Infections, medication use, and the prevalence of symptoms of asthma, rhinitis, and eczema in childhood

Factors contributing to the diagnosis and onset prediction of perennial allergic rhinitis in high-risk children: A sub-analysis of the CHIBA study

BACKGROUND

This study aimed to clarify the diagnostic and predictive factors for perennial allergic rhinitis (PAR) onset in children by analyzing the results of the Chiba High-risk Birth Cohort for Allergy study, which examined newborns with a family history of allergies.

METHODS

Overall, 306 pregnant women were recruited. Their newborns were examined by otolaryngologists and pediatric allergists at 1, 2, and 5 years of age. Participants with clinical and laboratory data available at all consultation points were considered eligible.

RESULTS

Among 187 eligible participants, the prevalence rates of PAR were 2.1%, 4.3%, and 24.1% at 1, 2, and 5 years of age, respectively. AR-specific nasal local findings and eosinophils in nasal smear were observed in a substantial number of patients with PAR at 1 and 2 years of age. Factors present up to 2 years of age that were associated with PAR onset at 5 years of age, in descending order, were as follows: sensitization to house dust mites (HDM), nasal eosinophilia, and sensitization to cat dander. In 44 cases with HDM sensitization, nasal eosinophilia up to 2 years of age achieved a sensitivity of 76.0% and a specificity of 73.7% for predicting PAR onset at 5 years.

CONCLUSIONS

Rhinitis findings and nasal eosinophilia are useful auxiliary diagnostic items for pediatric PAR. Sensitization to HDM and nasal eosinophilia were the most influential factors associated with future PAR onset. A combination of these factors may facilitate the prediction of PAR onset.

Antibiotic exposure and adverse long-term health outcomes in children: a systematic review and meta-analysis

BACKGROUND

Antibiotics are among the most commonly used drugs in children. In addition to inducing antibiotic resistance, antibiotic exposure has been associated with long-term adverse health outcomes.

METHODS

A systematic search using PRISMA Guidelines to identify original studies reporting associations between antibiotic exposure and long-term adverse health outcomes in children. Overall pooled estimates of the odds ratios (ORs) were obtained using fixed or random-effects models.

RESULTS

We identified 160 observational studies investigating 21 outcomes in 22,103,129 children. Antibiotic exposure was associated with an increased risk of atopic dermatitis (OR 1.40, 95% confidence interval (CI) 1.30-1.52, p<0.01), allergic symptoms (OR 1.93, 95%CI 1.66-2.26, p<0.01), food allergies (OR 1.35, 95%CI 1.20-1.52, p<0.01), allergic rhinoconjunctivitis (OR 1.66, 95%CI 1.51-1.83, p<0.01), wheezing (OR 1.81, 95%CI 1.65-1.97, p<0.01), asthma (OR 1.96, 95%CI 1.76-2.17, p<0.01), increased weight gain or overweight (OR 1.18, 95%CI 1.11-1.26, p<0.01), obesity (OR 1.21, 95%CI 1.05-1.40, p<0.01), juvenile idiopathic arthritis (OR 1.74, 95%CI 1.21-2.52, p<0.01), psoriasis (OR 1.75, 95%CI 1.44-2.11, p<0.01), autism spectrum disorders (OR 1.19, 95%CI 1.04-1.36, p=0.01) and neurodevelopment disorders (OR 1.29, 95%CI 1.09-1.53, p<0.01). Dose-response effects and stronger effects with broad-spectrum antibiotic were often reported. Antibiotic exposure was not associated with an altered risk of allergic sensitisation, infantile colic, abdominal pain, inflammatory bowel disease, celiac disease, type 1 diabetes, fluorosis, and attention deficit hyperactivity disorder.

CONCLUSION

Although a causal association cannot be determined from these studies, the results support the meticulous application of sound antibiotic stewardship to avoid potential adverse long-term health outcomes.

Paracetamol exposure and asthma: What does the evidence say? An overview of systematic reviews

OBJECTIVE

To conduct an umbrella review collating the existing evidence to determine whether there is an association between exposure of Paracetamol in-utero or in infancy and the development of childhood Asthma.

METHODS

In this review, systematic reviews with or without meta-analysis that reported the association between paracetamol and asthma in children were included. To identify relevant reviews, a search was performed in the electronic databases PubMed, the Cochrane Library, and Ovid MEDLINE. The protocol was registered in PROSPERO CRD42020156023. A separate search was conducted for primary studies from the last 5 years not yet included in systematic reviews reporting the association from January 2016 to March 2021.

RESULTS

The electronic searches identified 1966 review titles. After the removal of 493 duplicates, 1475 titles and abstracts were screened against the eligibility criteria. Full-text screening yielded six systematic reviews to be included in this review. The search for primary studies in the last 5 years yielded 1214 hits, out of which 5 studies were found suitable for inclusion. Three of them, that were not included in the systematic reviews, and have been summarised in this paper. The odds ratios (ORs) for the outcome of asthma in offspring of mothers with prenatal paracetamol consumption in any trimester were 1.28 (1.13-1.39) and 1.21 (1.02-1.44). For first trimester exposures, they were 1.12 (0.99-1.27), 1.39 (1.01-1.91), and 1.21 (1.14-1.28), for the second or third trimester, they were 1.49 (1.37-1.63) and 1.13 (1.04-1.23). For the third trimester only, the figure was 1.17 (1.04-1.31). Of the six reviews included, 1 had a low risk of bias, 2 had an unclear risk while 3 had a high risk of bias assessed using the ROBIS tool. There was no significant increased risk of asthma with early infancy exposure. The inter-study heterogeneity varied from I²  = 41% to I²  = 76% across reviews. In the primary studies, the OR for prenatal exposure ranged from 1.12 (0.25-4.98) to 4.66 (1.92-11.3) and for infancy exposure was 1.56 (1.06-2.30). All three included primary studies were adjudged to be of high quality using the Newcastle Ottawa scale.

CONCLUSIONS

There is a modest association between paracetamol exposure in-utero and the future development of asthma. Exposure in infancy has a less consistant association. All the studies done thus far are observational in nature, with their inherent biases. Further research, preferably randomized controlled trials are recommended to answer this pertinent question.

Maternal antibiotic exposure during pregnancy and the risk of allergic diseases in childhood: A meta-analysis

BACKGROUND

Increasing studies suggest that antibiotic exposure during pregnancy may increase the risk of childhood allergic diseases; however, controversy still exists. Thus, we conducted this meta-analysis to evaluate the association between antibiotic use during pregnancy and childhood asthma/wheeze, eczema/atopic dermatitis, and food allergy.

METHODS

CENTRAL, EMBASE, and PubMed were searched for studies up to July 20, 2020. Cohort studies and case-control studies that estimated the association of antibiotic exposure in pregnancy with the risk of childhood asthma/wheeze, eczema/atopic dermatitis, and food allergy were included. A random-effects model or fixed-effects model was used to calculate the pooled estimates. The quality of the included studies was assessed by the Newcastle-Ottawa Scale (NOS). Stata12.0 software was used to analyze the association through a meta-analysis.

RESULTS

A total of 26 studies were included in the meta-analysis. The results showed that maternal antibiotic exposure in pregnancy and the summary OR for the risk of childhood asthma/wheeze was 1.29 (95% CI = 1.16-1.43), the summary OR for eczema/atopic dermatitis was 1.62 (95% CI = 1.16-2.27), and the pooled OR for food allergy was 1.36 (95% CI = 0.94-1.96).

CONCLUSIONS

Our results indicated that maternal antibiotic use during pregnancy might increase the risk of asthma/wheeze and eczema/atopic dermatitis but not food allergy in children. Further studies with larger sample size and robust multivariable adjustment are needed to confirm our findings. Nevertheless, the appropriate use of antibiotics during pregnancy is incredibly important, and healthcare professionals should be selective when prescribing antibiotics for pregnant women.

Cumulative Evidence for Association of Acetaminophen Exposure and Allergic Rhinitis

BACKGROUND

Several studies have linked acetaminophen exposure to the risk of allergic rhinitis, with controversial results.

METHODS

A systematic search of PubMed, Embase, Cochrane Library, and Web of Science was conducted up to December 1, 2019. We included observational studies that examined the association between acetaminophen exposure and the risk of allergic rhinitis. Two reviewers independently extracted data and assessed study quality. Summary odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using random-effects meta-analysis.

RESULTS

Eighteen studies with 870,492 participants were included. Analysis showed that acetaminophen exposure was associated with an increased risk of allergic rhinitis (OR: 1.54, 95% CI: 1.41-1.69). Also, early exposure and exposure in the past year to acetaminophen was positively associated with risk of allergic rhinitis (OR: 1.34, 95% CI: 1.21-1.49 and OR: 1.74, 95% CI: 1.48-2.04, respectively). The risk of allergic rhinitis was greater for people who had acetaminophen exposure once per month over the past year (OR: 1.90, 95% CI: 1.60-2.26) compared to once per year (OR: 1.28, 95% CI: 1.11-1.48).

