Gut microbiota and risk of polycystic ovary syndrome: Insights from Mendelian randomization.

Background: Polycystic ovary syndrome (PCOS) is a multifaceted endocrine and metabolic syndrome with complex origins and pathogenesis that has not yet been fully elucidated. Recently, the interconnection between gut microbiota and metabolic diseases has gained prominence in research, generating new insights into the correlation between PCOS and gut microbiota composition. However, the causal link between PCOS and gut microbiota remains relatively unexplored, indicating a crucial gap in current research. Methods: We conducted a two-sample Mendelian randomization analysis using summary statistics obtained from the MiBioGen Consortium's extensive genome-wide association studies (GWAS) meta-analysis, focusing on the gut microbiota. Summary statistics for PCOS were acquired from the FinnGen Consortium R7 release data. Various statistical approaches, including inverse variance weighted, MR-Egger, maximum likelihood, weighted model, and weighted median, have been employed to investigate the causal association between the gut microbiota and PCOS. Additionally, we performed a reverse causal analysis. Cochran's Q statistic was used to assess the heterogeneity of the instrumental variables. Regarding the relationships between PCOS and specific genera within the gut microbiota, a significance level of P < 0.05 was observed, but only when q ≥ 0.1. Results: Our analysis revealed that specific microbial genera, namely Bilophila (P = 4.62 × 10-3), Blautia (P = 0.02), and Holdemania (P = 0.04), displayed a protective effect against PCOS. Conversely, the presence of the Lachnospiraceae family of bacteria was associated with a detrimental effect on PCOS (P = 0.04). Furthermore, reverse Mendelian randomization analysis confirmed the significant influence of Lachnospiraceae on PCOS. No significant variations in instrumental variables or evidence of horizontal pleiotropy were observed. Conclusions: The results revealed a definitive causal link between PCOS and the presence of Bilophila, Blautia, Holdemania, and Lachnospiraceae in the gut microbiota. This discovery could provide pivotal insights, leading to novel preventive and therapeutic approaches for PCOS.

Family-centered care management strategies for term and near-term neonates with brief hospitalization in a level III NICU in Shenzhen, China during the time of COVID-19 pandemic.

BACKGROUND: Adopting the family-centered care (FCC) approach in the neonatal care has been shown to improve breastfeeding rate and parental satisfaction. To minimize the transmission of COVID-19, family visit in neonatal intensive care unit (NICU) was suspended in China. In order to maintain the benefits of FCC, the Hong Kong University-Shenzhen Hospital NICU modified FCC strategies. We evaluated the effects of new strategies and aimed to share our results and experience with other NICUs during the COVID-19 pandemic. METHODS: Using prospectively collected hospital databases, we retrospectively compared the demographic and clinical data of neonates, rates of breastfeeding at discharge, nosocomial infection and parental satisfaction one month before (open group) and after (closed group) the implementation of alternative FCC management strategies when family visit was suspended during COVID-19 pandemic. RESULTS: During the COVID-19 pandemic, we organized a multidisciplinary task force and adopted strategies of triage and screening, management of suspected infants, and breastfeeding promotion with effective communication. The nosocomial infection rate and parental satisfaction for open and closed groups (144 and 108 term and near-term neonates with brief hospitalization, respectively) were not different (1% vs. 0%, p = 1.00; 98.6 vs. 98.8, p = .80; respectively). Breastfeeding rate at discharge decreased but the difference was not significant (74% vs. 80%, p = .29). CONCLUSIONS: In our experience, in term and near-term neonates with brief hospitalization, the alternative FCC strategies maintained high parental satisfaction without increased nosocomial infection rate, but strong support for breastfeeding was needed. Through multidisciplinary collaboration, the continuation of "modified" FCC in a level III NICU is feasible in the context of COVID-19 pandemic with reduced family visitation and participation in the care.

Efficacy of Huaiqihuang granules as adjuvant therapy for bronchial asthma in children: a real-world study. / æ§æžé»„é¢—ç²’è¾ åŠ©æ²»ç–—å„¿ç«¥æ”¯æ°”ç®¡å“®å–˜ç–—æ•ˆçš„çœŸå®žä¸–ç•Œç ”ç©¶.

