Interaction effects of breastfeeding and passive smoking on asthma and asthma related symptoms among children / 中华预防医学杂志

<p><b>OBJECTIVE</b>To evaluate the interaction effects of breastfeeding and passive smoking on asthma and asthma related symptoms among children.</p><p><b>METHODS</b>Using a cluster random sampling method, 2 elementary schools and 1 kindergarten were randomly selected from 7 cities of Liaoning province. The resulting 25 elementary schools and 50 kindergartens were included, and 31 049 children from the selected schools living up to 2 years were recruited in this survey. The information about the children's type of feeding up, living environment, passive smoking exposure, respiratory diseases and symptoms were collected. The interaction effects of breastfeeding and passive smoking on asthma and asthma related symptoms (persistent cough,persistent phlegm, current wheeze and allergic rhinitis) were evaluated with Glimmix procedure.</p><p><b>RESULTS</b>There were 31 049 children involved in this investigation. The age was (8.32 ± 2.75) years old. There were 23 987 (77.26%) children with breastfeeding and 11 820 (38.07%) children with passive smoking. The prevalence of asthma and allergic rhinitis were 6.22%(1491/23 987), 4.67%(1120/23 987) in children with breastfeeding, and were 7.70%(544/7062), 5.48%(387/7062) in children without breastfeeding,compared to the children without breastfeeding, the children with breastfeeding had lower risk of asthma(OR = 0.79, 95%CI:0.72-0.88) and allergic rhinitis(OR = 0.85, 95%CI:0.75-0.95); The prevalence of current wheeze was 7.89%(929/11 770) in children with father smoking, and was 5.37%(1036/19 279) in children without father smoking, compared to the children without father smoking, the children with father smoking increased the risk of current wheeze(OR = 1.51, 95%CI:1.38-1.65). The prevalence of persistent cough was 18.96%(51/269) in children with mother smoking, and was 9.51%(2926/30 780) in children without mother smoking,compared to the children without mother smoking, the children with mother smoking increased the risk of persistent cough(OR = 2.23, 95%CI:1.64-3.03). The prevalence of persistent phlegm was 5.69%(871/5316) in children with anyone smoking, and was 3.50%(550/15 733) in children without anyone smoking, compared to the children without anyone smoking, the children with anyone smoking increased the risk of persistent phlegm(OR = 1.67, 95%CI:1.49-1.86).Glimmix procedure analysis showed there was a significant interaction effects between breastfeeding and passive smoking. The estimated OR for father smoking among breastfeeding children were consistently lower than those among non-breastfeeding children for asthma. The estimated OR for mother smoking among breastfeeding children were consistently lower than those among non-breastfeeding children for allergic rhinitis. The estimated OR for anyone smoking among breastfeeding children were consistently lower than those among non-breastfeeding children for asthma and allergic rhinitis(all P values < 0.05).</p><p><b>CONCLUSION</b>Breastfeeding decreases the detrimental effects of passive smoking on asthma and asthma related symptoms in children.</p>

Interactive effects of environmental tobacco smoke and pets ownership on respiratory diseases and symptoms in children / 中华儿科杂志

<p><b>OBJECTIVE</b>Over the past few decades, secondhand smoke exposure among children become more serious and with China's implementation of the national policy of family planning and the family structure change, domestic pet has gradually become popular. This survey aimed to investigate the interactive effects of pet ownership and environmental tobacco smoke (ETS) on children's respiratory diseases and symptoms.</p><p><b>METHOD</b>Using a cluster random sampling method, 5 elementary schools and 10 kindergartens were randomly selected from each district of Shenyang, and all children from the selected schools were recruited in this survey. The information about the children's respiratory diseases, conditions of pets ownership and ETS exposure were collected by an international standard questionnaire from American Thoracic Society.</p><p><b>RESULT</b>A total of 9679 questionnaires were distributed to all the students enrolled in the selected schools, and 8798 completed questionnaires were collected with a response rate of 90.9%. Finally, 8733 questionnaires were used for further analysis. The results showed that the number of the patients and the prevalence of persistent cough, persistent phlegm, doctor-diagnosed asthma, current asthma, wheeze, and allergic rhinitis in children were 835 (9.57%), 366 (4.42%), 559 (6.40%), 215 (2.46%), 229 (2.62%), 397 (4.55%), respectively. After controlling for the effects of age, gender and other confounding factors, the results from the multivariate unconditional logistic regression analysis showed that either pet ownership or the ETS exposure significantly increased the risk of prevalence of respiratory diseases and symptoms in children. Compared with control group children, only the prenatal exposure to passive smoking or domestic pets made the risk of children with allergic rhinitis increased respectively 34% (OR = 1.34, 95%CI = 0.99 - 1.80) and 106% (OR = 2.06, 95%CI = 1.28 - 3.31), while the exposure of these two factors made the risk of children with allergic rhinitis increased 376% (OR = 4.76, 95%CI = 2.65 - 8.85), compared with the separate effect, the range of increase was 2.5 times.There was a significant interaction between pet ownership and ETS exposure on persistent cough, persistent phlegm, and allergic rhinitis in children, whereas, the combined effects of these two factors on doctor-diagnosed asthma, current asthma, and wheeze was approximately as expected on the basis of their independent effects on an additive scale.</p><p><b>CONCLUSION</b>This study provides evidence that pet ownership and ETS exposure increases the risk of respiratory diseases and symptoms in children, and there was a significant interaction effects between these two factors on some respiratory diseases and symptoms.</p>

