Toxocara seroprevalence and childhood asthma among Malaysian children

BACKGROUND: The larva of Toxocara spp., a common animal roundworm, may infect non-compatible hosts, causing a profound immunological reaction with marked eosinophil and IgE responses, not unlike in atopy. In this study, we determined the seroprevalence of Toxocara exposure in 66 asthmatic and 58 non-asthmatic children. METHODS: Exposure to Toxocara was determined by examining the serum samples of the children for specific IgG antibodies to L2 Toxocara larvae, using a commercially available diagnostic kit. RESULTS: There was no significant difference in the mean age, sex, social class, residence type and presence of domestic pets at home between the two children groups. Children with bronchial asthma were observed to have higher Toxocara seropositivity than that of the non-asthmatic controls (21.2 vs 8.6%, P=0.047). CONCLUSION: The observed relationship between exposure to Toxocara infection and bronchial asthma in Malaysian children warrants further evaluation. An understanding of any possible contribution to the pathogenesis of childhood asthma provides a potential avenue for prevention.     

Mixed handedness prevails among children and adolescents with infantile asthma and diabetes

Non-right handedness has been associated with allergic diseases and asthma. Infantile diabetes, too, has been associated with non-right handedness but, to date, data are more consistent on a link between left handedness and asthma than on diabetes. We surmised that mixed handedness, as an indicator of neurodevelopmental disturbance of brain laterality, rather than left handedness is more prevalent among children with asthma and diabetes mellitus. A total of 100 families with a child or an adolescent diagnosed with infantile asthma (n = 50) or diabetes mellitus type 1 (n = 50) attending the Paediatric Clinic of the ‘Brotzu’ Hospital in Cagliari (Italy) in 2006 agreed to participate in the study. The Annett Hand Preference Questionnaire was used to test handedness. Compared with 99 same-age and -sex controls, cases were marginally less likely to be right handed (71% vs. 86%; OR = 0.82, 95% CI = 0.54–1.25), and statistically more likely to be mixed handed (20% vs. 6%; OR = 3.30, 95% CI = 1.27–8.56) than controls: χ² = 8.84, d.f. = 2, p = 0.01. Children with asthma or diabetes did not differ from controls by season of birth; however, mixed-handed (n = 12, 46%) and left-handed (n = 6, 35%) children were statistically more likely to be born in winter as against the other seasons than those who were right handed (n = 36, 23%). Severity was also marginally related to the chance of being classified as non-right handed. People with a genetic predisposition to immune disorders could be more likely to have been negatively affected by infection and inflammation during fetal life, thus developing a deviation in handedness during neurodevelopment, as well as suffering the consequence of disordered immunity during childhood, such as allergic reactions (asthma) and immune-mediated damage to specific internal organs (diabetes type 1).     

Are oral contraceptive use and pregnancy complications risk factors for atopic disorders among offspring?

In utero programming of atopic manifestations has been suggested. We investigated the association between oral contraceptive (OC) use before, and complications during pregnancy (CDP) and asthma, along with other atopic manifestations. The study is based on neonates from Kingston and St Andrew, a geographic subcohort from the Jamaican Perinatal Morbidity, Mortality Survey conducted in 1986-1987. Information on OC use and CDP was extracted from maternal interviews and medical records. In a follow up in 1997-1998, via interviews with mothers, trained nurses collected information on asthma/wheezing, coughing, eczema, and hay fever. Data, specific to this paper, from birth and 11-12 yr of age was available for a total of 1040 of the 1720 members of the geographic subcohort. Using logistic regression, controlling for confounders, we estimated adjusted odds ratio (aOR) and corresponding 95% confidence intervals (CI). For asthma or wheezing, and coughing, aOR for OC use were 1.81 (95% CI: 1.25-2.61), and 2.72 (95% CI: 1.41-5.24), respectively. CDP was only shown to be a significant risk factor for hay fever. Additionally, a higher number of older siblings were protective for hay fever. The results suggest that asthma in childhood may be programmed in utero.     