OBJECTIVES: To study the efficacy of Huaiqihuang granules as adjuvant therapy for bronchial asthma in children. METHODS: A multicenter, prospective, and registered real-world study was performed for the children, aged 2-5 years, who had a confirmed diagnosis of bronchial asthma in the outpatient service of 21 hospitals in China. Among these children, the children treated with medications for long-term asthma control (inhaled corticosteroid and/or leukotriene receptor antagonist) without Huaiqihuang granules were enrolled as the control treatment group, and those treated with medications for long-term asthma control combined with Huaiqihuang granules were enrolled as the combined treatment group. The medical data of all children were collected. Outpatient or telephone follow-up was performed at weeks 4, 8, 12, 20, 28, and 36 after treatment, including asthma attacks and rhinitis symptoms. A statistical analysis was performed for the changes in these indices. RESULTS: There was no significant difference in the frequency of asthma attacks or rhinitis attacks between the two groups before treatment (P>0.05). After treatment, the combined treatment group had significantly lower frequencies of asthma attacks, severe asthma attacks, and rhinitis attacks compared with the control treatment group (P<0.05). There was no signification difference in the incidence rate of adverse reactions between the two groups (P=0.667). CONCLUSIONS: Huaiqihuang granules in addition to medications for long-term asthma control can alleviate the symptoms of bronchial asthma and rhinitis and improve the level of asthma control in children with bronchial asthma, with good safety and little adverse effect. Citation.

Pediatric allergy and immunology in China.

Over the past 30 years, China has enjoyed rapid economic development along with urbanization at a massive scale that the world has not experienced before. Such development has also been associated with a rapid rise in the prevalence of allergic disorders. Because of the large childhood population in the country, the burden of childhood allergic disorders has become one of the major challenges in the healthcare system. Among the Chinese centers participating in the International Study of Asthma and Allergies in Childhood, the data clearly showed a continuing rise in the prevalence of asthma, allergic rhinitis, and atopic eczema. However, the discipline of pediatric allergy in mainland China is still in its infancy due to the lack of formal training program and subspecialty certification. Clinicians and researchers are increasingly interested in providing better care for patients with allergies by establishing pediatric allergy centers in different regions of the country. Many of them have also participated in national or international collaborative projects hoping to answer the various research questions related to the discipline of pediatric allergy and immunology. It is our hope that the research findings from China will not only improve the quality of care of affected children within this country but also the millions of patients with allergies worldwide.

Should recommendations about starting inhaled corticosteroid treatment for mild asthma be based on symptom frequency: a post-hoc efficacy analysis of the START study.

BACKGROUND: Low-dose inhaled corticosteroids (ICS) are highly effective for reducing asthma exacerbations and mortality. Conventionally, ICS treatment is recommended for patients with symptoms on more than 2 days per week, but this criterion has scant evidence. We aimed to assess the validity of the previous symptom-based cutoff for starting ICS by establishing whether there was a differential response to budesonide versus placebo for severe asthma exacerbations, lung function, and asthma symptom control across subgroups identified by baseline asthma symptom frequency. METHODS: We did a post-hoc analysis of the 3 year inhaled Steroid Treatment As Regular Therapy (START) study, done in 32 countries, with clinic visits every 3 months. Patients (aged 4-66 years) with mild asthma diagnosed within the previous 2 years and no previous regular corticosteroids were randomised to receive once daily, inhaled budesonide 400 µg (those aged <11 years 200 µg) or placebo. Coprimary outcomes for this analysis were time to first severe asthma-related event (SARE; hospital admission, emergency treatment, or death) and change from baseline in lung function after bronchodilator. Interaction with baseline symptom frequency was investigated, with patients grouped by more than two symptom days per week and two or fewer symptom days per week (divided into no days to 1 day, and more than 1 day to 2 days). Analysis was done by intention to treat. FINDINGS: Of 7138 patients (n=3577 budesonide; n=3561 placebo), baseline symptom frequency was 0-1 days per week for 2184 (31%) participants, more than 1 and less than or equal to 2 symptom days per week for 1914 (27%) participants, and more than 2 symptom days per week for 3040 (43%) participants. For budesonide versus placebo, time to first SARE was longer across symptom frequency subgroups (hazard ratios 0·54 [95% CI 0·34-0·86] for 0-1 symptom days per week, 0·60 [0·39-0·93] for >1 to ≤2 symptom days per week, 0·57 [0·41-0·79] >2 symptom days per week, pinteraction=0·94), and the decline in postbronchodilator lung function was less at 3 years' follow-up (pinteraction=0·32). For budesonide versus placebo, severe exacerbations requiring oral or systemic corticosteroids were reduced (rate ratio 0·48 [0·38-0·61] 0-1 symptom days per week, 0·56 [0·44-0·71] >1 to ≤2 symptom days per week, and 0·66 [0·55-0·80] >2 symptom days per week, pinteraction=0·11), prebronchodilator lung function was higher, and symptom-free days were more frequent (p<0·0001 for all three subgroups), with no interaction by symptom frequency (prebronchodilator pinteraction=0·43; symptom-free days pinteraction=0·53). Similar results were noted when participants were classified by any guidelines criterion as so-called persistent versus so-called intermittent asthma. INTERPRETATION: In mild recent-onset asthma, once daily, low-dose budesonide decreases SARE risk, reduces lung function decline, and improves symptom control similarly across all symptom subgroups. The results do not support restriction of inhaled corticosteroids to patients with symptoms on more than 2 days per week and suggest that treatment recommendations for mild asthma should consider both risk reduction and symptoms. FUNDING: AstraZeneca.

