Jos Droste

Does the use of antibiotics in early childhood increase the risk of asthma and allergic disease

One of the mechanisms evoked to explain the increasing prevalences of asthma and allergy, in particular among children, is the ‘Western lifestyle’ or ‘hygiene’ hypothesis. As early childhood infections are assumed to hold a protective effect on the development of asthma and allergies, the use of antibiotics at that sensitive age may lead to an increased risk of asthma and allergy.

Pre‐ and post‐natal exposure to antibiotics and the development of eczema, recurrent wheezing and atopic sensitization in children up to the age of 4 years

Background Little data are available on the relationship between indirect antibiotic exposure of the child in utero or during lactation and allergic diseases. On the other hand, several studies have been conducted on the association with direct post‐natal antibiotic exposure, but the results are conflicting.

Early exposure to solid foods and the development of eczema in children up to 4 years of age.

Sariachvili M, Droste J, Dom S, Wieringa M, Hagendorens M, Stevens W, van Sprundel M, Desager K, Weyler J. Early exposure to solid foods and the development of eczema in children up to 4 years of age.
Pediatr Allergy Immunol 2010: 21: 74–81.
© 2009 John Wiley & Sons A/S

Occupational risk factors of lung cancer: a hospital based case-control study.

OBJECTIVES: To investigate the relation between lung cancer and exposure to occupational carcinogens in a highly industrialised region in western Europe. METHODS: In a case-control study 478 cases and 536 controls, recruited from 10 hospitals in the Antwerp region, were interviewed. Cases were male patients with histologically confirmed lung cancer; controls were male patients without cancer or primary lung diseases. Data were collected by questionnaires to obtain information on occupations, exposures, and smoking history. Job titles were coded with the Office of Populations, Censuses and Surveys industrial classification. Exposure was assessed by self report and by job-task exposure matrix. Exposure odds ratios were calculated with logistic regression analysis adjusted for age, smoking history, and marital and socio-economic status. RESULTS: A job history in the categories manufacturing of transport equipment other than automobiles (for example, shipyard workers), transport support services (for example, dockers), and manufacturing of metal goods (for example, welders) was significantly associated with lung cancer (odds ratios (ORs) 2.3, 1.6, and 1.6 respectively). These associations were independent of smoking, education, civil, and economic status. Self reported exposure to potential carcinogens did not show significant associations with lung cancer, probably due to nondifferential misclassification. When assessed by job-task exposure matrix, exposure to molybdenum, mineral oils, and chromium were significantly associated with lung cancer. A strong association existed between smoking and lung cancer: OR of ex-smokers 4.2, OR of current smokers 14.5 v non-smokers. However, smoking did not confound the relation between occupational exposure and lung cancer. CONCLUSIONS: The study has shown a significant excess risk of lung cancer among workers in manufacturing of metal goods, manufacturing of transport equipment (other than automobiles), and transport support services. Assessment of exposure to specific carcinogens resulted in significant associations of chromium, mineral oils, and molybdenum with lung cancer. This study is, to our knowledge, the first study reporting a significant association between occupational exposure to molybdenum and lung cancer.

Is breast feeding a risk factor for eczema during the first year of life

Breast feeding (BF) provides many advantages to the offspring; however, at present there is an ongoing debate as to whether or not it prevents allergic diseases. The aim of the current study was to investigate the effect of duration of BF on eczema in the first year of life. A birth cohort of 1128 infants was followed prospectively from 5 months of pregnancy. Data were collected using questionnaires, a medical examination and blood tests for allergy at the age of 1 yr. Breast feeding was not statistically significant associated with eczema in the first year of life [adj ORs with 95% CIs: 0.8 (0.4–1.3), 0.8 (0.5–1.3) and 1.0 (0.6–1.5) for BF duration of 1–6 wk, 7–12 wk and ≥13 wk, respectively]. Eczema was positively associated with atopy and educational level of the mother, use of antibiotics in pregnancy and passive smoking by the child during the first 12 months. Regular postnatal contact of the infants with dogs was inversely associated with eczema. Breast feeding was positively associated with eczema among children with non‐atopic parents [adj ORs with 95% CIs: 2.1 (0.4–10.6), 2.2 (0.4–11.3) and 1.9 (0.4–8.5) for BF duration of 1–6 wk, 7–12 wk and ≥13 wk, respectively], whereas an inverse association was found among children with atopic parents [adj ORs with 95% CIs: 0.6 (0.3–1.3), 0.7 (0.3–1.4) and 0.9 (0.5–1.7) for the same BF durations]. However, these associations were not statistically significant. Breast feeding has no significant effect on the prevalence of eczema in the first year of life. The effect of BF on eczema in children depends on parental atopy.

