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B Brunekreef

Publications and source records attributed to B Brunekreef.

At least 55 records · Page 3Linked to original sources
PubMed2003

Nutrition and respiratory health in children in six Central and Eastern European countries.

BACKGROUND: The results of studies on the effect of nutrition on respiratory diseases are inconsistent. The role of nutrition in children's respiratory health was therefore analysed within the cross sectional Central European Study on Air Pollution and Respiratory Health (CESAR). METHOD: A total of 20 271 children aged 7-11 were surveyed in six European countries. Respiratory health and food intake were assessed using questionnaires. Associations between four symptoms and nutritional factors were evaluated using logistic regression, controlling for area plus other potential confounders. RESULTS: All symptoms showed initial associations with nutritional factors. Low consumption of fish and of summer and winter fruit were the most consistent predictors. In a fully adjusted model low fish intake remained a significant independent predictor of persistent cough (OR=1.18; 95% CI 1.04 to 1.34), wheeze ever (OR=1.14; 95% CI 1.03 to 1.25) and current wheeze (OR=1.21; 95% CI 1.06 to 1.39) and a weaker predictor of winter cough (OR=1.10; 95% CI 0.99 to 1.23). Low summer fruit intake was a predictor of winter cough (OR=1.40; 95% CI 1.10 to 1.79) and persistent cough (OR=1.35; 95% CI 1.01 to 1.82). Low winter fruit intake was associated with winter cough (OR=1.28; 95% CI 1.09 to 1.51). Associations between symptoms and vegetable intake were inconsistent. Low summer intake was significantly associated with winter cough (OR=1.23; 95% CI 1.03 to 1.47) but, overall, winter intake had inverse associations with both coughs. Associations between winter vegetable intake and wheeze varied considerably between countries. CONCLUSION: A number of associations were found between respiratory symptoms and low intake of fish, fruit and vegetables in children. Low fish intake was the most consistent predictor of poor respiratory health. Fruit and vegetable intake showed stronger associations with cough than with wheeze.

Child↗
PubMed2003

Relationship between exhaled NO, respiratory symptoms, lung function, bronchial hyperresponsiveness, and blood eosinophilia in school children.

BACKGROUND: Exhaled nitric oxide (eNO) may serve as a non-invasive marker of airway inflammation but its relationship with other commonly used measures has not been evaluated. METHODS: Levels of eNO in a sample of 450 children aged 7-12 years out of a total sample of 2504 school children living in different urban areas near motorways were determined. The aim of this cross-sectional study was to explore the relationship between eNO, impairment of lung function (PEF, FVC, FEV(1) and MMEF), bronchial hyperresponsiveness (BHR), and blood eosinophilia in children with and without atopy as assessed by skin prick testing. RESULTS: Regression analysis showed that wheezing and nasal discharge and conjunctivitis that had occurred during the previous 12 months were positively associated with eNO levels in atopic children (relative increase of 1.48 and 1.41, respectively; p<0.05) but not in non-atopic children. Similarly, BHR and the number of blood eosinophils per ml were positively associated with eNO levels in atopic children (relative increase of 1.55 and 2.29, respectively; p<0.05) but not in non-atopic children. The lung function indices PEF, FVC, FEV(1) and MMEF were not associated with eNO levels. CONCLUSIONS: In addition to conventional lung function tests and symptom questionnaires, eNO is a suitable measure of airway inflammation and its application may reinforce the power of epidemiological surveys on respiratory health.

Bronchitis↗
PubMed2003

Association of consumption of products containing milk fat with reduced asthma risk in pre-school children: the PIAMA birth cohort study.

BACKGROUND: Environment and lifestyle contribute to the development of asthma in children. Understanding the relevant factors in this relationship may provide methods of prevention. The role of diet in the development of asthma in pre-school children was investigated. METHODS: Data from 2978 children participating in a prospective birth cohort study were used. Food frequency data were collected at the age of 2 years and related to asthma symptoms reported at the age of 3 years. RESULTS: The prevalence of recent asthma at age 3 was lower in children who consumed (at age 2) full cream milk daily (3.4%) than in those who did not (5.6%) and in those who consumed butter daily (1.5%) than in those who did not (5.1%). The prevalence of recent wheeze was lower in children who consumed milk products daily (13.7%) than in those who did not (18.4%) and in children who consumed butter daily (7.7%) than in those who did not (15.4%). These effects remained in a logistic regression model including different foods and confounders (adjusted odds ratio (CI) for recent asthma: full cream milk daily v rarely 0.59 (0.40 to 0.88), butter daily v rarely 0.28 (0.09 to 0.88)). Daily consumption of brown bread was also associated with lower rates of asthma and wheeze, whereas no associations were observed with the consumption of fruits, vegetables, margarine, and fish. CONCLUSIONS: In pre-school children, frequent consumption of products containing milk fat is associated with a reduced risk of asthma symptoms.

