Assessing the prevalence and severity of asthma, rhinitis, and eczema among schoolchildren (6-7 and 13-14 years old) in Khuzestan, Iran: a cross-sectional survey

Prevalence of asthma among children and adolescents in WHO's Eastern Mediterranean Region: a meta-analysis of over 0.5 million participants

OBJECTIVE

This study aims to evaluate the epidemiology of asthma among children and adolescents in the Eastern Mediterranean Region.

METHODS

Exhaustive searches were conducted across databases, including PubMed, Scopus, Web of Knowledge Core Collection, Embase, and Google Scholar. The selection criteria included studies reporting asthma prevalence in individuals aged 0 to 19 years, using validated questionnaires. Data were extracted and synthesized using the DerSimonian and Laird random effects model.

RESULTS

The overall prevalence of asthma in Eastern Mediterranean Regional Office (EMRO) countries, among the 514,468 children and adolescents included in this meta-analysis, was 10.61%, synthesized from 95 studies. Among the countries studied, Qatar exhibited the highest prevalence at 16.69%, followed by Saudi Arabia at 16.57%, Iraq at 16.22%, Oman at 15.20%, and Afghanistan at 14.90%. Adolescents showed a slightly higher prevalence of asthma at 10.10% compared to children at 9.70%. Boys exhibited a higher prevalence at 11.48% compared to girls at 9.75%. Urban areas demonstrated a higher prevalence at 11.27% than rural areas at 8.29%.

CONCLUSION

Efforts to reduce asthma prevalence in Arab countries and address underdiagnosis in African nations within the EMRO are crucial. Targeted interventions should focus on addressing environmental triggers and improving access to healthcare. Enhanced diagnostic capabilities and healthcare infrastructure are necessary in African countries. Collaborative action is essential to alleviate the asthma burden and promote respiratory health across the EMRO region.

Respiratory Status in Children and Exposure to Animal Allergens-The Problem of Reverse Causality in Cross-Sectional Studies

BACKGROUND

Some epidemiological studies suggest that early exposure to animal allergens during infancy reduces the risk of bronchial asthma in school-age children. However, the observed associations in some cases may be an effect of the study used (epidemiological observational studies, especially a cross-sectional study) and indicate reverse causality.

AIM

This study aimed to determine the association between exposure to animal allergens and the prevalence of respiratory diseases, including bronchial asthma, considering the potential impact of reverse causality on the observed relationships.

MATERIAL AND METHODS

An analysis of data from a cross-sectional epidemiological study conducted in 2020 involving 3237 primary school students aged 7-15 years in the Silesian Province (Southern Poland) was carried out. The parents of students completed a questionnaire based on The International Study on Asthma and Allergies in Childhood (ISAAC). The relationship between the occurrence of chronic cough, wheezing, and dyspnea in the last 12 months, night waking due to dyspnea, and asthma in the presence of pets was assessed. Exposure to animal allergens was determined by answering the question, "Are there any furry or feathered animals in the home?" with three response options: "yes; they have been in the past; no" (Scenario 1). For the analyses and to reveal a potential reverse causality effect, the last two response categories regarding pet ownership were combined to form a "no" category in Scenario 2, and the first two answers were combined into a "yes" category in Scenario 3. A chi-square test was used to assess the relationship between variables, and a statistical significance level of p < 0.05 was adopted.

RESULTS

Chronic cough affected 9.5% of children, wheezing in the last 12 months-9.2%, night waking due to dyspnea-5.8%, dyspnea in the last 12 months-4.8%, bronchial asthma-9.2%. Analysis considering the category of having or not having pets (yes vs. no) showed that bronchial asthma was statistically significantly more common in children who did not have pets at home (10.9% vs. 7.9%, p = 0.002). A similar situation was observed for wheezing in the past 12 months (10.7% vs. 8.1%; p = 0.01) and nocturnal awakening due to dyspnea (6.8% vs. 5.1%, p = 0.03). No statistically significant differences were observed for the other symptoms. Analysis by time of pet ownership (a. present; b. present but in the past; c. not present) highlighted similar relationships. Asthma (a. 7.7% vs. b. 13.4% vs. c. 7.7%; p = 0.004), wheezing in the past 12 months (a. 8.1% vs. b. 8.9% vs. c. 10.9%, p = 0.03) and night waking (a. 5.0% vs. b. 4.5% vs. c. 7.1%; p = 0.04) were more common in children without pets and those who had owned pets in the past. The highest proportion of children with asthma was in homes where pets were present in the past.

CONCLUSIONS

Analyses indicating a relationship between a higher prevalence of asthma and some respiratory symptoms, and the absence of pets cannot be considered as a casual association. The analysis conducted did not reveal a reverse causality effect. The results of observational epidemiological studies, especially a cross-sectional study, should always be interpreted with caution, considering possible distortions and conclusions drawn.

Facteurs aggravants la rhinite allergique de l’enfant

INTRODUCTION

Allergic rhinitis (AR) in children is a common condition that is a public health problem. Despite a well-codified treatment, clinical improvement is not the rule.

AIM

To identify factors affecting the improvement of allergic rhinitis in children under symptomatic treatment.

METHODS

A 12-year retrospective descriptive study that included children aged 3 to 15 years, followed for allergic rhinitis. The search for explanatory factors for improvement under treatment was done using a binary logistic regression model.

RESULTS

52 children were included, with a mean age of 7 years (±3). A familial atopy history was present in 37 patients (71%). The presence of factors aggravating allergy was noted, including antibiotic consumption: 31 patients (60%) and overweight: 15 patients (29%). Associated asthma was noted in 42 patients (81%). The allergenic profile has regained a predominance of dust mite allergy (71%) and a significant frequency of multiallergies (79%). Management included therapeutic education and drug treatment. There was improvement in rhinitis in 27 patients (52%) and improvement in asthma in 26 patients (50%). Overweight and high consumption of antibiotics had a negative impact on the therapeutic outcome. A good therapeutic education had a favorable impact.