Formoterol as reliever medication in asthma: a post-hoc analysis of the subgroup of the RELIEF study in East Asia.

BACKGROUND: As-needed formoterol can effectively relieve asthma symptoms. Since budesonide/formoterol is available as maintenance and reliever therapy in Asia, formoterol is now being used as-needed, but always with concomitant inhaled corticosteroids. The objective of this analysis was to assess the safety and efficacy of formoterol therapy in patients in East Asia (China, Indonesia, Korea, the Philippines and Singapore) with asthma. METHODS: Post-hoc analyses of data from the East Asian population of the RELIEF (REal LIfe EFfectiveness of Oxis® Turbuhaler® as-needed in asthmatic patients; study identification code: SD-037-0699) study were performed. RESULTS: This sub-group comprised 2834 randomised patients (formoterol n = 1418; salbutamol n = 1416) with mean age 35 years; 50.7% were male. 2678 patients completed the study. There was no significant difference in the total number of adverse events (AEs) reported in the formoterol and salbutamol groups (21.3% vs 20.9% of patients; p = 0.813), nor in the total number of serious AEs and/or discontinuations due to AEs (4.6% vs 5.5%, respectively; p = 0.323). Compared with salbutamol, formoterol was associated with a significantly longer time to first exacerbation (hazard ratio 0.86; p = 0.023) and a 14% reduction in the risk of any exacerbation (p < 0.05). Relative to salbutamol, mean adjusted reliever medication use throughout the study was significantly lower in the formoterol group (p = 0.017) and the risk of increased asthma medication use was 20% lower with formoterol (p = 0.005). CONCLUSIONS: Among patients with asthma in East Asia, as-needed formoterol and salbutamol had similar safety profiles but, compared with salbutamol, formoterol reduced the risk of exacerbations, increased the time to first exacerbation and reduced the need for reliever medication.

Prevalence and Treatment of Children's Asthma in Rural Areas Compared with Urban Areas in Beijing.

BACKGROUND: The prevalence of childhood asthma has been increasing in China. This study aimed to compare the prevalence, diagnosis, and treatment of asthmatic children from urban and rural areas in Beijing, China. METHODS: Schools, communities, and kindergartens were randomly selected by cluster random sampling from urban and rural areas in Beijing. Parents were surveyed by the same screening questionnaires. On-the-spot inquiries, physical examinations, medical records, and previous test results were used to diagnose asthmatic children. Information on previous diagnoses, treatments, and control of symptoms was obtained. RESULTS: From 7209 children in rural areas and 13,513 children in urban areas who completed screening questionnaires, 587 children were diagnosed as asthma. The prevalence of asthma in rural areas was lower than in urban areas (1.25% vs. 3.68%, χ2 = 100.80, P < 0.001). The diagnosis of asthma in rural areas was lower than in urban areas (48.9% vs. 73.9%, χ2 = 34.6, P < 0.001). Compared with urban asthmatic children (56.5%), only 35.6% of rural asthmatic children received inhaled corticosteroids (P < 0.05). The use of bronchodilators was also lower in rural areas than in urban areas (56.5% vs. 66.4%, χ2 = 14.2, P < 0.01). CONCLUSION: The prevalence of asthma in children was lower in rural areas compared with children in the urban area of Beijing. A considerable number of children were not diagnosed and inadequately treated in rural areas.