CONCLUSION

With our meta-analysis, we provide the evidence that exposure to acetaminophen is associated with an increased risk of allergic rhinitis. In addition, acetaminophen exposure in early life and acetaminophen exposure in the past year are positively associated with the risk of allergic rhinitis. Future research is needed to evaluate whether the association is causal.

Dose, Timing, and Type of Infant Antibiotic Use and the Risk of Childhood Asthma

BACKGROUND

Aspects of infant antibiotic exposure and its association with asthma development have been variably explored. We aimed to evaluate comprehensively and simultaneously the impact of dose, timing, and type of infant antibiotic use on the risk of childhood asthma.

METHODS

Singleton, term-birth, non-low-birth-weight, and otherwise healthy children enrolled in the Tennessee Medicaid Program were included. Infant antibiotic use and childhood asthma diagnosis were ascertained from prescription fills and healthcare encounter claims. We examined the association using multivariable logistic regression models.

RESULTS

Among 152 622 children, 79% had at least 1 antibiotic prescription fill during infancy. Infant antibiotic use was associated with increased odds of childhood asthma in a dose-dependent manner, with a 20% increase in odds (adjusted odds ratio [aOR], 1.20 [95% confidence interval {CI}, 1.19-1.20]) for each additional antibiotic prescription filled. This significant dose-dependent relationship persisted after additionally controlling for timing and type of the antibiotics. Infants who had broad-spectrum-only antibiotic fills had increased odds of developing asthma compared with infants who had narrow-spectrum-only fills (aOR, 1.10 [95% CI, 1.05-1.19]). There was no significant association between timing, formulation, anaerobic coverage, and class of antibiotics and childhood asthma.

CONCLUSIONS

We found a consistent dose-dependent association between antibiotic prescription fills during infancy and subsequent development of childhood asthma. Our study adds important insights into specific aspects of infant antibiotic exposure. Clinical decision making regarding antibiotic stewardship and prevention of adverse effects should be critically assessed prior to use during infancy.

Is preterm birth associated with asthma among children from birth to 17 years old? -A study based on 2011-2012 US National Survey of Children's Health

BACKGROUND

Preterm birth can interrupt lung development in utero and is associated with early life factors, which adversely affects the developing respiratory system. Studies on preterm birth and asthma risk are comparatively sparse and the results are not consistent.

METHODS

Multivariate analyses were performed on a cross-sectional data from the National Survey of Children's Health (NSCH) collected in 2011 to 2012. The NSCH was a nationally representative telephone survey sponsored by the Maternal and Child Health Bureau and conducted by the National Center for Health Statistics. A cross-sectional analysis using data from the US on 90,721 children was conducted to examine the relationship between preterm birth and asthma risk.

RESULTS

A total of 90,721 children under 17 years were included and 12% of the children were reported as preterm birth. The prevalence of diagnosed asthma was 15%, with a male to female ratio of 1.26:1. Children who were born preterm were 1.64 times (95% confidence interval: 1.45-1.84) more likely to develop asthma compared with those who were born term after controlling for confounders. Similarly, children who were low birth weight were 1.43 times (95% confidence interval: 1.25-1.63) more likely for asthma, and the odds ratio increased to 1.77 for those both preborn and low birth weight. Child's gender, race/ethnicity, age, family structure, family income levels, and household smoking were significantly associated with the odds of reported asthma.

CONCLUSIONS

Preterm birth was associated with increased risk of asthma among US children, supporting the notion that preterm birth may play a critical role in asthma development.

Antibiotics and autoimmune and allergy diseases: Causative factor or treatment?

The newborn infant emerges from an almost sterile environment into a world of bacteria. Bacteria colonize the infant's skin, lungs, and, of most importance, the gut. The process of bacterial colonization is coordinated, and each body niche acquires a unique composition of bacteria. In the gut, most bacteria belong to the Firmicutes and Bacteroidetes phyla, while Actinobacteria and Proteobacteria are far less abundant. Some of these bacteria possess strong immunoregulatory properties. Bacterial colonization is essential to skew the newborn's immune response away from the allergy-favoring Type-2 response towards a Type-1 immune response, which is essential for pathogen elimination. Imbalance between Type 1 and Type 2 responses, however, can promote autoimmunity. In addition, the microbiota shapes immune responses in adults. Autoimmune and allergic diseases are commonly associated with an altered composition of resident bacteria, which is known as dysbiosis. Perhaps the most common cause of disruption and alteration of the bacterial colonization of newborns is the use of antibiotics. It is not known whether the dysbiosis precedes or is the consequence of allergic and autoimmune disorders, and whether antibiotics can be a trigger for these disorders, depending on the type of antibiotic used and the maturity of immune system. In this review, we discuss the development of the microbiota in different body niches and their immunomodulatory potential. We evaluate the impact of antibiotics, both in mice and in humans, on microbial communities and how that may impact the development and manifestation of diseases through all stages of life: the prenatal period, childhood, and adulthood.

Early-life antibiotic exposure increases the risk of developing allergic symptoms later in life: A meta-analysis

This study systematically reviewed and quantified the relationship between exposure to antibiotics during the first 2 years of life and the risk of allergies/atopies including hay fever, eczema, food allergy, positive skin prick testing (SPT), or elevated allergen-specific serum/plasma immunoglobulin (Ig) E levels later in life. PubMed and Web of Science databases were searched for observational studies published from January 1966 through November 11, 2015. Overall pooled estimates of the odds ratios (ORs) were obtained using fixed or random-effects models. Early-life exposure to antibiotics appears to be related to an increased risk of allergic symptoms of hay fever, eczema, and food allergy later in life. The summary OR for the risk of hay fever (22 studies) was 1.23, 95% confidence interval (CI):1.13-1.34; I² : 77.0%. The summary OR for the risk of eczema (22 studies) was 1.26, 95% CI: 1.15-1.37; I² : 74.2%, and the summary OR for food allergy (3 studies) was 1.42, 95% CI: 1.08-1.87; I² : 80.8%. However, no association was found for antibiotics exposure early in life and objective atopy measurements including positive SPT or elevated allergen-specific serum/plasma IgE levels.

Role of combined prenatal and postnatal paracetamol exposure on asthma development: the Czech ELSPAC study

BACKGROUND

Prenatal and postnatal paracetamol exposure has been previously associated with asthma development in childhood in Western populations. We explore the association between prenatal and postnatal paracetamol exposure and asthma development in a Central European sample of Czech children, suggesting possible additive effect of the both exposures. Furthermore, since aspirin had been used more widely during study data collection in Central Europe, we also compared asthma development for those exposed to paracetamol and aspirin.

METHODS

We used data from 3329 children born in the 1990s as members of the prospective Czech European Longitudinal Study of Pregnancy and Childhood. Data about prenatal and postnatal paracetamol and aspirin exposure, and potential covariates were obtained from questionnaires completed by mothers. Data about incident asthma were obtained from paediatrician health records.

RESULTS

60.9% of children received paracetamol only postnatally, 1.5% only prenatally and 4.9% of children were exposed both during pregnancy and infancy. Prevalence of asthma in following population was 5% at 11 years. Being exposed to paracetamol both in prenatal and postnatal period was associated with asthma development (unadjusted OR 1.98, 95% CI 1.02 to 3.87). Being exposed only in the postnatal period was also significantly associated with increased risk of asthma. No association between prenatal exposure only and outcome was found. A higher but non-significant risk of asthma was observed for those whose mothers used paracetamol during pregnancy compared with those who used aspirin.

CONCLUSIONS

The main findings of this prospective birth cohort study add to previous observations linking prenatal and early postnatal paracetamol exposure to asthma development. However, the magnitude of effect is relatively modest, and therefore, we recommend paracetamol to remain the analgesic and antipyretic of choice throughout pregnancy and early childhood.

Association of Acetaminophen and Ibuprofen Use With Wheezing in Children With Acute Febrile Illness

BACKGROUND

Many infants and children receive acetaminophen and/or ibuprofen during febrile illness. Previously, some studies have linked acetaminophen and ibuprofen use to wheezing and exacerbation of asthma symptoms in infants and children.

OBJECTIVE

To assess whether acetaminophen or ibuprofen use are associated with wheezing in children presenting to the emergency department (ED) with febrile illness.

METHODS

This was a cross-sectional study of children who presented with fever to the pediatric ED between 2009 and 2013. The data were collected from questionnaires and from the children's medical files. Patients with wheezing in the ED were compared with nonwheezing patients. Associations between medication use and wheezing were assessed using univariate and multivariate analyses. The multivariate analysis adjusted for potential confounding variables (ie, age, atopic dermatitis, allergies, smoking, antibiotics use, etc) via propensity scores.