Effects of indoor air pollution on asthma and asthma-related symptoms among children in Shenyang city / 中华预防医学杂志

<p><b>OBJECTIVE</b>To study the effects of indoor air pollution and individual susceptible factors on prevalence of children's asthma and asthma-related symptoms in Shenyang city.</p><p><b>METHODS</b>On April, 2007, 8733 Han children who were under age of 12 and lived for more than 2 years in Shenyang city, were selected from five administrative areas (one primary school and two kindergartens for each area) through cluster random sampling method. Information on children's general condition, asthma and related symptoms (including stridor, stridor symptoms, persistent cough, persistent phlegm), indoor air pollution, and susceptibility history were obtained by a standard questionnaire from the American Thoracic Society. The effects of indoor air pollution on asthma and asthma-related symptoms was analyzed through χ(2) test. Logistic regression was used to research the effects of risk factors on the prevalence of asthma and asthma-related symptoms of both susceptible and non-susceptible children.</p><p><b>RESULTS</b>Among the 8733 subjects, 4420 (50.6%) were boy and 4313 (49.4%) were girl, with the age of (8.08 ± 2.88) years old. The prevalence of asthma, current asthma, cough, persistent phlegm, stridor and stridor symptom were 6.4% (559 cases), 2.5% (215 cases), 9.6% (836 cases), 4.4% (386 cases), 17.5% (1524 cases) and 2.6% (229 cases) respectively. The prevalence of asthma the boys and girls were among 7.1% (313 cases) and 5.7% (246 cases) (χ(2) = 6.916, P < 0.05); and stridor symptom for them were 19.2% (850 cases), 15.6% (674 cases) (χ(2) = 19.678, P < 0.05), respectively. Passive smoking before two years old, house decoration and pet were related to asthma of children, and there was significant difference between the two groups. The prevalence of asthma of exposed children were 7.7% (312 cases), 9.5% (159 cases), 8.0% (270 cases), 9.0% (114 cases), respectively. Compared with the non-exposed children who had asthma, the prevalence of asthma were 5.7% (400 cases), 5.4% (289 cases), 6.0% (445 cases), the value of χ(2) were 33.646, 23.944 and 16.527 respectively (all P values < 0.05). Children who had family history of asthma, family history of allergy and allergy history were also related with asthma, the prevalence of asthma were 17.3% (106 cases), 13.1% (85 cases), 22.0% (147 cases), compared with the non-exposed children who had asthma, the prevalence of asthma were 5.5% (453), 5.9% (474), 5.1% (412), and there was significant difference between the two groups, the value of χ(2) were 130.522, 59.929 and 293.997, respectively (all P values < 0.05). Logistic regression analysis showed that passive smoking (OR = 1.7, 95%CI: 1.2 - 2.4), house decoration (OR = 1.5, 95%CI: 1.1 - 1.9) and pet (OR = 1.6, 95%CI: 1.1 - 2.3) were statistically significant to asthma in non-susceptible children. While passive smoking (OR = 1.3, 95%CI: 1.0 - 1.7) and house decoration (OR = 1.4, 95%CI: 1.1 - 1.7) were increased the risk of asthma.</p><p><b>CONCLUSION</b>Indoor air pollution is a risk factor of children' s asthma. Family history of asthma and physical susceptible children are high risk to asthma, and susceptible children are easily influenced by other risk factors.</p>

The effects of breastfeeding on asthma and asthma related symptoms among children / 中华预防医学杂志

<p><b>OBJECTIVE</b>To evaluate the effect of breastfeeding on asthma and asthma related symptoms among children.</p><p><b>METHODS</b>Using a cluster random sampling method, 2 elementary schools and 1 kindergarten were randomly selected from each of the 5 districts of Shenyang, and a total of 10 elementary schools and 5 kindergartens were included, and 8733 children from the selected schools were recruited in this survey. The information about the type of feeding, living environment and respiratory diseases of the selected children from the time they were born was collected by an international standard questionnaire. Evaluating the effect of breastfeeding on asthma and asthma related symptoms (asthma, current asthma, current wheeze, persistent cough, persistent phlegm, and allergic rhinitis) by χ² test and logistic regression.</p><p><b>RESULTS</b>There were 8733 children involved in this study. The age was (8.00 ± 2.88) years old. There were 6830 breastfed children. The percentage of breastfed children was 78.21%. In breastfed children, the prevalence of asthma, persistent phlegm and allergic rhinitis were 6.12% (418/6830), 3.97% (271/6830), 4.17% (285/6830), respectively. In non-breastfed children, the prevalence of asthma, persistent phlegm and allergic rhinitis were 7.41% (141/1903), 6.04% (115/1903), 5.89% (112/1903), respectively. Compared to the non-breastfed children, the breastfed children had significantly lower prevalence (all P values < 0.05). After adjustment for 302 cases of atopy history of children's mother, the results showed that in breastfed children, the prevalence of asthma, persistent phlegm and allergic rhinitis were 14.69% (36/245), 4.08% (10/245), 7.35% (18/245), respectively. In non-breastfed children, the prevalence of asthma, persistent phlegm and allergic rhinitis were 33.33% (19/57), 14.04% (8/57), 17.54% (10/57), respectively. The breastfed children had statistically lower prevalence (all P values < 0.05). Multivariate analysis showed that breastfeeding was significantly associated with lower prevalence of asthma (OR = 0.78, 95%CI: 0.64 - 0.96), allergic rhinitis (OR = 0.72, 95%CI: 0.57 - 0.90), persistent cough (OR = 0.81, 95%CI: 0.69 - 0.96) and persistent expectoration (OR = 0.61, 95%CI: 0.48 - 0.76).</p><p><b>CONCLUSION</b>Breastfed children had lower prevalence of asthma and asthma related symptoms compared with non-breastfed children.</p>