[Epidemiological survey of children asthma prevalence in Beijing urban area].

OBJECTIVE: To explore the prevalence, diagnosis and management of childhood asthma in Beijing urban area. METHODS: Multi-stage, stratified and random cluster sampling was used to recruit children born during November 1, 1995 to October 31, 2010 from Beijing or other provinces but residing in Beijing for over half a year. The same screening questionnaires for the third national epidemiological survey of children's asthma were distributed to parents of children at schools, kindergartens and communities during October 2010 to March 2011. Asthmatic children were picked among the screening-positive children based on on-the-spot inquiries, physical examinations, medical records and supporting test results. Further survey of asthmatics was carried out to investigate the diagnosis and treatment status of childhood asthma and other associated allergic diseases. All data required double entry by Epi-Info 3.5.3 software and were processed by SPSS 19.0. RESULTS: Among a total of 14 085 questionnaires, 13 513 were completed with a response rate of 95.94%. And 497 (3.68%) children were diagnosed with typical (n = 451, 3.34%) and cough variant (n = 46, 0.34%) asthma. Among them, 40.64% (202/497) were newly diagnosed and 59.36% (295/497) had been previously diagnosed with asthma. The prevalence of asthma was higher in boys than in girls (4.80% (345/1790) vs 2.40% (152/6323), χ(2) = 54.446, P < 0.01). The asthma prevalence of preschoolers (3 - < 7 years old) was the highest (5.05% (180/3563)). In the past two years, the symptoms of 69.42% (345/497) children persisted and the current two-year prevalence of asthma was 2.55% (345/13513). Among the 295 children with previous asthma, only 46.44% (137/295) received inhaled corticosteroids according to the Global Initiative for Asthma (GINA) and 82.37% (243/295) of them used antibiotics. CONCLUSIONS: The prevalence of asthma is 3.68% in children under 14 years old in Beijing urban area and it varies in children with different genders and ages. A considerable number of children are not diagnosed or treated properly. And the management of asthma requires further improvement.

[Exhaled nitric oxide levels in school children of Beijing].

OBJECTIVE: To learn the normal values of exhaled nitric oxide (eNO) in children. METHOD: School children in Beijing from 11 to 18 years of age were included in the study. All the students were assigned into two groups: normal group and abnormal group (with allergic disease) according to the International Study of Asthma and Allergy in Childhood questionnaires. eNO, peak expiratory flow rate and sensitization were measured. RESULT: Totally 395 students were screened out as normal subject (male: 177, female: 218). The eNO level was not significantly different between genders (P > 0.05), but was associated positively with age in both male and female group (P = 0.008 and P = 0.05 respectively) and associated with height in male students (P = 0.02). The geometric mean value of eNO was 11.22 ppb (parts per billion, ppb = 10(9)) in children aged from 11 to 14 years and 14.13 ppb in children aged from 14 to 18 years, with 95% confidence interval 4.17 - 30.20, 5.50 - 36.31 ppb. The eNO level was significantly increased in children who "ever had asthma or wheezing" (n = 68), and children who "ever had rhinitis" (n = 96) compared with normal subjects (P = 0.001 and P = 0.008). The geometric mean value of eNO was 16.98 ppb in children with positive skin prick test and was significantly increased as compared with children with negative skin prick test with eNO level at 11.75 ppb (P = 0.001). CONCLUSION: eNO level varied between 10.72 ppb and 13.80 ppb in normal children 11 - 18 years of age, and was positively associated with age and height, but not with gender. eNO level increased significantly in children with wheezing and atopy.

Prevalence of asthma among Chinese adolescents living in Canada and in China.