CONCLUSION

AR is a debilitating condition requiring prolonged therapeutic education and drug treatment. The prescription of antibiotics in children with allergic rhinitis should be sparing and weight monitored.

Seroprevalence and Potential Risk Factors of Toxocariasis among General Population in Southwest Iran: Implications on the One Health Approach

Toxocariasis is one of the most common zoonotic diseases distributed worldwide. This study aimed to estimate the seroprevalence of anti-Toxocara immunoglobulin G (IgG) antibodies and the associated risk factors among general populations living in urban and rural areas of Abadan and Khorramshahr cities in Khuzestan Province, Southwest Iran. This cross-sectional study was conducted between March and September 2022. There were 363 participants (190 females and 173 males) aged from <20 to ≥60 years old. Anti-Toxocara IgG antibodies in serum samples were measured using a commercially available enzyme-linked immunosorbent assay (ELISA). A structured questionnaire was employed to collect information regarding sociodemographic status and probable risk factors associated with toxocariasis. It was found that the seroprevalence rate in males (15.0%, 95% CI = 10.47-21.11) was higher than in females (10.5%, 95% CI = 6.92-15.70). Moreover, we observed that the seroprevalence was higher in participants at younger ages compared to other age ranges (COR = 2.55, 95% CI = 0.92-7.12, p =0.073). The findings of the univariate analysis revealed that residency in rural areas (p  < 0.001), using unpurified water (p  < 0.001), contact with dog (p =0.002), contact with soil (p  < 0.001), consumption of improperly washed vegetables (p  < 0.001), and history of drinking untreated water (p  < 0.001) were risk factors associated with toxocariasis. Further comprehensive studies with a focus on humans and animals should be designed in different areas of the Province. The data represented by the current study are useful to health policymakers to consider precise surveillance and effective prevention measures to control this zoonotic infection among general populations.

Exposure to household secondhand tobacco smoke and the odds of developing atopic dermatitis among adolescents: A causal mediation analysis

INTRODUCTION

Exposure to household secondhand tobacco smoke (SHS) among adolescents has been shown to be associated with atopic dermatitis, and affects disproportionality females. However, the mechanisms underlying this link are uncertain. This study sought to identify modifiable factors that mediate the relationship between household SHS exposure and atopic dermatitis among adolescents.

METHODS

During October 2015, a cross-sectional study was conducted using the ISAAC questionnaire for data collection from adolescents enrolled in nine high schools of Hawalli - one of the six governorates of Kuwait. Data were collected on sociodemographic characteristics, self-reported tobacco smoking among adolescents, household SHS exposure (≥1 smokers at home vs none), self-reported asthma and atopic dermatitis. For causal mediation analysis an inverse odds-weighting approach was used.

RESULTS

Of 746 participants, 74.8% were Kuwaiti, 50.1% were female, 12.4% were regular daily smokers and 54.1% had household SHS exposure, which was more common among Kuwaiti (79.6%) than non-Kuwaiti (20.4%) adolescents. The prevalences of self-reported asthma and atopic dermatitis were 20.6% and 14.9%, respectively. After adjusting for the pre-exposure covariates (i.e. sex and nativity), household SHS exposure had a significant (p=0.043) total effect, non-significant (p=0.133) natural direct effect, and marginally insignificant (p=0.058) natural indirect effect, which were jointly mediated by asthma status and adolescent's self-reported smoking status, with a proportion of mediated risk to atopic dermatitis of 29.6%.

CONCLUSIONS

Asthma and self-tobacco smoking among adolescents not only directly affected but also mediated household SHS exposure effect on atopic dermatitis risk. Voluntarily adopting a smoke-free home rule may minimize household SHS exposure, reduce the odds of developing asthma, and deter the initiation of tobacco smoking among adolescents. Such an effort will likely mitigate the atopic dermatitis risk among adolescents in this and other similar settings. If implemented, future studies may contemplate evaluating the impact of such intervention.

Nuts, vegetables, fruits, and protein dietary pattern during pregnancy is inversely associated with risk of childhood allergies: a case-control study

Allergic diseases are prevalent chronic conditions among children and can lead to significant health and economic issues. It is hypothesized that healthy and high quality diet during pregnancy can prevent the onset of allergic diseases in offspring. This study aimed to investigate the potential relationship between major dietary patterns during pregnancy and allergies in children under one year of age. This case-control study was conducted involving 244 participants (122 mothers of allergic children and 122 healthy controls) who visited pediatricians and allergy outpatient clinics in Khuzestan Province, Iran, between June 2022 and March 2023. Demographic information was recorded using a socio-demographic questionnaire. A food frequency questionnaire was used to identify the foods consumed during pregnancy. Major dietary patterns were extracted using principal component analysis, and the potential relationship between these patterns and childhood allergies was investigated using multivariable logistic regression models. The crude odds ratio (OR) analysis showed that the fourth quartile of "Nut, vegetables, fruits, and protein" dietary pattern was associated with lower occurrence of childhood allergies (OR: 0.214, 95% CI = 0.068-0.679; P trend = 0.211). After adjusting for cofactors in Model 3, this association was still observed in the fourth quartile (OR = 0.108, 95% CI = 0.019-0.613; P trend, 0.001). However, no significant association was observed between "Carbohydrate and cereals" and "Salty" dietary patterns and childhood allergies. The study findings suggest that a maternal dietary pattern rich in nuts, vegetables, and fruits during pregnancy may reduce the risk of allergic diseases in offspring.