RESULTS

During the study period, 534 children admitted to the ED met our inclusion criteria, of whom 347 (65%) were included in the study. The use of acetaminophen was similar in children diagnosed with wheezing compared with those without wheezing (n = 39, 81.3%, vs n = 229, 82.7%, respectively). Ibuprofen use was significantly lower in children diagnosed with wheezing (n = 22, 52.4%, vs n = 168, 69.4%, respectively). In multivariate analysis, acetaminophen was not associated with a higher rate of wheezing during acute febrile illness (adjusted odds ratio [OR] = 0.76, 95% CI = 0.24- 2.39), whereas ibuprofen was associated with a lower risk of wheezing (adjusted OR = 0.36, 95% CI = 0.13-0.96).

CONCLUSIONS

Our study suggests that acetaminophen and ibuprofen are not associated with increased risk for wheezing during acute febrile illness.

Association between chronic acetaminophen exposure and allergic rhinitis in a rat model

Background:

Several population studies demonstrated an increased risk of allergic rhinitis in patients exposed to acetaminophen. However, no histologic studies have been conducted to assess the relationship between acetaminophen exposure and allergic rhinitis.

Objective:

In this study, we investigated the association between chronic acetaminophen exposure and the development of allergic rhinitis in a rat model.

Methods:

Ten female Sprague-Dawley rats were randomly assigned to either a control (n = 5) or an acetaminophen group (n = 5). The acetaminophen group received 200 mg/kg/day of acetaminophen suspended in yogurt via oral gavage for 120 days. The control group received only the yogurt vehicle. Allergic behavioral responses, including nose rub, eye rub, ear scratching, and neck and/or face scratching, were quantified. The rats were killed, and the noses were harvested. The portion of the nose, including the nasal septum and the inferior turbinates, was embedded in paraffin, sectioned, and stained with hematoxylin and eosin to quantify the inflammatory infiltrate.

Results:

The average number of allergic responses per animal was 13.2 in the acetaminophen group versus 6.2 in the control group (p = 0.032). All the rats in the acetaminophen group (100%) had mast cells infiltrating the lamina propria of the inferior turbinate, whereas mast cells were detected in only 40% of the animals in the control group. The average number of mast cells per animal in the acetaminophen group was 134 versus 21 in the control group (p = 0.048).

Conclusions:

Our study was the first to demonstrate a histologic association between chronic exposure to acetaminophen and rhinitis. Further research to elucidate the mechanism that underlies these findings is necessary.

Early-life antibiotic use is associated with wheezing among children with high atopic risk: a prospective European study

BACKGROUND

Little is known about the relationship between antibiotic use and asthma in the children with a higher risk of allergic sensitization. We examine the association between the use of specific therapeutic antibiotics in the first year of life and development of wheezing by 36 months among children with a higher risk of allergic sensitization.

METHODS

A multi-center prospective cohort study was conducted among children at high risk for allergic sensitization. A validated questionnaire was used to prospectively collect information on antibiotic use and potential risk factors for wheezing from parents or guardians of 606 children from three European countries at 6, 12, 24 and 36 months of age. Multivariate linear and logistic regression models were used to adjust for potential confounders and effect modifiers and to estimate the association of antibiotic use with the development of early childhood wheezing.

RESULTS

Of the antibiotics assessed, only macrolide use in the first year of life was associated with increasing risk for wheezing by 36 months, after adjusting for gender, socioeconomic status, breast feeding >6 months, tobacco smoke exposure, family history of asthma, and respiratory infection (RR = 1.09; 95% CI 1.05-1.13). To avoid a bias by indication, we analyzed children with and without respiratory infection separately. Similar associations were observed for macrolides use in children who had no respiratory infection.

CONCLUSIONS

In European children with a familial risk for allergic sensitization, we found a positive association between macrolide use in the first year of life and wheezing until 36 months old which was independent of the effect of respiratory infection.

Combined and alternating paracetamol and ibuprofen therapy for febrile children

BACKGROUND

Health professionals frequently recommend fever treatment regimens for children that either combine paracetamol and ibuprofen or alternate them. However, there is uncertainty about whether these regimens are better than the use of single agents, and about the adverse effect profile of combination regimens.

OBJECTIVES

To assess the effects and side effects of combining paracetamol and ibuprofen, or alternating them on consecutive treatments, compared with monotherapy for treating fever in children.

SEARCH METHODS

In September 2013, we searched Cochrane Infectious Diseases Group Specialized Register; Cochrane Central Register of Controlled Trials (CENTRAL); MEDLINE; EMBASE; LILACS; and International Pharmaceutical Abstracts (2009-2011).

SELECTION CRITERIA

We included randomized controlled trials comparing alternating or combined paracetamol and ibuprofen regimens with monotherapy in children with fever.

DATA COLLECTION AND ANALYSIS

One review author and two assistants independently screened the searches and applied inclusion criteria. Two authors assessed risk of bias and graded the evidence independently. We conducted separate analyses for different comparison groups (combined therapy versus monotherapy, alternating therapy versus monotherapy, combined therapy versus alternating therapy).

MAIN RESULTS

Six studies, enrolling 915 participants, are included. Compared to giving a single antipyretic alone, giving combined paracetamol and ibuprofen to febrile children can result in a lower mean temperature at one hour after treatment (MD -0.27 °Celsius, 95% CI -0.45 to -0.08, two trials, 163 participants, moderate quality evidence). If no further antipyretics are given, combined treatment probably also results in a lower mean temperature at four hours (MD -0.70 °Celsius, 95% CI -1.05 to -0.35, two trials, 196 participants, moderate quality evidence), and in fewer children remaining or becoming febrile for at least four hours after treatment (RR 0.08, 95% CI 0.02 to 0.42, two trials, 196 participants, moderate quality evidence). Only one trial assessed a measure of child discomfort (fever associated symptoms at 24 hours and 48 hours), but did not find a significant difference in this measure between the treatment regimens (one trial, 156 participants, evidence quality not graded). In practice, caregivers are often advised to initially give a single agent (paracetamol or ibuprofen), and then give a further dose of the alternative if the child's fever fails to resolve or recurs. Giving alternating treatment in this way may result in a lower mean temperature at one hour after the second dose (MD -0.60 °Celsius, 95% CI -0.94 to -0.26, two trials, 78 participants, low quality evidence), and may also result in fewer children remaining or becoming febrile for up to three hours after it is given (RR 0.25, 95% CI 0.11 to 0.55, two trials, 109 participants, low quality evidence). One trial assessed child discomfort (mean pain scores at 24, 48 and 72 hours), finding that these mean scores were lower, with alternating therapy, despite fewer doses of antipyretic being given overall (one trial, 480 participants, low quality evidence) Only one small trial compared alternating therapy with combined therapy. No statistically significant differences were seen in mean temperature, or the number of febrile children at one, four or six hours (one trial, 40 participants, very low quality evidence). There were no serious adverse events in the trials that were directly attributed to the medications used.

AUTHORS' CONCLUSIONS

There is some evidence that both alternating and combined antipyretic therapy may be more effective at reducing temperatures than monotherapy alone. However, the evidence for improvements in measures of child discomfort remains inconclusive. There is insufficient evidence to know which of combined or alternating therapy might be more beneficial.Future research needs to measure child discomfort using standardized tools, and assess the safety of combined and alternating antipyretic therapy.

Factors associated with atopy in toddlers: a case-control study

In this case-control study the association between the approaches used to feed infants, together with known family and environmental factors, and the occurrence of atopic illness in toddlers between the ages of 4 months to 3 years in Hong Kong was examined. A total of 206 subjects were recruited from April to June of 2014. The results obtained by binary logistic regression indicated that atopy is associated with boys (OR 2.072, CI 1.089-3.941), the maternal use of antibiotics in utero or while breast feeding (OR 2.276, CI 1.151-4.504), the later commencement of mixed feeding (OR 2.497, CI 1.025-6.082), breast feeding exclusively for 3 months (OR 1.972, CI 1.009-3.857), and having a mother who was diagnosed with eczema (OR 4.510, CI 1.764-11.530). Although an exclusive reliance on breast feeding has been shown to be predictive of atopy among toddlers, the positive qualities of breast milk cannot be ignored. A further study of the contents and nutritional values of breast milk is warranted.

Prenatal and infant exposure to acetaminophen and ibuprofen and the risk for wheeze and asthma in children

BACKGROUND

Several studies have reported an association between use of over-the-counter antipyretics during pregnancy or infancy and increased asthma risk. An important potential limitation of these observational studies is confounding by indication.

OBJECTIVES

We investigated the association of antipyretic intake during pregnancy and during the first year of life (infancy) with asthma-related outcomes before and after controlling for early-life respiratory tract infections.