BACKGROUND: Studies of the prevalence of asthma among migrating populations may help in identifying environmental risk factors. METHODS: We analyzed data from Vancouver, Canada, and from Guangzhou, Beijing and Hong Kong, China, collected during phase 3 of the International Study of Asthma and Allergies in Childhood. We subdivided the Vancouver adolescents according to whether they were Chinese immigrants to Canada, Canadian-born Chinese or Canadian-born non-Chinese. We compared the prevalence of asthma and wheezing among Chinese adolescents born in Canada, Chinese adolescents who had immigrated to Canada and Chinese adolescents living in China. RESULTS: Of 7794 Chinese adolescents who met the inclusion criteria, 3058 were from Guangzhou, 2824 were from Beijing, and 1912 were from Hong Kong. Of 2235 adolescents in Vancouver, Canada, 475 were Chinese immigrants, 617 were Canadian-born Chinese, and 1143 were Canadian-born non-Chinese. The prevalence of current wheezing among boys ranged from 5.9% in Guangzhou to 11.2% in Canadian-born Chinese adolescents. For girls, the range was 4.3% in Guangzhou to 9.8% in Canadian-born Chinese adolescents. The prevalence of ever having had asthma ranged from 6.6% to 16.6% for boys and from 2.9% to 15.0% for girls. Prevalence gradients persisted after adjustment for other environmental variables (odds ratios for ever having had asthma among Canadian-born Chinese compared with native Chinese in Guangzhou: 2.72 [95% confidence interval 1.75-4.23] for boys and 5.50 [95% confidence interval 3.21-9.44] for girls; p < 0.001 for both). Among Chinese adolescents living in Vancouver, the prevalence of ever wheezing increased with duration of residence, from 14.5% among those living in Canada for less than 7 years to 20.9% among those living their entire life in Canada. The same pattern was observed for the prevalence of ever having had asthma, from 7.7% to 15.9%. INTERPRETATION: Asthma symptoms in Chinese adolescents were lowest among residents of mainland China, were greater for those in Hong Kong and those who had immigrated to Canada, and were highest among those born in Canada. These findings suggest that environmental factors and duration of exposure influence asthma prevalence.

The Inhaled Steroid Treatment As Regular Therapy in Early Asthma (START) study 5-year follow-up: effectiveness of early intervention with budesonide in mild persistent asthma.

BACKGROUND: The Inhaled Steroid Treatment as Regular Therapy in Early Asthma (START) study enrolled 7241 patients aged 5 to 66 years with recent-onset, mild persistent asthma to assess early intervention with the inhaled corticosteroid budesonide on long-term asthma control. OBJECTIVE: The open-label phase of the START study was included to determine the effect on lung function and asthma control of adding budesonide to the reference group patients who had not initially received inhaled corticosteroids. METHODS: Patients were randomized to double-blind treatment with budesonide, 200 mug (those aged < 11 years) or 400 mug once daily, or placebo plus the usual asthma therapy for 3 years, after which all patients received 2 years of open-label treatment with budesonide once daily. RESULTS: During the full 5-year study period, postbronchodilator FEV(1) percent predicted decreased, irrespective of randomized treatment during the double-blind phase, by an average of 2.22% (SE, 0.15%). However, patients with inhaled budesonide in the double-blind phase had a significantly lower risk (odds ratio, 0.61; P < .001) of a severe asthma-related event during the full 5-year study period than those in the reference group. Moreover, patients in the reference group used more additional asthma medications during both the open-label and double-blind phases. CONCLUSIONS: In mild persistent asthma early intervention with inhaled budesonide was associated with improved asthma control and less additional asthma medication use.

[Effects of 2-n-nonyl-1,3-dioxolane as an enhanceron transdermal absorption of Salvia miltiorrhiza gel].

OBJECTIVE: To choose the most suitable concentration of 2-n-nonyl-1,3-dioxolane as a penetration enhancer in tanshinone gel preparation. METHOD: In vitro, transdermal absorption was studied using improved Frans equipment and rats skin. Tanshinone II A was tested by HPLC. RESULT: The 4.0% concentration of 2-n-nonyl-1,3-dioxolane enhanced the transdermal absorption significantly in the preparation. CONCLUSION: 2-n-nonyl-1,3-dioxolane was a new effective permeaton enhancer.

Effectiveness of early budesonide intervention in Caucasian versus Asian patients with asthma: 3-year results of the START study.

OBJECTIVE AND BACKGROUND: Few studies have assessed the effectiveness of inhaled corticosteroid therapy exclusively in Asian patients with asthma. The present analysis compared the efficacy of early intervention with inhaled budesonide in Caucasian and Asian patients over the first 3 years of the inhaled Steroid Treatment As Regular Therapy in early asthma study. METHODS: Patients aged 5-66 years with mild persistent asthma of

Effects of early intervention with inhaled budesonide on lung function in newly diagnosed asthma.