Animals↗
PubMed2003

Short and long term variability of the interrupter technique under field and standardised conditions in 3-6 year old children.

BACKGROUND: The short and long term variability of the interrupter technique was assessed to determine whether interrupter resistance is a stable individual characteristic over time. The effect of field and standardised measurement conditions on the within-subject variability of the interrupter technique was also examined. METHODS: The interrupter technique was studied under field and standardised conditions in children aged 3-6 years. Under field conditions, five investigators performed the measurements using two different measurement devices in random sequence. Both short term (20-30 minutes) and long term variability (median 38 days) were assessed in 32 children. Under standardised conditions, a single investigator conducted all measurements using a single device; the repeated measurements were conducted at the same time of day in a familiar quiet classroom. Long term variability (median 11 days) was estimated in 15 children. Within-subject standard deviations were estimated by analysis of variance with adjustment for the effects of different investigators and measurement devices on within-subject variability under field conditions. RESULTS: Under field conditions within-subject standard deviations for short and long term variability were 0.10 kPa/l/s (adjusted 0.10 kPa/l/s) and 0.13 kPa/l/s (adjusted 0.14 kPa/l/s), respectively. Under standardised conditions the within-subject standard deviation for long term variability was 0.10 kPa/l/s. CONCLUSIONS: Measurement of interrupter resistance under field conditions only slightly increased the within-subject variability compared with standardised conditions. The results indicate that interrupter resistance is a stable individual characteristic over a period of some weeks.

Airway Resistance↗
PubMed2003

Air pollution and mortality in The Netherlands: are the elderly more at risk?

The association between daily mortality and short-term variations in the ambient levels of ozone (O3), black smoke (BS), sulphur dioxide (SO2), nitrogen dioxide (NO2), carbon monoxide (CO) and particulate matter was studied in The Netherlands. Daily total and cause-specific mortality counts (cardiovascular, chronic obstructive pulmonary disease (COPD) and pneumonia), air quality, temperature, relative humidity and influenza data were obtained from 1986-1994. The relationship between daily mortality and air pollution was modelled using Poisson regression analysis. All pollution mortality associations were adjusted for potential confounding due to long-term trends, seasonal trends, influenza epidemics, ambient temperature, ambient relative humidity, day of the week and holidays, using generalised additive models. Statistically significant associations were mostly found in the elderly, that is the age categories of 65-74 and > or = 75 yrs for the pollutants PM10 (particles with a 50%, cut-off aerodynamic diameter of 10 microm), BS, SO2, NO2 and CO. This may partly be due to a better precision of relative risk (RR) estimates for the larger numbers of deaths in these age groups. Significant associations for those < 65 yrs were found for O3 (total and COPD mortality), PM10 (pneumonia), NO2 (pneumonia) and CO (pneumonia). RR estimates for deaths between 45-65 yrs tended to be smaller than those in > 65 yrs, with the exception of ozone; for cardiovascular mortality the RR for PM10, O3 and CO were similar in these age groups. In conclusion, larger relative risks for air pollution were mostly found in the elderly except for ozone and for death-cause pneumonia which showed larger relative risk in younger age groups.

Aged↗
PubMed2002

Early, current and past pet ownership: associations with sensitization, bronchial responsiveness and allergic symptoms in school children.