METHODS

We included 1490 mother-child pairs in Project Viva, a longitudinal prebirth cohort study. We categorized prenatal acetaminophen exposure as the maximum intake (never, 1-9 times, or ≥10 times) in early pregnancy or midpregnancy and ibuprofen intake as presence or absence in early pregnancy. We expressed intake of antipyretics in infancy as never, 1 to 5 times, 6 to 10 times, or more than 10 times. We examined the associations of acetaminophen and ibuprofen (per unit increase in exposure category) during pregnancy and infancy with wheeze, asthma, and allergen sensitization in early childhood (3-5 years of age, n = 1419) and midchildhood (7-10 years of age, n = 1220).

RESULTS

Unadjusted models showed an increased asthma risk in early childhood for higher infant acetaminophen (odds ratio [OR], 1.21; 95% CI 1.04-1.41) and ibuprofen (OR, 1.35; 95% CI, 1.19-1.52) intake. Controlling for respiratory tract infections attenuated estimates for acetaminophen (OR, 1.03; 95% CI, 0.88-1.22) and ibuprofen (OR, 1.19; 95% CI, 1.05-1.36). Prenatal acetaminophen was associated with increased asthma (OR, 1.26; 95% CI, 1.02-1.58) in early childhood but not midchildhood.

CONCLUSIONS

Adjustment for respiratory tract infections in early life substantially diminished associations between infant antipyretic use and early childhood asthma. Respiratory tract infections should be accounted for in studies of antipyretics and asthma to mitigate bias caused by confounding by indication.

The association between acetaminophen and asthma: is there anything to learn from the upper airways?

PURPOSE OF REVIEW

To examine the literature evidence for the association between acetaminophen (paracetamol) use and development of rhinitis.

RECENT FINDINGS

Increased use of acetaminophen (paracetamol) as the favored antipyretic during pregnancy and infancy has been hypothesized to be a risk factor for the development of asthma. There is a paucity of well designed birth cohort studies to examine paracetamol as a risk factor in the development of rhinitis. Confounding by antibiotic use, viral infections, and recall bias are problematic for many of the studies that are published.

SUMMARY

Prospective birth cohorts need to dedicate sufficient time and research personnel to adequately assess paracetamol exposure as a primary variable of interest rather than as an incidental exposure variable collected during routine questionnaire administration.

Does early life exposure to antibiotics increase the risk of eczema? A systematic review

A number of studies have suggested that early life exposure to antibiotics can lead to an increased risk of developing eczema. This systematic review and meta-analysis of observational studies, involving children or young adults aged 0-25 years, assessed the impact of antibiotic exposure either in utero or during the first 12 months of life on subsequent eczema risk. Twenty studies examined the association between prenatal and/or postnatal exposure to antibiotics and development of eczema. The pooled odds ratio (OR) for the 17 studies examining postnatal antibiotic exposure was 1.41 [95% confidence interval (CI) 1.30-1.53]. The pooled OR for the 10 longitudinal studies was 1.40 (95% CI 1.19-1.64), compared with a pooled OR of 1.43 (95% CI 1.36-1.51) for the seven cross-sectional studies. There was a significant dose-response association, suggesting a 7% increase in the risk of eczema for each additional antibiotic course received during the first year of life [pooled OR 1.07 (95% CI 1.02-1.11)]. Finally, the pooled OR for the four studies relating to antenatal exposure was 1.30 (95% CI 0.86-1.95). We conclude that exposure to antibiotics in the first year of life, but not prenatally, is more common in children with eczema.

Risk factors for eczema in infants born in Cuba: a population-based cross-sectional study

Background

There is a concern that allergic disease in childhood is higher than expected in Cuba. The aim of this study was to determine the risk factors for eczema of infants aged 12–15 months living in Havana.

Methods

We used a cross-sectional epidemiological study design. Data on eczema symptoms and a wide range of lifestyle factors were collected by researcher administered questionnaires.

Results

Data were collected on 1956 children (96% response rate), of whom 672 (34%) were reported as having had eczema. Independent risk factors for eczema included young maternal age (adjusted odds ratio (OR) 0.98 per additional year of age; 95% confidence interval (CI) 0.97-0.99), child’s weight (OR 1.13 per additional kg; 95% CI: 1.03-1.25), insect sting allergy (OR 2.11; 95% CI: 1.33-3.35), rodents in the home (OR 1.39; 95% CI: 1.10-1.76), attendance at childcare facilities (OR 1.34: 95% CI: 1.05-1.70) and self-reported mould in the home (OR 1.23; 95% CI: 1.07-1.41). Infant exposure to paracetamol was associated with an increased risk of eczema even after adjustment for wheeze (OR 1.22; 95% CI: 1.03-1.46).

Conclusion

Despite a very different culture and environment, the consistency of these findings with those from more economically developed countries suggests potential causal associations. The association with paracetamol, even after adjustment for wheeze, suggests that intervention studies are required in young infants, to ascertain if this commonly used anti-pyretic medication increases allergic disease.

Does maternal diet during pregnancy and lactation affect outcomes in offspring? A systematic review of food-based approaches

OBJECTIVES

The aim of this study was to investigate the relationship between maternal diet during pregnancy and lactation and development of atopic disorders in childhood.

METHODS

We included studies published up to August 2011 that assessed food-based maternal dietary interventions or that examined associations between maternal dietary intake during pregnancy and/or lactation and allergic outcomes (eczema, asthma, hay fever, and sensitization) in their children.

RESULTS

We included 42 studies (>40 000 children): 11 intervention studies (including 7 randomized control trials), 26 prospective cohort studies, 4 retrospective cohort studies, and 1 case-control study. In the randomized control trials, no significant difference was noted overall in the prevalence of eczema and asthma in the offspring of women on diets free from common food allergens during pregnancy. The prospective cohorts investigated a large number of potential associations, but reported few significant associations between maternal dietary intake and development of allergy. Maternal diets rich in fruits and vegetables, fish, and foods containing vitamin D and Mediterranean dietary patterns were among the few consistent associations with lower risk for allergic disease in their children. Foods associated with higher risk included vegetable oils and margarine, nuts, and fast food.

CONCLUSION

This review did not find widespread or consistent links between mothers' dietary intake and atopic outcomes in their children. However, maternal consumption of Mediterranean dietary patterns, diets rich in fruits and vegetables, fish, and vitamin D-containing foods were suggestive of benefit, requiring further evaluation.

Epidemiology of Respiratory Allergies and Asthma

Asthma has puzzled and confused physicians from the time of Hippocrates to the present day. The word “asthma” comes from a Greek word meaning “panting” (Keeney 1964), but reference to asthma can also be found in ancient Egyptian, Hebrew, and Indian medical writings (Ellul-Micallef 1976; Unger and Harris 1974). There were clear observations of patients experiencing attacks of asthma in the second century and evidence of disordered anatomy in the lung as far back as the seventeenth century (Dring et al. 1689).

Antibiotic exposure in the first two years of life and development of asthma and other allergic diseases by 7.5 yr: a dose-dependent relationship

BACKGROUND

Antibiotic use in infancy disrupts gut microflora during a critical period for immune system development. It is hypothesized that this could predispose to the development of allergic diseases. We investigated the associations of antibiotic use in the first 2 yr of life with the development of asthma, eczema or hay fever by age 7.5 yr in a longitudinal birth cohort.

METHODS

Subjects were 4952 children from the Avon Longitudinal Study of Parents and Children (ALSPAC). Child antibiotic use and asthma, eczema and hay fever symptoms were maternally reported. Atopy was assessed by skin prick tests at age 7.5 yr. The total number of antibiotic courses was considered as the main exposure. Data were analysed using multivariate logistic regression.

RESULTS

Children reported to have taken antibiotics during infancy (0-2 yr) were more likely to have asthma at 7.5 yr (OR 1.75, 95% CI 1.40-2.17), and the odds (OR, [95% CI]) increased with greater numbers of courses: once 1.11 [0.84-1.48]; twice 1.50 [1.14-1.98]; three times 1.79 [1.34-2.40]; four times or more 2.82 [2.19-3.63]. Increased antibiotic use was also associated with higher odds of eczema and hay fever but not atopy. The effect appeared to be associated with cumulative rather than a critical period of exposure during the first 2 yr.

CONCLUSIONS

A robust and dose-dependent association was found between antibiotic use in the first 2 yr of life and asthma at age 7.5 yr but did not appear to be mediated through an association with atopy.

Combined and alternating paracetamol and ibuprofen therapy for febrile children

BACKGROUND

Health professionals frequently recommend fever treatment regimens for children that either combine paracetamol and ibuprofen or alternate them. However, there is uncertainty about whether these regimens are better than the use of single agents, and about the adverse effect profile of combination regimens.

OBJECTIVES

To assess the effects and side effects of combining paracetamol and ibuprofen, or alternating them on consecutive treatments, compared with monotherapy for treating fever in children.

SEARCH METHODS

In September 2013, we searched Cochrane Infectious Diseases Group Specialized Register; Cochrane Central Register of Controlled Trials (CENTRAL); MEDLINE; EMBASE; LILACS; and International Pharmaceutical Abstracts (2009-2011).