The effects of birthweight and breastfeeding on asthma among children aged 1–5 years

Aim:   Asthma is a major cause of morbidity and mortality among children and has steadily increased in prevalence. The combined effect of birthweight and breastfeeding on childhood asthma remains unclear.
Methods:   In this study, we analysed a nationally representative sample of children aged 1–5 years from the National Health and Nutrition Examination Survey 1999–2002. Logistic regression was performed to examine the hypothesis whether birthweight and breastfeeding are independently associated with the prevalence of asthma after accounting for the complex sampling design. In addition, we sought to describe the relationship between birthweight and childhood asthma and to assess the potentially combined effect between birthweight and breastfeeding on asthma among children aged 1–5 years after considering the possible effects of social and environmental factors.
Results:   We found that birthweight (measured continuously) was inversely and linearly associated with the prevalence of childhood asthma (odds ratio (OR) = 0.80 per 1 kg increase in birthweight, 95% confidence interval (CI): 0.65–0.98). Using a categorical variable, low birthweight (LBW) was positively associated with childhood asthma (OR = 1.28, 95% CI: 0.81–2.68). Furthermore, we detected an interaction between birthweight and breastfeeding on childhood asthma. Breastfeeding had a strong protective effect on asthma among children with high birthweight (OR = 0.14, 95% CI: 0.04–0.43) while it had no significant effect on asthma among children with normal birthweight or LBW.
Conclusions:   The mechanisms underlying these relationships remain uncertain and warrant further explanation.     

Parental concern towards the use of inhaled therapy in children with chronic asthma

BACKGROUND: Parental attitudes towards the use of inhaled therapy in children with chronic asthma influence treatment adherence and outcome. In the present study, we evaluated the perceptions and concerns of parents of children with chronic asthma towards inhaled therapy. METHODS: A self-administered standard questionnaire was distributed to parents of children attending the Paediatric Asthma Clinic. All these children required inhaled steroids for treatment. RESULTS: One-hundred and twelve of 170 parents (66%) surveyed were concerned with inhaled therapy. The most common concern with its use was medication side effects (91%), followed by 'inhaler dependency' (86%), cost of the inhaler (34%) and difficulty in using the inhaler (15%). Parental perception that the oral route was superior to the inhaled route, preference for the oral route for asthma prophylaxis and a higher steroid dose required for prophylaxis were more likely to be associated with concerns towards inhaled therapy. More importantly, these children were also more likely to miss > 25% of their prescribed doses of inhaled steroids (46 vs 22% in the group concerned about inhaled therapy compared with the group that was not concerned, respectively; P = 0.007) and had a higher mean number of nebulization treatments in the last year (3.2 +/- 2.9 vs 1.8 +/- 1.3 in the group concerned about inhaled therapy compared with the group that was not concerned, respectively; P = 0.01). CONCLUSIONS: A significant proportion of parents whose children were on inhaled prophylaxis had concerns towards the use of inhaled therapy. Parental concern towards inhaled therapy appeared to increase the problem of non-adherence to treatment. Education for these parents will need to be addressed to improve asthma management in our patient population.     

The prevalence of respiratory symptoms and asthma among school children in three different areas of Norway

The role of exposure to ambient air pollution has been a topic of interest as a potential risk factor for respiratory symptoms and asthma. We expected that the prevalence rates would vary in Norway between the capital, Oslo, the mountainous area Hallingdal and the industrial area Odda. Surveys were conducted in school children, aged 6-16 years, in; Oslo (n=2577), Hallingdal (n=1177) and Odda (n=831). The parent-reported prevalence of wheeze in past year was almost similar in Oslo (13. 1 (95% CI 11. 7-14. 5)) and Upper Hallingdal (14. 2 (13. 1–15. 3)), but lower in Odda (9. 0 (7. 0–11. 0)). The findings for severe respiratory symptoms were almost equal. The age patters within each area differed. The risk of wheeze ever (p < 0.001) and wheeze in past year (p=0.04) decreased with increasing age in Odda, while there was an increase in the risk of exercise induced wheeze in Oslo (p=0.02) and Hallingdal (p < 0.001). The lifetime prevalence of asthma was lowest in Odda (5. 4 (3. 8–7. 0)) compared to Oslo (9. 4 (8. 2–10. 6)) and Hallingdal (8. 5 (6. 8–10. 2)). There was a positive association between physical activity and wheeze in past year. The results do not support the hypothesis that respiratory morbidity is more common in urban than rural areas, age and physical activity can influence the prevalence rates of respiratory symptoms in school children.     

