association between asthma symptoms and obesity in these Chinese children, and obesity had a significantly larger effect on females than males.

Monosodium glutamate intake, dietary patterns and asthma in Chinese adults

Objectives

Emerging evidence shows that diet is related to asthma. The aim of this analysis was to investigate the association between monosodium glutamate (MSG) intake, overall dietary patterns and asthma.

Methods

Data from 1486 Chinese men and women who participated in the Jiangsu Nutrition Study (JIN) were analyzed. In this study, MSG intake and dietary patterns were quantitatively assessed in 2002. Information on asthma history was collected during followed-up in 2007.

Results

Of the sample, 1.4% reported ever having asthma. MSG intake was not positively associated with asthma. There was a significant positive association between ‘traditional’ (high loadings on rice, wheat flour, and vegetable) food pattern and asthma. No association between ’macho’ (rich in meat and alcohol), ‘sweet tooth’ (high loadings on cake, milk, and yoghurt) ‘vegetable rich’ (high loadings on whole grain, fruit, and vegetable) food patterns and asthma was found. Smoking and overweight were not associated with asthma in the sample.

Conclusion

While a ‘Traditional’ food pattern was positively associated with asthma among Chinese adults, there was no significant association between MSG intake and asthma.