SELECTION CRITERIA

We included randomized controlled trials comparing alternating or combined paracetamol and ibuprofen regimens with monotherapy in children with fever.

DATA COLLECTION AND ANALYSIS

One review author and two assistants independently screened the searches and applied inclusion criteria. Two authors assessed risk of bias and graded the evidence independently. We conducted separate analyses for different comparison groups (combined therapy versus monotherapy, alternating therapy versus monotherapy, combined therapy versus alternating therapy).

MAIN RESULTS

Six studies, enrolling 915 participants, are included.Compared to giving a single antipyretic alone, giving combined paracetamol and ibuprofen to febrile children can result in a lower mean temperature at one hour after treatment (MD -0.27 °Celsius, 95% CI -0.45 to -0.08, two trials, 163 participants, moderate quality evidence). If no further antipyretics are given, combined treatment probably also results in a lower mean temperature at four hours (MD -0.70 °Celsius, 95% CI -1.05 to -0.35, two trials, 196 participants, moderate quality evidence), and in fewer children remaining or becoming febrile for at least four hours after treatment (RR 0.08, 95% CI 0.02 to 0.42, two trials, 196 participants, moderate quality evidence). Only one trial assessed a measure of child discomfort (fever associated symptoms at 24 hours and 48 hours), but did not find a significant difference in this measure between the treatment regimens (one trial, 156 participants, evidence quality not graded).In practice, caregivers are often advised to initially give a single agent (paracetamol or ibuprofen), and then give a further dose of the alternative if the child's fever fails to resolve or recurs. Giving alternating treatment in this way may result in a lower mean temperature at one hour after the second dose (MD -0.60 °Celsius, 95% CI -0.94 to -0.26, two trials, 78 participants, low quality evidence), and may also result in fewer children remaining or becoming febrile for up to three hours after it is given (RR 0.25, 95% CI 0.11 to 0.55, two trials, 109 participants, low quality evidence). One trial assessed child discomfort (mean pain scores at 24, 48 and 72 hours), finding that these mean scores were lower, with alternating therapy, despite fewer doses of antipyretic being given overall (one trial, 480 participants, low quality evidence)Only one small trial compared alternating therapy with combined therapy. No statistically significant differences were seen in mean temperature, or the number of febrile children at one, four or six hours (one trial, 40 participants, very low quality evidence).There were no serious adverse events in the trials that were directly attributed to the medications used.

AUTHORS' CONCLUSIONS

There is some evidence that both alternating and combined antipyretic therapy may be more effective at reducing temperatures than monotherapy alone. However, the evidence for improvements in measures of child discomfort remains inconclusive. There is insufficient evidence to know which of combined or alternating therapy might be more beneficial.Future research needs to measure child discomfort using standardized tools, and assess the safety of combined and alternating antipyretic therapy.

Time trends, ethnicity and risk factors for eczema in New Zealand children: ISAAC Phase Three

BACKGROUND

Eczema is a common chronic disease which has significant morbidity and costs for children and their families. Phase One (1993) of the International Study of Asthma and Allergies in Childhood (ISAAC) found a high prevalence of symptoms of eczema in New Zealand.

OBJECTIVE

In Phase Three (2001-3) we aimed to answer these three questions: Is the prevalence of eczema changing over time?; Are there ethnic differences in prevalence?; and What are the risk factors for eczema?

METHODS

Five New Zealand centres participated in ISAAC Phases One and Three using the same methodology. Questionnaires about ethnicity, symptoms of eczema and environmental factors were completed by parents of 6-7 year olds (children) and self-completed by 13-14 year olds (adolescents). Prevalence and change per year were calculated by centre, ethnicity and gender. Prevalence differences between centres and associations with environmental factors were examined using logistic regression.

RESULTS

There was little change in prevalence over time for the children, and a decrease in prevalence for the adolescents. Prevalence was higher among Māori and even higher among Pacific participants than among European children. Positive associations with current eczema symptoms were found for both age groups for truck traffic in the street of residence, and current paracetamol consumption, and for children only, antibiotics or paracetamol in the 1st year of life. Inverse associations were found with residence in New Zealand less than 5 years, consumption of milk, seafood, and eggs, and presence of a dog in the home.

CONCLUSION

Eczema remains a significant problem, particularly for young Māori and Pacific New Zealanders in whom less recognition of eczema and poorer access to effective, sustained eczema management may be contributing factors. Reverse causation may explain all the environmental findings apart from truck traffic which is increasing in New Zealand.

Early life exposure to antibiotics and the risk of childhood allergic diseases: an update from the perspective of the hygiene hypothesis

The prevalence of allergic diseases has been growing rapidly in industrial countries during recent decades. It is postulated that growing up with less microbial exposure may render the immune system susceptible to a T helper type 2 (Th2)-predominant allergic response-also known as the hygiene hypothesis. This review delineates recent epidemiological and experimental evidence for the hygiene hypothesis, and integrates this hypothesis into the association between early life exposure to antibiotics and the development of allergic diseases and asthma. Several retrospective or prospective epidemiological studies reveal that early exposure to antibiotics may be positively associated with the development of allergic diseases and asthma. However, the conclusion is inconsistent. Experimental studies show that antibiotics may induce the Th2-skewed response by suppressing the T helper type 1 (Th1) response through inhibition of Th1 cytokines and disruption of the natural course of infection, or by disturbing the microflora of the gastrointestinal (GI) tract and therefore jeopardizing the establishment of oral tolerance and regulatory T cell immune responses. The hygiene hypothesis may not be the only explanation for the rapid increase in the prevalence of allergic diseases and asthma. Further epidemiological and experimental studies addressing the issue of the impact of environmental factors on the development of allergic diseases and the underlying mechanisms may unveil novel strategies for the prevention and treatment of allergic diseases in the future.

The case of drug causation of childhood asthma: antibiotics and paracetamol

AIM

The rising prevalence of bronchial asthma has led to world-wide efforts to understand and stem this development. Cross-sectional studies appear to show that early childhood use of antibiotics may be an important contributory factor, with paracetamol as an additional suspected cause. However, mounting evidence, which is reviewed here, points to various confounding factors as the major reasons for these reported associations.

METHODS

PubMed and EMBASE were systematically searched for studies on associations between antibiotics and/or paracetamol with asthma and/or wheezing, published up to November 2012. A total of 64 pertinent studies were identified, 35 focusing on antibiotics, 19 on paracetamol, and ten addressing both antibiotics and paracetamol, bringing the number of relevant datasets to 74.

RESULTS

Numerous studies were cross-sectional and made no adjustment for the indication of antibiotics or paracetamol; consequently, they were unable to dismiss possible confounding by indication. Where such adjustments could be performed (mostly in longitudinal studies), they substantially weakened or entirely eliminated the association with asthma or asthma surrogates present in the unadjusted data.

CONCLUSION

The weight of evidence of the collected studies in our review strongly suggests that the association of antibiotics with childhood asthma reflects various forms of bias, the most prominent of which is confounding by indication. Recent studies and meta-analyses support the same conclusion for paracetamol. Truly indicated antibiotics should not be withheld from infants or young children for fears they might develop asthma. Likewise, there is no sound reason to replace paracetamol as the preferred pain relief and fever medication in this age group.

Acetaminophen and asthma

Acetaminophen is a widely used medication for the treatment of pain and fever in children and pregnant women. There is substantial epidemiological evidence in adults and children that acetaminophen use is associated with asthma symptoms. There is also a considerable body of evidence that supports a modest but consistent association of acetaminophen use in pregnancy and early infancy with asthma in later childhood. This relationship is robust to adjustment for a large range of potential confounding factors and, in some studies, shows clear evidence of a dose-dependent association but the possibility of confounding by indication has remained a concern. However, the epidemiological evidence is now compelling and there is a clear need to establish causation so that appropriate advice and interventions can be developed for children at risk of asthma. This requires randomised trials of analgesics and antipyretics, including acetaminophen, in a variety of clinical settings.

The effect of a single dose of acetaminophen on airways response in children with asthma

Accumulating evidence suggests that the use of acetaminophen increases the risk of developing asthma and that its widespread use has contributed to the increasing prevalence of asthma.

STUDY DESIGN

To investigate the immediate effect of a single dose of acetaminophen on airways reactivity and inflammation in asthmatic and controls. A double blind placebo-controlled study was conducted on 42 asthmatic children and 21 healthy age-matched controls. Each participant received one oral dose of acetaminophen (15 mg/kg [160 mg/mL]) and one dose of a volume-matched placebo. Physical examination, spirometry results, and fractional exhaled nitric oxide levels were assessed before and 60 minutes following acetaminophen or placebo ingestion.

RESULTS

None of the studied variables showed any significant change after acetaminophen or placebo ingestion in either the asthmatic or the control groups.

CONCLUSIONS

One single dose of acetaminophen neither evokes a bronchoconstriction response nor an increase in airway inflammation in children with asthma.