Epidemiologic survey on the prevalence and distribution of childhood functional constipation in the northern areas of China: a population-based study / 中华流行病学杂志

Objective Functional constipation (FC) is a common complaint in childhood but the prevalence still remains unclear, the aim of this study was to explore the prevalence of FC in childhood in the northern parts of China. Methods A screening program on FC in childhood was carried out in 5 northern cities (Beijing, Tianjin, Shenyang, Changchun, Harbin) of China according to symptoms under the Rome Ⅲ criteria. Random clustered sampling of the inhabitants was carried out under stratification of cities, geographic zones, schools or nurseries.Sample size of each area was in proportion to the population of the area. The range of age was 4-14. All subjects under study were requested to fill in a questionnaire distributed by the teachers. The screening program was carried out immediately after a section survey was completed. All together, 20 000 questionnaires were distributed with 19 638 retrievals. According to the result of the screening, a small number of patients who met the criteria were further selected to undergo a detailed clinical examination in the hospital including laboratory examination, colonic transit time, defecography or/and barium enema, electromyologram and anorectal manometry to exclude organic disease of the colon. Simultaneously, a detailed questionnaire was requested to fill under the assistance of trained doctors or medical students.Prevalence of FC of the population was adjusted by the rate of correct diagnosis from the detailed study. Results The adjusted point prevalence of FC in 5 northern cities of China according to Rome Ⅲ criteria was 4.73% with higher prevalence rate of FC seen in the Beijing area (5.02%) than in other cities (4.82%, 4.76%, 4.27%, 4.40%, with P＜0.001 ). Male to female ratio was 1.26:1 with majority of the FC fell in the 4-6 year olds (5.76%). Conclusion FC appeared a common disorder in childhood in the northern parts of China which called for greater attention. Higher prevalence was noted in the age groups of 4-6.

Preliminary study on diagnostic standard of functional constipation in children from five cities in North China / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To explore the symptomatic criteria for diagnosis in children with functional constipation(FC) in North China.</p><p><b>METHODS</b>A screening program for FC in children was carried out in 5 northern cities (Beijing, Tianjin, Shenyang, Changchun, Harbin) of China according to symptoms using Rome III( criteria. Random clustered sampling of the inhabitants was carried out under stratification of city, region and school or kindergarten. Sample size of each area was in proportion to the population of the area. The range of age was 4-14. All the subjects were requested to fill in a questionnaire distributed by the teacher. The screening program was carried out immediately after a plot survey. A total of 20,000 questionnaires were distributed and 19,638 retrieved. According to the result of the screening, a small number of patients who fulfilled the criteria were further selected to undergo detail clinical examinations in the hospital including laboratory examination, colonic transit time, defecography or/and barium enema, electromyogram and anorectal manometry to exclude organic disease of the colon. A detailed questionnaire was filled in with the assistance from a trained doctor or a medical student. Potential risk factors and the relative symptoms were explored by comparing frequencies between FC group and non-FC group using χ2 and Logistic analysis.</p><p><b>RESULTS</b>Eighteen symptoms (defecation less than 3 times per week, dry hard sausage-shape stool, difficulty in defecation, abdominal pain, nausea and vomiting, etc) could exist in control group, but FC group had a higher frequency. The difference was statistically significant. Multivariable stepwise logistic regression analysis showed that defecation less than 3 times per week, hard sausage-shape feces, difficulty in defecation, and the need for laxative were associated with FC. The absence of other symptoms had no influence on diagnosis of FC. The sensitivity, specificity and diagnostic accuracy of symptomatic standard diagnostic test based on Rome III( criteria in FC children showed that ≥2 items had the best diagnostic accuracy but moderate sensitivity and specificity.</p><p><b>CONCLUSION</b>The symptomatic criteria for FC diagnosis in children are suggested as follows: (1) defecation frequency less than 3 times per week; (2) dry, hard, sausage-shape stool in most defecation; (3) difficulty in most defecation; (4) use of medication or digital evacuation. FC can be considered when 2 of the above 4 criteria are met and the symptoms last at least 2 months.</p>