BACKGROUND: Studies have suggested that early contact with pets may prevent the development of allergy and asthma. OBJECTIVE: To study the association between early, current and past pet ownership and sensitization, bronchial responsiveness and allergic symptoms in school children. METHODS: A population of almost 3000 primary school children was investigated using protocols of the International Study on Asthma and Allergies in Childhood (ISAAC). Allergic symptoms were measured using the parent-completed ISAAC questionnaire. Sensitization to common allergens was measured using skin prick tests (SPT)s and/or serum immunoglobulin (Ig)E determinations. Bronchial responsiveness was tested using a hypertonic saline challenge. Pet ownership was investigated by questionnaire. Current, past and early exposure to pets was documented separately for cats, dogs, rodents and birds. The data on current, past and early pet exposure were then related to allergic symptoms, sensitization and bronchial responsiveness. RESULTS: Among children currently exposed to pets, there was significantly less sensitization to cat (odds ratio (OR) = 0.69) and dog (OR = 0.63) allergens, indoor allergens in general (OR = 0.64), and outdoor allergens (OR = 0.60) compared to children who never had pets in the home. There was also less hayfever (OR = 0.66) and rhinitis (OR = 0.76). In contrast, wheeze, asthma and bronchial responsiveness were not associated with current pet ownership. Odds ratios associated with past pet ownership were generally above unity, and significant for asthma in the adjusted analysis (OR = 1.85), suggesting selective avoidance in families with sensitized and/or symptomatic children. Pet ownership in the first two years of life only showed an inverse association with sensitization to pollen: OR = 0.71 for having had furry or feathery pets in general in the first two years of life, and OR = 0.73 for having had cats and/or dogs in the first two years of life, compared to not having had pets in the first two years of life. CONCLUSION: These results suggest that the inverse association between current pet ownership and sensitization and hayfever symptoms was partly due to the removal of pets in families with sensitized and/or symptomatic children. Pet ownership in the first two years of life only seemed to offer some protection against sensitization to pollen.

Animals↗
PubMed2002

A lower prevalence of atopy symptoms in children with type 1 diabetes mellitus.

BACKGROUND: The Th1/Th 2 concept is a model to understand the pathophysiology of certain diseases. Atopic diseases (asthma, eczema and hayfever) are characterized by a chronic inflammatory reaction that is dominated by Th 2 cells, and type 1 diabetes mellitus (DM) is Th1 cell dominated. Because it is known that Th1 and Th 2 cells reciprocally counteract each other, it can be speculated that the prevalence of Th 2-mediated disease is lower in patients with Th1-mediated disease. OBJECTIVE: To compare the prevalence of atopic diseases between children with DM and age-matched controls. METHODS: Parents of children with DM were requested by Dutch paediatricians to complete the International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire on the prevalence of atopic diseases. A control group was derived from a Dutch cross-sectional survey (the ISAAC2 study). RESULTS: We received 555 completed questionnaires, which is estimated to be 25% of the total number of Dutch children with DM. The control group consisted of 777 children. After age-matching, the questionnaires of 188 DM patients were used. Symptoms of asthma, hayfever and eczema were reported less in the group of children with DM compared with the control group (wheeze last year, OR 0.796, 95% CI 0.408-1.554; hayfever symptoms last year, OR 0.642, 95% CI 0.369-1.118; eczema symptoms last year, OR 0.693, 95% CI 0.430-1.115). CONCLUSION: The lower prevalence of astma, hayfever and eczema symptoms in DM patients compared with age-matched controls, although not statistically significant, is consistent with the Th1/Th 2 concept.

Asthma↗
PubMed2002

The effect of brief neonatal exposure to cows' milk on atopic symptoms up to age 5.

AIMS: To determine the effect of brief early exposure to cows' milk on the expression of atopy during the first five years of life. METHODS: Follow up analysis of a double blind, placebo controlled, randomised feeding intervention trial (BOKAAL study). Subjects were 1108 children from 1533 initially randomised breast fed neonates in the Netherlands. Atopic disease and prevalence of allergic symptoms at age 1, 2, and 5, and specific IgE at age 1 and 5 were determined. RESULTS: Atopic disease in the first year was found in 10.0% (cows' milk) versus 9.3% (placebo) of the children, with a relative risk (RR) of 1.07. No differences were found in the second year either. At age 5, atopic disease was found in 26.3% (cows' milk) versus 25.0% (placebo), RR 1.05. There was no difference in the prevalence of allergic symptoms. Specific IgE to cows' milk (RAST positive 2+ or more) was 5.8% (cows' milk) versus 4.1% (placebo) at age 1 (RR 1.43), and 5.3% versus 3.0% at age 5 (RR 1.77). There was no difference in sensitisation to other common allergens between the two groups. CONCLUSION: Early, brief exposure to cows' milk in breast fed children is not associated with atopic disease or allergic symptoms up to age 5.