咳嗽变异性哮喘与儿童慢性咳嗽

咳嗽变异性哮喘(CVA)是儿童慢性咳嗽的常见原因之一,咳嗽为唯一或主要的临床症状,存在气道反应性增高或呼气流量的变异率异常。支气管舒张剂对咳嗽治疗的有效性是该症的基本诊断条件,肺通气功能和气道高反应性检查则是诊断的关键方法。在临床上应注意CVA与其他疾病的鉴别。使用抗炎药物的早期干预,有利于预防典型哮喘的发生。     

儿童哮喘控制联合用药的选择

哮喘是儿童最常见的异质性慢性疾病,需要长期规律的治疗.哮喘发病机制复杂,多种环境因素同时作用,治疗更是复杂多样.目前,除了避免接触可能诱发哮喘的各种变应原和刺激物外,药物治疗仍然是最基本、最重要的方法.吸入糖皮质激素治疗是控制哮喘的基石,但总体说来单一糖皮质激素吸入治疗,哮喘控制仍然不佳,而加入第2种药物联合治疗可改善症状,达到很好的控制水平.联合治疗包括吸入糖皮质激素联合长效β2受体激动剂、联合白三烯受体拮抗剂以及氨茶碱等治疗.通过比较这些联合治疗用于儿童哮喘的有效性及安全性的研究,可找到最佳治疗途径.     

Indoor environmental risk factors and seasonal variation of childhood asthma

Seasonality of asthma may result from varying exposures. This cross‐sectional study was designed to examine the relationship between indoor environmental factors and seasonal childhood asthma. Study subjects were participants from the International Study of Asthma and Allergies in Childhood (ISAAC) in 2004, a population‐based surveillance, which included school children aged 6–15 yr in south Taiwan. Cases included 1725 children who experienced asthma symptoms in the past 12 months and the references consisted of 19,646 children who reportedly have no asthma history. By using a moving average and principal component analysis, asthmatic children were grouped into four asthma subtypes: winter, spring, summer/fall, and perennial. Multivariate logistic regression was used to evaluate the effect of indoor environmental factors on seasonality of childhood asthma. For all asthma prevalence, a peak occurred in the winter and a nadir appeared in summer. Contributing factors of asthma for children, regardless of seasonality, included younger age, parental atopy, maternal smoking during pregnancy, breast feeding, and perceived air pollution. After adjusted for salient risk factors, water damage was significantly associated with all subtypes of asthma. Presence of cockroaches was related to the summer/fall asthma (adjusted odds ratio [aOR] = 1.65, 95% confidence interval [CI] = 1.12–2.55). Visible mold on the walls was associated with an increased occurrence of winter and spring asthma (aOR = 1.53, 95% CI = 1.26–1.85 and aOR = 1.34, 95% CI = 1.10–1.62, respectively). Passive smoking was shown to be related to spring and summer/fall asthma. Water damage is a possible risk for childhood asthma year‐round. Cockroaches and visible mold on the walls may play essential roles for seasonality of childhood asthma in Taiwan. Plausible mechanisms and allergic effects should be further determined. Elimination of these allergens is necessary to help prevent the development of asthma.     

The drug treatment of asthma in children

Drug therapy provides a safe and effective way of controlling asthma in children. The appropriate medications combined with advice regarding modification of trigger factors where possible should allow the asthmatic child a normal lifestyle. The child and the parents need to understand the rationale for treatment, particularly with regard to preventive medications, and education is an important aspect of management. As many children improve with increasing age, treatment should be continually re-assessed with the aim of maintaining the patient on the minimal amount of medication that will keep the asthma under good control.