The relationship between antibiotic therapy in early childhood and the symptoms of allergy in children aged 6-8 years - the questionnaire study results

INTRODUCTION

Studies based on the ISAAC questionnaire suggest a correlation between the use of antibiotics and the prevalence of asthma and allergy in children aged 6-7 years. The number of courses of antibiotic therapy is an important factor.

OBJECTIVES

To investigate the relationship between the use of antibiotics during the first years of life and the prevalence of allergy and asthma among children (aged 6-8 years) in the urban population of Poland.

MATERIALS AND METHODS

A survey-based study with a self-completed questionnaire. The respondents were parents of children aged 6-8 years living in Warszawa, Poland. 1461 completed questionnaires were collected.

RESULTS

Asthma was declared in 4.3% of the children. Wheezing and/or sibilant rhonchi within 12 months before the study was observed in 13.5% of the cases. Asthma medication was taken by 21.8% of the children. Allergic rhinitis was declared in 18.7% of the children. Problems with sneezing, rhinorrhea, and nasal congestion not associated with cold or fever were observed in 40.7% of the children. The analysis of the odds ratios between the use of antibiotics and the symptoms of allergic diseases revealed a clear correlation. The highest odds ratio was observed between the completion of over three courses of antibiotic therapy prior to the age of 12 months and the declaration of one of the following: asthma (OR = 5.59, 95% CI: 2.6-12.01), wheezing and/or sibilant rhonchi (OR = 4.68, 95% CI: 3.01-7.27) and taking medicines for breathlessness (OR = 5.12, 95% CI: 3.42-7.68).

CONCLUSIONS

There is a direct relationship between antibiotic use in the first 3 years of life and asthma and allergy symptoms in children aged 6-8 years old.

Interaction between IL13 genotype and environmental factors in the risk for allergic rhinitis in Korean children

BACKGROUND

The prevalence of allergic rhinitis (AR) is increasing worldwide. Allergic diseases develop in susceptible subjects when they are exposed to specific environmental factors.

OBJECTIVE

We analyzed changes in the prevalence of AR and identified genetic and environmental factors in early childhood that affect risk.

METHODS

We used the International Study of Asthma and Allergies in Childhood questionnaire to collect data on AR, allergies, and environmental exposures from 4554 elementary school students from 5 areas of Seoul, Korea, in 2008. We also obtained DNA from 1050 subjects from 1 area of Seoul for genotype analysis of IL13.

RESULTS

We identified genetic and environmental factors during infancy and early childhood that increased the risk for current AR (resulting in a diagnosis of AR and AR symptoms in the past 12 months) in elementary school-aged children. These included allergic disease in parents and antibiotic use in infants, allergic disease in parents and exposure of infants to mold, and allergic disease in parents and moving an infant to a newly built house. The risk of current AR also increased in subjects with GA or AA at nucleotide 2044 in IL13 who had been exposed to mold in the home during infancy (adjusted odds ratio, 3.27; 95% CI, 1.75-6.11) compared with subjects who had GG at this position and had not been exposed to mold (adjusted odds ratio, 3.27; 95% CI, 1.75-6.11).

CONCLUSION

The prevalence of AR is increasing in Korean children. Children with a family history of allergic disease and exposure to specific environmental risk factors during infancy are more likely to have AR. Children with GA or AA at IL13(+2044) are at increased risk for AR when exposed to mold in the home during the first year of life.

Is the asthma epidemic still ascending?

Asthma is a phenotypically heterogeneous disorder of multifactorial origins that affects 300 million people suffering from asthma and more than 250,000 asthma-related deaths each year. Although treatment for asthma has improved, its prevalence continues to increase, particularly in low and middle income countries, or in some ethnic groups in which prevalence was previously low. Observed spatio-temporal variations in the increased prevalence of asthma depend on exposure to environmental factors. Recently, several arguments are also in favor of the involvement of host susceptibility and stress in the observed increase of asthma prevalence. Further investigations are warranted to better understand mechanisms underlying asthma increase or stagnation.

Rhinoconjunctivitis prevalence and associated factors in school children aged 6-7 and 13-14 years old in Bogota, Colombia

OBJECTIVE

Allergic rhinitis is one of the most frequent chronic diseases among children. The objective of the study was to assess the prevalence of rhinoconjunctivitis and determine clinical, social and environmental associated factors, among school children aged 6-7 years and adolescents aged 13-14 years in Bogotá, Colombia.

METHODS

We used ISAAC (International Study of Asthma and Allergies in Childhood) phase III study methodology and questionnaire for design and data collection, and we did a secondary analysis of these data. The sample consisted of 3830 registers from adolescents between 13 and 14 years old and 3256 registers from children between 6 and 7 years.

RESULTS

The prevalence of rhinoconjunctivitis symptoms in the last year was 17.2% (95% CI, 15.9-18.5) in children vs. 24.9% (95% CI, 23.6-26.3) in adolescents. In both groups there was a female predominance in children (17.8% vs. 16.5%), and in the teenagers group (28.0% vs. 21.4%), though the differences were not statistically significant. The factors associated with rhinoconjunctivitis in the group of 6-7 years where: asthma [OR 3.9; (95% CI, 2.8-5.4)], atopic dermatitis [OR 2.3; (95% CI, 1.7-3.1)], use of acetaminophen in the last year [OR 2.6; (95% CI, 1.4-4.9)], use of antibiotics in the first year of live [OR 1.7; (95% CI, 1.3-2.3)], higher maternal education [OR 1.5; (95% CI, 1.0-2.3)] and cesarean delivery [OR 1.6; (95% CI, 1.2-2.1)]. Among the 13-14 year age-group, factors associated with rhinoconjunctivitis included: asthma [OR 2.6; (95% CI, 2.0-3.4)], atopic dermatitis [OR 1.8; (95% CI, 1.4-2.3)], use of acetaminophen in the last year [OR 1.8; (95% CI, 1.4-2.4)], consumption of fast-food three times or more per week [OR 1.5; (95% CI, 1.2-2.0), ever smoked [OR 1.4; (95% CI, 1.2-1.7)] and meat consumption was protective factor [OR 0.7; (95% CI, 0.5-0.9)].

CONCLUSION

In both studied groups, the estimated prevalence of rhinoconjunctivitis symptoms was relatively high. Future in-depth research is needed to assess the complex interactions between allergic rhinoconjunctivitis symptoms and social and environmental factors.

Effect of prenatal exposure to fine particulate matter and intake of Paracetamol (Acetaminophen) in pregnancy on eczema occurrence in early childhood

The goal of the study was to test the hypothesis that prenatal Paracetamol exposure increases the risk of developing eczema in early childhood and that this association may be stronger in children who are exposed in fetal period to higher concentrations of fine particulate matter (PM2.5). The study sample consisted of 322 women recruited from January 2001 to February 2004 in the Krakow inner city area who gave birth to term babies and completed 5-year follow-up. Paracetamol use in pregnancy was collected by interviews and prenatal personal exposure to PM2.5 over 48 h was measured in recruited women in the second trimester of pregnancy. After delivery, every three months in the first 24 months of the newborn's life and every 6 months later, a detailed standardized face-to-face interview on the infant's health was administered to each mother by trained interviewers. During the interviews at each of the study periods after birth, a history of eczema was recorded. The incident rate ratio (IRR) for frequency of eczema events over the follow-up was estimated from the Poisson regression model and the overall effect of main exposure variables on eczema was assessed by odds ratios (ORs) by the logistic model. The estimated relative risk of eczema occurring whenever in the follow-up was related significantly neither with prenatal Paracetamol nor higher PM2.5 exposure, however, their joint effect was significant (OR interaction term=6.04; 95%CI: 1.04-35.16). Of potential confounders considered in the analysis only damp/moldy home significantly increased the risk of eczema (OR=1.53; 95%CI: 1.14-2.05). In contrast, there was an inverse significant association between the presence of older siblings and eczema (OR=0.55; 95%CI: 0.35-0.84). The joint effect of the main exposure variables significantly increased frequency of eczema events (IRR=1.78, 95%CI: 1.22-2.61). In conclusion, the findings of the study suggest that Paracetamol use by mothers in pregnancy is not an independent risk factor for eczema in children, however, even very small doses of Paracetamol taken in pregnancy may contribute to the occurrence of allergic symptoms in early childhood if there is prenatal co-exposure to higher airborne fine particulate matter.