Animals↗
PubMed2002

Early respiratory and skin symptoms in relation to ethnic background: the importance of socioeconomic status; the PIAMA study.

AIMS: To evaluate ethnic differences in the prevalence of respiratory and skin symptoms in the first two years of life. METHODS: A total of 4146 children participated in the Prevention and Incidence of Asthma and Mite Allergy (PIAMA) study. Parents completed questionnaires on respiratory and skin symptoms, ethnic background, and other potential confounders during pregnancy, and at 3 months, 1 year, and 2 years of age. RESULTS: In the first year, "non-Dutch" children (compared with "Dutch" children) had a higher prevalence of runny nose with itchy/watery eyes (11.0% versus 5.0%). In the second year, a higher prevalence of wheeze at least once (26.7% versus 18.5%), night cough without a cold (24.6% versus 15.5%), runny nose without a cold (34.1% versus 21.3%), and runny nose with itchy/watery eyes (13.7% versus 4.6%) was found. Adjustment for various confounders, especially adjustment for socioeconomic factors, reduced most associations between ethnicity and respiratory symptoms. Only runny nose with itchy/watery eyes in the second year of life was independently associated with non-Dutch ethnicity (adjusted odds ratio 2.89, 95% CI 1.3-6.4). CONCLUSIONS: Non-Dutch children more often had respiratory symptoms in the first two years of life than Dutch children. This could largely be explained by differences in socioeconomic status. Follow up of the cohort will determine whether this higher prevalence of respiratory symptoms in children with non-Dutch ethnicity represents an increased risk of developing allergic disease rather than non-specific or infection related respiratory symptoms.

Adult↗
PubMed2002

Associations between markers of respiratory morbidity in European children.

School-aged children often experience acute respiratory symptoms. In a multicentre European study, the association between chronic respiratory symptoms (reported in a questionnaire), skin-prick test results, and lung function, and the occurrence of acute respiratory morbidity, was examined among children aged 6-12 yrs with chronic respiratory symptoms. Children with chronic respiratory symptoms, living in 10 European countries, were selected from a parent-completed questionnaire (n=4,307). Atopy was measured with skin-prick tests, and lung function with spirometry. A total of 1,854 (86% of those in the initial cohort) children kept a successful daily diary regarding their respiratory symptoms for 2-3 months. In multivariate logistic regression analyses, children with asthmatic symptoms, particularly those with doctor-diagnosed asthma, had a greater risk of occurrence of lower respiratory symptoms (odds ratio (OR): 6.12; 95% confidence interval (CI): 4.99-8.35) than children with a dry nocturnal cough as their only symptom. Atopy, particularly a positive reaction to indoor allergens, was significantly associated with occurrence of lower respiratory symptoms. For atopy the OR was 1.62 (95% CI: 1.34-1.96). A reduced level of maximal mid-expiratory flow was associated with an increased risk of lower respiratory symptoms, cough and phlegm. The associations were similar in Scandinavia, Central Eastern, Western and Southern Europe. To conclude, asthmatic symptoms reported in a questionnaire, atopic status and a reduced level of maximal mid-expiratory flow were associated with the occurrence of acute respiratory symptoms, especially those of lower respiratory symptoms.

Acute Disease↗
PubMed2002

Respiratory symptoms, bronchitis and asthma in children of Central and Eastern Europe.