STUDY OBJECTIVES: Asthmatic patients lose lung function faster than normal subjects. The effectiveness of early intervention with inhaled corticosteroids on this decline in lung function is not established in recent-onset disease. DESIGN: The Inhaled Steroid Treatment as Regular Therapy in Early Asthma study was a randomized, double-blind study in 7,165 patients (5 to 66 years old), with persistent asthma for < 2 years to determine whether early intervention with low-dose inhaled budesonide prevents severe asthma-related events and the decline in lung function. Patients received budesonide (200 mug qd for children < 11 years old and 400 mug qd for others) or placebo for 3 years in addition to usual asthma medications. RESULTS: Treatment with budesonide significantly improved prebronchodilator and postbronchodilator FEV(1) percentage of predicted and reduced the mean declines from baseline for postbronchodilator FEV(1) at 1 year and 3 years: - 0.62% and - 1.79% for budesonide and - 2.11% and - 2.68% for placebo, respectively (p < 0.001). The decline was more marked for male patients, active smokers, and patients > 18 years old, and the smallest treatment effects were in adolescents. CONCLUSIONS: Long-term, once-daily treatment with low-dose budesonide improved both prebronchodilator and postbronchodilator FEV(1) in patients with recent-onset, persistent asthma, and reduced the loss of lung function over time.

Early intervention of recent onset mild persistent asthma in children aged under 11 yrs: the Steroid Treatment As Regular Therapy in early asthma (START) trial.

Inhaled corticosteroids are known to be effective in persistent asthma, but their long-term effect in mild persistent disease of recent onset, which is particularly relevant in children, requires clarification. The objective of this study was to determine the long-term efficacy of regular inhaled low-dose budesonide in children aged <11 yrs with mild persistent asthma with onset within 2 yrs of enrollment. Children aged 5-10 yrs formed part of the population of the inhaled Steroid Treatment As Regular Therapy in early asthma (START) study, and they were randomized in a double-blind manner to treatment with once daily budesonide 200 microg or placebo via Turbuhaler in addition to usual clinical care and other asthma medication. The double-blind treatment phase continued for 3 yrs. Of the 1974 children, 1000 in the budesonide group and 974 in the placebo group, were analyzed for efficacy. Addition of once-daily budesonide to usual care was associated with a significant increase in the time to first severe asthma-related event (SARE) and significantly reduced risk of SARE over 3 yrs. The hazard ratio relative to usual care (placebo) was 0.60 (95% confidence interval: 0.40-0.90; p = 0.012), with a relative risk reduction of 40%. Children receiving budesonide also needed significantly less intervention with other inhaled corticosteroids (12.3% vs. 22.5% over 3 yrs; p < 0.01), with trends towards decreased usage of oral/systemic corticosteroids and inhaled short-acting beta2-agonists. Budesonide treatment also had a significant beneficial effect on lung function relative to placebo. In conclusion, early intervention adding once-daily budesonide to usual care in children with mild, persistent asthma of recent onset reduces the long-term risk and frequency of SAREs and improves lung function compared with usual care alone.

[Disparity of asthma prevalence in Chinese schoolchildren is due to differences in lifestyle factors].