A review of non-pharmacological and pharmacological management of seasonal and perennial allergic conjunctivitis

Allergic eye disease encompasses a group of hypersensitivity disorders which primarily affect the conjunctiva and its prevalence is increasing. It is estimated to affect 8% of patients attending optometric practice but is poorly managed and rarely involves ophthalmic assessment. Seasonal allergic conjunctivitis (SAC) is the most common form of allergic eye disease (90%), followed by perennial allergic conjunctivitis (PAC; 5%). Both are type 1 IgE mediated hypersensitivity reactions where mast cells play an important role in pathophysiology. The signs and symptoms are similar but SAC occurs periodically whereas PAC occurs year round. Despite being a relatively mild condition, the effects on the quality of life can be profound and therefore they demand attention. Primary management of SAC and PAC involves avoidance strategies depending on the responsible allergen(s) to prevent the hypersensitivity reaction. Cooled tear supplements and cold compresses may help bring relief. Pharmacological agents may become necessary as it is not possible to completely avoid the allergen(s). There are a wide range of anti-allergic medications available, such as mast cell stabilisers, antihistamines and dual-action agents. Severe cases refractory to conventional treatment require anti-inflammatories, immunomodulators or immunotherapy. Additional qualifications are required to gain access to these medications, but entry-level optometrists must offer advice and supportive therapy. Based on current evidence, the efficacy of anti-allergic medications appears equivocal so prescribing should relate to patient preference, dosing and cost. More studies with standardised methodologies are necessary elicit the most effective anti-allergic medications but those with dual-actions are likely to be first line agents.

Parental administration of antipyretics to children with upper respiratory tract infections without consultation with a physician

Aim

To evaluate the administration of antipyretics to children with upper respiratory tract infections (URTI) by their parents or guardians without consultation with physicians, and compare epidemiological and clinical characteristics of patients who received antipyretics and of untreated patients.

Methods

A prospective observational study was performed in three pediatric clinics in Zagreb, Croatia, from March to June 2002. A total of 171 children aged from 2 to 14 years with symptoms and signs of URTI lasting more than 2 days and fever above 38°C lasting more than 2 days were included in the study. Data were collected on the usage of antipyretics, patients’ demographic and epidemiological characteristics, and clinical signs and symptoms.

Results

Antipyretics, predominantly paracetamol, were used in 29.8% of patients. Their usage was less frequent in children attending day-care centers (49% of treated and 70% of untreated children, P = 0.014) and in children with reiterated URTIs (33.3% of treated and 55.8% of untreated children, P = 0.008). However, it was more frequent in children with recent URTIs in the family (33.3% of treated and 7.5% of untreated children, P < 0.001). Overall, most clinical signs and symptoms of URTI were notably less pronounced in patients treated with antipyretics.

Conclusions

Antipyretics use correlated with less pronounced clinical signs and symptoms of infection, which indicates their anti-inflammatory activity, but also with negative effects such as lethargy. It is necessary to educate parents on the positive and negative aspects of antipyretics use and on the optimal choice of an antipyretic drug.

Prenatal or early-life exposure to antibiotics and risk of childhood asthma: a systematic review

CONTEXT

The increasing prevalence of childhood asthma has been associated with low microbial exposure as described by the hygiene hypothesis.

OBJECTIVE

We sought to evaluate the evidence of association between antibiotic exposure during pregnancy or in the first year of life and risk of childhood asthma.

METHODS

PubMed was systematically searched for studies published between 1950 and July 1, 2010. Those that assessed associations between antibiotic exposure during pregnancy or in the first year of life and asthma at ages 0 to 18 years (for pregnancy exposures) or ages 3 to 18 years (for first-year-of-life exposures) were included. Validity was assessed according to study design, age at asthma diagnosis, adjustment for respiratory infections, and consultation rates.

RESULTS

For exposure in the first year of life, the pooled odds ratio (OR) for all studies (N = 20) was 1.52 (95% confidence interval [CI]: 1.30-1.77). Retrospective studies had the highest pooled risk estimate for asthma (OR: 2.04 [95% CI: 1.83-2.27]; n = 8) compared with database and prospective studies (OR: 1.25 [95% CI: 1.08-1.45]; n = 12). Risk estimates for studies that adjusted for respiratory infections (pooled OR: 1.16 [95% CI: 1.08-1.25]; n = 5) or later asthma onset (pooled OR for asthma at or after 2 years: OR: 1.16 [95% CI: 1.06-1.25]; n = 3) were weaker but remained significant. For exposure during pregnancy (n = 3 studies), the pooled OR was 1.24 (95% CI: 1.02-1.50).

CONCLUSIONS

Antibiotics seem to slightly increase the risk of childhood asthma. Reverse causality and protopathic bias seem to be possible confounders for this relationship.

Wheezing and asthma may be enhanced by broad spectrum antibiotics used in early childhood. Concept and results of a pharmacoepidemiology study

One of the mechanisms supposed to explain the increasing prevalence of asthma, among children in particular, is the use of antibiotics because they may modify natural microbial exposure and development of the immune system in early childhood. The aim of this study is to investigate the association between the use of various classes of antibiotics (penicillin, cephalosporin and macrolide derivatives) in early childhood and the medical diagnosis of asthma or wheezing reported by mothers over the follow-up after adjustment for potential confounders and respiratory infections. In a population-based sample of 5-year-olds, a part of the ongoing birth cohort study, the standardized interviews on health outcomes, potential confounders (child's gender, maternal atopy, parity, prenatal and postnatal environmental tobacco smoke) and the use of antibiotics were gathered from mothers of 310 children. While the overall use of antibiotics during the early childhood was insignificantly associated with asthma (adjusted OR = 1.65, 95%CI: 0.93 - 2.93), the risk estimates were significant both for macrolide antibiotics (adjusted OR=2.14, 95%CI: 1.16-3.95) and cephalosporins (OR=1.98, 95%CI: 1.14-3.37). The significant excess in IRR (incident risk ratio) of wheezing episodes was related only to the use of macrolide antibiotics (adjusted IRR=1.91, 95%CI: 1.12-3.27). The use of other classes of antibiotics was found not to be associated with the medical diagnosis of asthma or wheezing episodes recorded in the study period.

CONCLUSION

as early childhood use of broad spectrum antibiotics is associated with an increased risk of developing asthma in 5-year-olds, it may be hypothesized that the antibiotic- related suppression of allergic inflammatory responses in the course of treatment may later lead to greater than before atopic immune response in Th2 children or an impairment of Th1 immune responses in early childhood.

Antibiotic exposure by 6 months and asthma and allergy at 6 years: Findings in a cohort of 1,401 US children

Many studies have reported that antibiotic use may be associated with increased risk of childhood asthma. Respiratory tract infections in small children may be difficult to distinguish from early symptoms of asthma, and studies may have been confounded by "protopathic" bias, where antibiotics are used to treat early symptoms of asthma. These analyses of a cohort including 1,401 US children assess the association between antibiotic use within the first 6 months of life and asthma and allergy at 6 years of age between 2003 and 2007. Antibiotic exposure was associated with increased risk of asthma (adjusted odds ratio = 1.52, 95% confidence interval (CI): 1.07, 2.16). The odds ratio if asthma was first diagnosed after 3 years of age was 1.66 (95% CI: 0.99, 2.79) and, in children with no history of lower respiratory infection in the first year of life, the odds ratio was 1.66 (95% CI: 1.12, 3.46). The adverse effect of antibiotics was particularly strong in children with no family history of asthma (odds ratio = 1.89, 95% CI: 1.00, 3.58) (P(interaction) = 0.03). The odds ratio for a positive allergy blood or skin test was 1.59 (95% CI: 1.10, 2.28). The results show that early antibiotic use was associated with asthma and allergy at 6 years of age, and that protopathic bias was unlikely to account for the main findings.

Prevalence and impact of ocular allergy in the population attending UK optometric practice

PURPOSE

To determine the prevalence of ocular allergy in patients attending optometric practices in the UK West Midlands and the impact this has on patients' daily lives.

METHOD

Patients attending 9 optometric practices in the West Midlands, UK, were surveyed about the occurrence of ocular allergy, the severity of the symptoms and their treatment. Patients self-reporting ocular allergy were invited to complete a more detailed questionnaire.

RESULTS

Of the 1904 consecutive patients assessed (mean age 47.7±23.2 years, 55% female), 13% reported an allergy, 8% an ocular allergy, rated as at least mild in 85% of cases. Medication was used by 77% of patients reporting ocular symptomology. Patients with ocular allergy (n=126) completed the detailed questionnaire. Seasonal symptoms occurred for 3.4±1.9 months of the year with a peak in June to July. The most common 'hayfever' type symptoms were itchy eyes and a runny nose, and ocular symptoms were itchiness and a desire to rub the eyes. Most had gained medication over the counter (73%) with advice from GPs (53%), pharmacists (41%) or a friend or relative (18%). Only 11% consulted an optometrist. Medication was mainly in the form of antihistamine tablets (71%), eye drops (40%) and nasal spray (40%). Those interested in a specialist ocular allergy service (83%) were willing to pay £15.50 on average.

CONCLUSION

Ocular allergy is relatively common, but treatment is often self-managed, does not appear to totally overcome the discomfort and rarely involves a detailed eye examination.