The multicentre Central European Study of Air Pollution and Respiratory Health (CESAR) aimed to measure the respiratory health of schoolchildren using a standardised questionnaire in six countries of Central and Eastern Europe (CEE), allowing comparisons within this region and with other European countries. A cross-sectional study was conducted in 25 urban areas of Bulgaria, Czech Republic, Hungary, Poland, Romania, and Slovakia in 1996. Parents of 21,743 schoolchildren of age 7-11 yrs completed a questionnaire based on items from the World Health Organization and International Study of Asthma and Allergies in Childhood questions on cough and wheeze symptoms, as well as on diagnoses by doctors. Life-time prevalence of bronchitis was 55.9%, asthma 3.9%, and asthmatic, spastic or obstructive bronchitis 12.3%. In CEE countries the prevalence of bronchitis is higher and prevalence of asthma appears lower than in Western Europe. However, if asthma is defined as a diagnosis of either asthma or asthmatic, spastic or obstructive bronchitis, then its prevalence is comparable to Western Europe, or higher. In this region, within-country variation for most respiratory parameters is less than between-country variation. Between-country comparisons in doctors' diagnoses appear dependent on the choice of definition of asthma. Europe-wide comparisons in prevalence of respiratory symptoms and diagnosis are reported in this study. Some of the East-West difference in asthma prevalence may be attributable to differences in diagnostic practice.

Acute Disease↗
PubMed2002

Traffic-related air pollution and respiratory health during the first 2 yrs of life.

As part of an international collaborative study on the impact of Traffic-Related Air Pollution on Childhood Asthma (TRAPCA), the health effects associated with long-term exposure to particles with a 50% cut-off aerodynamic diameter of 2.5 microm (PM2.5), PM2.5 absorbance, and nitrogen dioxide (NO2) were analysed. The German part of the TRAPCA study used data from subpopulations of two ongoing birth cohort studies (German Infant Nutrition Intervention Programme (GINI) and Influences of Lifestyle Related Factors on the Human Immune System and Development of Allergies in Children (LISA)) based in the city of Munich. Geographic information systems (GIS)-based exposure modelling was used to estimate traffic-related air pollutants at the birth addresses of 1,756 infants. Logistic regression was used to analyse possible health effects and potential confounding factors were adjusted for. The ranges in estimated exposures to PM2.5, PM2.5 absorbance, and NO2 were 11.9-21.9 microg m(-3), 1.38-4.39 x 10(-5) m(-1), and 19.5-66.9 microg x m3, respectively. Significant associations between these pollutants and cough without infection (odds ratio (OR) (95% confidence interval (CI)): 1.34 (1.11-1.61), 1.32 (1.10-1.59), and 1.40 (1.12-1.75), respectively) and dry cough at night (OR (95% CI): 1.31 (1.07-1.60), 1.27 (1.04-1.55), and 1.36 (1.07-1.74), respectively) in the first year of life were found. In the second year of life, these effects were attenuated. There was some indication of an association between traffic-related air pollution and symptoms of cough. Due to the very young age of the infants, it was too early to draw definitive conclusions from this for the development of asthma.

Air Pollution↗
PubMed2001

Definition of respiratory symptoms and disease in early childhood in large prospective birth cohort studies that predict the development of asthma.

We have reviewed the prospective value of early respiratory symptoms for determining the risk of development of asthma later in life by using data from studies based on the general population, hospital population, and general practices. Although "wheezing" in infancy generally has a good prognosis, it is an important risk factor for the development of asthma later in life. The prognostic value of "coughing" and "shortness of breath" in infancy for the later development of asthma is less clear. Despite the fact that no internationally accepted criteria for the definition of asthma in early childhood are available, many studies have been performed on this topic. We also investigated the outcome variables that were used to describe respiratory symptoms and disease in early childhood in the publications of nine large prospective birth cohort studies on the development of asthma. From seven of these studies, we reviewed the original questionnaires. We found that various studies used different outcome variables, but the data actually collected were similar. This is an important observation because it implies that comparisons between studies can be markedly improved by data sharing among investigators.

Asthma↗
PubMed2001

Fungal extracellular polysaccharides, beta (1-->3)-glucans and culturable fungi in repeated sampling of house dust.