OBJECTIVE: To investigate the environmental lifestyle risk factors which may explain the disparity of asthma prevalence in the Chinese population. METHODS: In a cross-sectional study, 10 902 schoolchildren were recruited from Hong Kong (n = 3110), Beijing (n = 4277), and Guangzhou (n = 3565) using the ISAAC Phase II protocol. The average age of the children among three cities was 10.1-10.4 years and 50%-53% were male. Each subject was given an ISAAC Phase II questionnaire to be completed by the parents or guardians. Random subgroups of at least 1000 children from each city, added up to 3479 children underwent skin-prick testing. The sensitivity to eight common aeroallergens was assessed. Logistic regression analysis was used to determine the environmental and lifestyle risk factors for asthma and atopy. RESULTS: The prevalence of wheezing in the past 12 months (Hong Kong, 5.8%; Beijing, 3.8%; Guangzhou, 3.4%) was significantly higher in schoolchildren from Hong Kong than that from the Mainland of China (OR 1.64, 95% CI 1.35-1.99). Multivariate logistic regression analyses revealed that the use of gas cooking (OR 2.08, 95% CI 1.32-3.26), foam pillow (OR 1.94, 95% CI 1.19-3.16), and house dampness (OR 1.84, 95% CI 1.25-2.71) were significant risk factors for "current wheezing". The use of cotton quilt (OR 0.70, 95% CI 0.56-0.87), breast-feeding (OR 0.79, 95% CI 0.66-0.96), and attendance of daycare (OR 0.73, 95% CI 0.59-0.88) were protective factors against "current wheezing". When a summary measure of these variables was introduced into a regression model, the Mainland residency was no longer associated with "current asthma" or "current wheezing" suggesting that either these factors or other unmeasured factors associated with above factors are responsible for the lower prevalence of asthma in the Mainland of China. CONCLUSION: Several environmental and lifestyle factors represented characteristic of life in Mainland of China, including breast feeding, attendance of daycare, use of cotton quilt, use of pillow other than foam pillow, use of cooking fuel other than gas, and the absence of damp spots on the walls or ceiling, were the significant risk factors contributed to the disparity of asthma prevalence in children from Hong Kong and the Mainland of China.

[Determination of positive bronchodilating response using impulse oscillation system in children].

OBJECTIVE: Impulse oscillation system (IOS) as an approach to lung function determination is suitable for children, especially for preschool children in that it only requires the individual to be examined to breathing stably with tidal volume. However, until now there have been no uniformly agreed criteria for positive bronchial reversibility test in clinical practice. A screening method was applied to seek for answer when this question in the hope of providing objective evidence for clinical diagnosis of respiratory diseases, esp. asthma. METHODS: One hundred and fifty-six children patients during asthma attack were recruited randomly for this study from January to December, 2004. These patients included 103 boys and 53 girls aged from 5 to 18 years with mean age of 8.84 +/- 2.58 years, who visited the doctors in the Clinical and Educational Centre for Asthma, Capital Institute of Pediatrics and were diagnosed as asthma. Maximal expiratory flow volume and IOS lung function were determined followed by bronchodilator reversibility test in all patients. The sensitivity and specificity of IOS parameters, total respiratory impedance (Zrs), respiratory resistance at 5 Hz (R5) and reactance at 5 Hz (X5) for diagnosing asthma at different improvement levels after inhalation of bronchodilator were calculated respectively using forced expiratory volume in first second (FEV(1)) and maximal mid-expiratory flow (MMEF) as gold standard. And the regression equation between parameters of lung function which were determined with the two different methods was analyzed. RESULTS: After inhalation of bronchodilator, the lung function of the children was improved significantly (P < 0.01), with the FEV(1), MMEF increase and Zrs, R5, and X5 decrease. There were significantly positive correlations (P < 0.01) between the improvement rate of parameters of lung functions determined with the two methods, and the highest correlation coefficients existed between X5 and FEV(1) and MMEF (respectively 0.676, 0.571), correlation coefficients between X5 and Zrs ranked second (0.519 and 0.505, respectively). When an increase of FEV(1) equal to or greater than 15%, or increase of MMEF equal to or greater than 30% was used as reference for positive bronchial reversibility, the sensitivity and specificity were relatively high for considering positive bronchial reversibility test with at least 20% decrease of Zrs, R5, and 30% decrease of X5 with IOS lung function. The sensitivity and specificity of Zrs, R5 and X5 calculated from FEV(1) were 0.62, 0.51; 0.49, 0.54; 0.70, and 0.54, respectively. The sensitivity and specificity of Zrs, R5 and X5 calculated from MMEF were 0.63, 0.54; 0.53, 0.60; 0.60, and 0.58, respectively. The regression equation showed that the decrease of Zrs, R5 and X5 corresponding to 15% increase of FEV(1) and 30% increase of MMEF were 21.7%, 21.3%; 19.9%, 19.5%; 30.1%, and 29.6%, respectively. CONCLUSION: When lung function is determined with IOS in children, only when decrease of Zrs and R5 is equal to or more than 20% and decrease of X5 is 30% or more after inhalation of bronchodilator, can the bronchial reversibility test be considered as positive.