Paracetamol in early infancy: the risk of childhood allergy and asthma

AIM

We investigated whether paracetamol exposure in pregnancy and until 6 months of age was associated with allergic disease in school children.

METHODS

In a prospective birth cohort study in Oslo, 1016 children included at birth were re-investigated at 10 years. Paracetamol exposure in pregnancy and until 6 months of age was registered. Outcomes at 10 years included current asthma, a history of asthma, allergic sensitization and allergic rhinitis.

RESULTS

Maternal paracetamol use in the first trimester increased the risk for allergic rhinitis at 10 years OR (odds ratio) (95%CI) 2.30 (1.06, 4.97) in boys and girls. Paracetamol use until 6 months in girls increased the risk for allergic sensitization OR 2.20 (1.15, 4.22) and a history of asthma OR 2.20 (1.13, 4.30). The ORs for allergic sensitization and history of asthma in girls remained unchanged adjusting for upper or lower airway infections during the first 6 months of life.

CONCLUSION

Paracetamol exposure in pregnancy was associated with allergic rhinitis, but not with asthma or allergic sensitization at 10 years of age. Paracetamol used until 6 months of age was associated with allergic sensitization and having a history of asthma in girls at 10 years of age, even considering concomitant airway infections.

Infections and asthma: new insights into old ideas

A relationship between infections and allergic airway disease has long been recognized, and many reviews have been written on this topic. However, both clinical and basic science studies published in the last 3 years provide new insights into the relationship between infection and allergic conditions. In this review, we focus on these very recent studies, which address the role of infection in the development, maintenance, and exacerbation of asthma. Bacterial, viral, fungal, and parasitic infections have each been examined and provide a framework for these novel concepts.

Early exposure to paracetamol or to antibiotics and eczema at school age: modification by asthma and rhinoconjunctivitis

The association between early exposure to paracetamol or to antibiotics and eczema is conflicting. This study aims to know whether the early exposure to those drugs is associated with eczema at school age, and whether the strength of the association is modified by the presence of asthma or rhinoconjunctivitis. Children aged 6-7 (n = 13908) from the International Study of Asthma and Allergies in Childhood in Spain provided data about current asthma, rhinoconjunctivitis and eczema. Parent-reported information was also obtained on paracetamol and antibiotic consumption during the first year of life. Logistic regression analysis with eczema as outcome and including exposure to paracetamol or to antibiotics, together with possible confounders, was carried out in the whole sample of children and in five different strata: no respiratory symptom and any respiratory symptom further subdivided into: asthma with rhinoconjunctivitis, asthma without rhinoconjunctivitis and rhinoconjunctivitis without asthma. In the whole sample, exposure to paracetamol was associated with eczema (aOR 1.56 [1.36-1.80]) as was antibiotic consumption (aOR 1.66 [1.43-1.92]). These associations did not substantially change after additionally adjusting for the other drug. A similar pattern was found among children without respiratory symptoms. In children with symptoms, adjusting for the other drug modified the association with paracetamol (aOR from 1.32 [1.03-1.71] to 1.09 [0.83-1.43]) but did not change that with antibiotics (aOR from 1.80 [1.38-2.35] to 1.81 [1.37-2.39]). Early exposure to paracetamol or to antibiotics is associated with an increased prevalence of eczema at school age. Asthma and/or rhinoconjunctivitis substantially modifies this association.

Paracetamol use in early life and asthma: prospective birth cohort study

OBJECTIVE

To determine if use of paracetamol in early life is an independent risk factor for childhood asthma.

DESIGN

Prospective birth cohort study.

SETTING

Melbourne Atopy Cohort Study.

PARTICIPANTS

620 children with a family history of allergic disease, with paracetamol use prospectively documented on 18 occasions from birth to 2 years of age, followed until age 7 years.

MAIN OUTCOME MEASURES

The primary outcome was childhood asthma, ascertained by questionnaire at 6 and 7 years. Secondary outcomes were infantile wheeze, allergic rhinitis, eczema, and skin prick test positivity.

RESULTS

Paracetamol had been used in 51% (295/575) of children by 12 weeks of age and in 97% (556/575) by 2 years. Between 6 and 7 years, 80% (495/620) were followed up; 30% (148) had current asthma. Increasing frequency of paracetamol use was weakly associated with increased risk of childhood asthma (crude odds ratio 1.18, 95% confidence interval 1.00 to 1.39, per doubling of days of use). However, after adjustment for frequency of respiratory infections, this association essentially disappeared (odds ratio 1.08, 0.91 to 1.29). Paracetamol use for non-respiratory causes was not associated with asthma (crude odds ratio 0.95, 0.81 to 1.12).

CONCLUSIONS

In children with a family history of allergic diseases, no association was found between early paracetamol use and risk of subsequent allergic disease after adjustment for respiratory infections or when paracetamol use was restricted to non-respiratory tract infections. These findings suggest that early paracetamol use does not increase the risk of asthma.

Acetaminophen use and risk of asthma, rhinoconjunctivitis, and eczema in adolescents: International Study of Asthma and Allergies in Childhood Phase Three

RATIONALE

There is epidemiological evidence that the use of acetaminophen may increase the risk of developing asthma.

OBJECTIVES

To investigate the risk of asthma and other allergic disorders associated with the current use of acetaminophen in 13- to 14-year-old children in different populations worldwide.

METHODS

As part of the International Study of Asthma and Allergies in Childhood (ISAAC) Phase Three, 13- to 14-year-old children completed written and video questionnaires obtaining data on current symptoms of asthma, rhinoconjunctivitis, and eczema, and a written environmental questionnaire obtaining data on putative risk factors, including acetaminophen use in the past 12 months.

MEASUREMENTS AND MAIN RESULTS

The primary outcome measure was the odds ratio (OR) of current asthma symptoms associated with acetaminophen use calculated by logistic regression. A total of 322,959 adolescent children from 113 centers in 50 countries participated. In the multivariate analyses the recent use of acetaminophen was associated with an exposure-dependent increased risk of current asthma symptoms (OR, 1.43 [95% confidence interval, 1.33-1.53] and 2.51 [95% confidence interval, 2.33-2.70] for medium and high versus no use, respectively). Acetaminophen use was also associated with an exposure-dependent increased risk of current symptoms of rhinoconjunctivitis and eczema.

CONCLUSIONS

Acetaminophen use may represent an important risk factor for the development and/or maintenance of asthma, rhinoconjunctivitis, and eczema in adolescent children.

Relation of early antibiotic use to childhood asthma: confounding by indication?

BACKGROUND

Findings from studies of the relation between early antibiotic use and subsequent asthma have been inconsistent, which may be attributable to methodologic issues.

OBJECTIVE

Our objective was to assess the impact of confounding by indication on the relation of early antibiotic use to childhood asthma through age 5 in a non-selected birth cohort (n=424).

METHODS

Oral antibiotic use was assessed by frequent nurse interviews in the first 9 months of life. Physician-diagnosed active asthma and eczema were assessed by questionnaire at 1, 2, 3, and 5 years, and were considered as ever asthma or ever eczema if positive at any age. Allergen-specific IgE was assessed in plasma at 1, 2, 3, and 5 years. Confounding by indication was investigated by considering the relation of asthma to antibiotic use while controlling for the number of illness visits to a physician in early life.

RESULTS

There was no statistically significant relation of early antibiotic use with physician-diagnosed eczema or allergen-specific IgE. A dose-response relation was evident for antibiotic use with ever asthma (odds ratio [OR]=1.5, P=0.047). Ever asthma also increased significantly with the number of illness visits to a physician (P<0.001). After adjustment for number of illness visits, antibiotic use showed no relation with asthma.

CONCLUSIONS

The relation of asthma to antibiotics in this cohort appears to be an artefact of the strong relation of number of physician visits for illness with both antibiotic use and risk for asthma.

The role of paracetamol in the pathogenesis of asthma

Paracetamol use represents a putative risk factor for the development of asthma. There is convincing epidemiological evidence that the risk of asthma may be increased with exposure to paracetamol in the intrauterine environment, infancy, later childhood and adult life. A dose-dependent association has also been observed in these different age groups in different populations world-wide. An association has also been shown between paracetamol use in both rhinoconjunctivitis and eczema. There is biological plausibility with paracetamol use leading to decreased glutathione levels resulting in increased oxidant-induced inflammation and potentially enhanced T-helper type 2 responses. At the population level, patterns of paracetamol use might explain, to some extent, the world-wide variation in the prevalence of asthma and related disorders, particularly the high rates in English-speaking countries, which have high per capita prescription and over-the-counter use of paracetamol. A temporal association also exists between the international trends of increasing paracetamol use and increasing prevalence of asthma over recent decades. Further research is urgently required, in particular randomized-controlled trials (RCTs) into the long-term effects of frequent paracetamol use in childhood, to determine the magnitude and characteristics of any such risk. Importantly, RCTs will also enable evidence-based guidelines for the recommended use of paracetamol to be developed.