Fungal exposure inside homes has been associated with adverse respiratory symptoms in children and adults. While fungal assessment has traditionally relied upon questionnaires, fungal growth on culture plates and spore counts, new immunoassays for extracellular polysaccharides (EPS) and beta (1-->3)-glucans have enabled quantitation of fungal agents in house dust in a more timely and cost-effective manner, possibly providing a better measure of fungal exposure. We investigated associations among measurements of EPS, beta (1-->3)-glucans and culturable fungi obtained from 23 Dutch homes. From each home, dust samples were vacuumed from the living room floor twice during the Fall, Winter and Spring seasons for a total of six collections (every 6 weeks from October 1997 to May 1998). Samples were sieved and fine dust was analyzed for EPS from Aspergillus and Penicillium spp. combined, beta (1-->3)-glucans and culturable fungi. EPS was positively associated with glucan; an increase from the 25th to the 75th percentile of glucan concentration was associated with a 1.6-fold increase in EPS concentration (95% CI = 1.3 to 2.0; p < 0.01). The most significant variables associated with EPS and glucan concentrations were the surface type that was vacuumed and the concentration of total culturable fungi (in colony forming units (CFU)/g dust), with an increase in CFU/g from the 25th to the 75th percentile associated with a 1.3 (1.1-1.6)-fold increase in glucan and a 1.7 (1.3-2.2)-fold increase in EPS concentrations. In addition, the within-home variation of EPS levels were smaller than those between homes (25,646 U/g vs. 50,635 U/g), whereas the variation of glucan levels was similar within and between homes (1,300 vs. 1,205 micrograms/g). These positive associations suggest that house dust concentrations of beta (1-->3)-glucan, and particularly those of EPS, are good markers for the overall levels of fungal concentrations in floor dust which is a surrogate for estimating airborne fungal exposure.

Adult↗
PubMed2001

Are children at high familial risk of developing allergy born into a low risk environment? The PIAMA Birth Cohort Study. Prevention and Incidence of Asthma and Mite Allergy.

BACKGROUND: A family history of allergy, reflecting genetic risk factors, increases the risk of developing allergic diseases, but environmental factors, especially those present in early life, also contribute to the actual development of allergic phenomena. OBJECTIVE: To identify differences in lifestyle between allergic and non-allergic parents, which may influence the prevalence of environmental risk factors in their homes. METHODS: Data were collected in a Dutch birth cohort study by postal questionnaire about 2 months before and 3 months after the birth of the child. RESULTS: Of the 3147 infants in the study 1910 (61%) had two non-allergic parents, of 315 infants (10%) only the mother was allergic, of 787 infants (25%) only the father was allergic and 135 (4%) infants had two allergic parents. If both parents were allergic, 53% reported that allergy was taken into consideration when they furnished their home and significantly more of their homes were free of cats and free of cigarette smoke; adjusted odds ratio's for two allergic parents vs. two non-allergic parents were 0.30 (confidence interval (CI) 0.17-0.50) for the presence of cats and 0.46 (CI 0.27-0.75) for smoking in the home. Parental allergy was also associated with having a smooth floor in the baby's bedroom and with postponement of the introduction of fruits and vegetables until the age of 26 weeks. The presence of dogs at home, the prevalence of mothers' smoking during pregnancy and the decision to breast feed were unrelated to parental allergy. CONCLUSION: We conclude that studies on the relationship between allergy in parents and allergy in their offspring should always consider the home environment as a potential confounder. For allergy prevention our results imply that among allergic parents there is awareness and willingness to take measures that reduce exposure to indoor allergens.

Animals↗
PubMed2001

Increased occurrence of asthma and allergy: critical appraisal of studies using allergic sensitization, bronchial hyper-responsiveness and lung function measurements.

BACKGROUND: Many studies have reported an increase in the occurrence of asthma and respiratory allergies in recent decades, but this increase is mostly based on studies using rather subjective measurements of asthma and allergies, such as questionnaires and doctor's diagnosis. None of the reviews specifically focused on studies using more 'objective' measurements, such as sensitization (specific IgE or skin prick testing (SPT)), bronchial hyper-responsiveness (BHR) or lung function (LF). OBJECTIVE: To review articles studying a time trend of occurrence of these 'more objective' measurements. METHODS: A MEDLINE-search (1966-February 2000) was performed. The following criteria were used: population-based, using IgE, SPT, BHR or LF measurements in the same age-group at least twice, with at least 2 years between and using similar methods. RESULTS: The MEDLINE-search resulted in only 16 articles, performed in 13 populations in seven different countries. Nine articles used the same objective measurements twice in the whole population. Three of these reported a non-significant increase or decrease. The other six articles found a significant increase in at least one objective measurement and of these only three reported a consistent significant increase. CONCLUSIONS: The increase in the occurrence of reported asthma and allergy is supported by only a few articles confirming these results with 'more objective measurements'.

Adolescent↗