Lung function measures and their relationship to respiratory symptoms in 7- and 8-year-old children

Abnormal pulmonary function in childhood is a well‐known risk factor for lung function impairment in adult life. It is therefore of clinical interest to recognize lower pulmonary function in childhood. We investigated the association between asthma‐like respiratory symptoms and the lung function parameters FVC, FEV1, and FEF25–75 in a population‐based sample of 402 schoolchildren, aged 7 and 8 years, using linear regression analyses.

The influence of parental educational level on the development of atopic sensitization, wheezing and eczema during the first year of life

Several studies have investigated the association between socioeconomic status and the occurrence of allergies. Nevertheless, the results remain contradictory. The aim of this study was to evaluate the associations between parental education and the occurrence of atopic sensitization, recurrent wheezing and eczema during the first year of life, differentiating between atopic and non‐atopic disorders based on specific serum IgE. We conducted an aetiological study in 690 children, based on a prospective birth cohort project in which environmental and health information was gathered using questionnaires. At the age of 1 yr a blood sample was taken for quantification of specific IgE. Adjusted odds ratios and 95% confidence intervals were computed as measures of association between the outcomes and parental education. Parental educational level was positively associated with the occurrence of atopic sensitization (OR: 2.1; 95% CI: 1.0–4.4) and eczema (OR: 1.9; 95% CI: 1.1–3.4), but negatively with the occurrence of recurrent wheezing (OR: 0.4; 95% CI: 0.2–0.8) in the first year of life. Atopic recurrent wheezing was positively associated with the education of the parents, whereas non‐atopic recurrent wheezing was negatively associated. When maternal and paternal education were considered separately, only maternal education had a significant influence. Our results suggest that aspects associated with a high maternal educational level may play an important role in the development of atopic disorders.

CHANGES IN RESPIRATORY AND ALLERGIC SYMPTOMS IN SCHOOLCHILDREN FROM 1996 TO 2002, RESULTS FROM THE ISAAC SURVEYS IN ANTWERP (BELGIUM)

Abstract Two cross sectional surveys (1995/1996 and 2001/2002) were carried out according to the ISAAC protocol among 6-7 and 13-14 year old schoolchildren in Antwerp, Belgium. A total of 8244 children participated in 1996 and 8159 children in 2002. No significant differences in current prevalence of asthma and asthma medication was found in 6-7 year olds and 13-14 year old girls. Significantly less asthma and asthma medication was reported by 13-14 year old boys in 2002. Symptoms of wheeze had lower occurrence in all groups in 2002, which was significant for older age group. Current prevalence of rash was significantly higher in the 6-7 year olds in 2002. No such increase was found for rash in the older age groups but they reported significantly more rhinitis. No differences were found between urban and suburban Antwerp in either survey. No clear changes in the occurrence of asthma were found for school children in Antwerp while wheeze was reported less in 2002 compared to 1996. Allergic disorders had higher occurrences in schoolchildren in 2002.

Work-related health symptoms among compost facility workers: a cross-sectional study

BackgroundIndustrial composting is a relatively new and expanding activity. Several studies indicate that compost workers are at risk to develop health symptoms. The aim of this study was to assess the prevalence of work-related health symptoms among compost workers compared with control subjects.MethodsA questionnaire was distributed among 62 workers (31 exposed and 31 non-exposed workers). Data were analyzed using simple and multiple logistic regression analyses.ResultsWorkers exposed to organic dust reported significantly more often respiratory, irritation (e.g., eyes, nose and throat), gastrointestinal, and skin symptoms than the non-exposed group. Moreover, all work-related symptoms were significantly more often reported by exposed than non-exposed workers. After adjustment for smoking status and age, the associations between exposure and respiratory, gastrointestinal, and skin symptoms remained statistically significant, in particular if these symptoms were work-related.ConclusionsThis study confirms that workers at compost facilities are at risk to develop occupational health problems, most likely related to organic dust exposure.

Occupational exposure among bakery workers: impact on the occurrence of work-related symptoms as compared with allergic characteristics

Objective: The aim of the study is to examine the relationship between exposure to occupational allergens, sensitization, and atopy and several outcome variables and the independent associations of these interrelated risk factors to work-related symptoms in particular. Methods: Data were collected by questionnaire, skin prick tests, lung function tests, and exposure measurements among 246 workers from 74 bakeries and analyzed using logistic and linear regression analyses. Results: Exposure levels were associated with respiratory symptoms, sensitization to baker’s allergens, and lung function. High exposure and sensitization to common and bakers’ allergens were independent risk factors for work-related symptoms. However, allergy determinants performed best in predicting work-related symptoms. Conclusions: Current exposure to occupational allergens is a risk factor for work-related symptoms, but sensitization to occupational allergens and atopy are more adequate and easier obtainable predictors of work-related symptoms.