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Biomedical subjects

G Hoek

Publications and source records attributed to G Hoek.

At least 19 recordsLinked to original sources
PubMed2006

Comparison of parental reports of smoking and residential air nicotine concentrations in children.

BACKGROUND: Using questionnaires to assess children's residential exposure to environmental tobacco smoke (ETS) may result in misclassification from recall and response bias. Questionnaire data have frequently been validated against urinary cotinine measurements, but rarely against actual measurements of residential air nicotine. OBJECTIVE: To compare questionnaire reported smoking with air nicotine concentrations in a large population of children and with urinary cotinine levels in a subpopulation; and to assess the potential impact of the symptom status of the children on the agreement between different measures of exposure. METHODS: The authors assessed residential exposure to ETS in 347 German, 335 Dutch, and 354 Swedish preschool and schoolchildren by questionnaire and air nicotine measurements, and in a subset of 307 German children by urinary cotinine measurements. They then compared the different measures of ETS exposure. RESULTS: In all countries, air nicotine concentrations increased with increasing questionnaire reported smoking in a dose-response fashion. Specificity and negative predictive values of questionnaire reports for nicotine concentrations were excellent. Sensitivity and positive predictive values were moderate to good. Excluding occasional smokers, the overall percentage of homes misclassified was 6.9%, 6.7%, and 5.1% in Germany, the Netherlands, and Sweden, respectively. Similar results were found for the agreement of urinary cotinine concentrations with questionnaire reports and air nicotine levels. There was no indication of underreporting by parents of symptomatic children. CONCLUSION: Despite some misclassification, questionnaire reports are an inexpensive and valid estimate of residential ETS exposure among preschool and school children.

Adult↗
PubMed2006

NO2 and children's respiratory symptoms in the PATY study.

OBJECTIVES: NO2)is a major urban air pollutant. Previously reported associations between ambient NO2)and children's respiratory health have been inconsistent, and independent effects of correlated pollutants hard to assess. The authors examined effects of NO2 on a spectrum of 11 respiratory symptoms, controlling for PM10 and SO2, using a large pooled dataset. METHODS: Cross sectional studies were conducted in Russia, Austria, Italy, Switzerland, and the Netherlands, during 1993-99, contributing in total 23 955 children. Study-specific odds ratios for associations with ambient NO2 are estimated using logistic regressions with area-level random effects. Heterogeneity between study-specific results, and mean estimates (allowing for heterogeneity) are calculated. RESULTS: Long term average NO2 concentrations were unrelated to prevalences of bronchitis or asthma. Associations were found for sensitivity to inhaled allergens and allergy to pets, with mean odds ratios around 1.14 per 10 microg/m3 NO2. SO2 had little confounding effect, but an initial association between NO2 and morning cough was reduced after controlling for PM10. Associations with reported allergy were not reduced by adjustment for the other pollutants. Odds ratios for allergic symptoms tended to be higher for the 9-12 year old children compared with the 6-8 year old children. CONCLUSIONS: Evidence for associations between NO2 and respiratory symptoms was robust only for inhalation allergies. NO2 most likely is acting as an indicator of traffic related air pollutants, though its direct effect cannot be ruled out. This remains important, as policies to reduce traffic related air pollution will not result in rapid reductions.

Air Pollutants↗
PubMed2006

Parental education and children's respiratory and allergic symptoms in the Pollution and the Young (PATY) study.

Inequalities in health between socio-economic groups are a major public health concern. The current authors studied associations between parental socio-economic status (SES) and children's respiratory and allergic symptoms in 13 diverse countries, including the Russian Federation, North America (Canada and the USA), and countries across Eastern and Western Europe. Data of 57,000 children aged 6-12 yrs, originating from eight cross-sectional studies, were analysed. SES was defined by parental education. Respiratory and allergic symptoms were defined by parental questionnaire reports. Multiple logistic regressions showed that low parental education was associated with a decreased risk of inhalant allergy and itchy rash in school children. Furthermore, low parental education was associated with an increased prevalence of wheeze and nocturnal dry cough. No clear association was found between parental education and prevalence of doctor-diagnosed asthma and bronchitis. Part of the difference between socio-economic groups with regard to their children's symptoms was explained by established risk factors, such as parental allergy, smoking during pregnancy, pet ownership, crowding, mould/moisture in the home, use of gas for cooking, and air pollution (particulate matter with a diameter of <10 microm). However, differences remained after adjusting for these variables. Children's health was associated with parental education. The association could not fully be explained by established risk factors.

Asthma↗
PubMed2005

DNA repair polymorphisms and cancer risk in non-smokers in a cohort study.

Environmental carcinogens contained in air pollution, such as polycyclic aromatic hydrocarbons, aromatic amines or N-nitroso compounds, predominantly form DNA adducts but can also generate interstrand cross-links and reactive oxygen species. If unrepaired, such lesions increase the risk of somatic mutations and cancer. Our study investigated the relationships between 22 polymorphisms (and their haplotypes) in 16 DNA repair genes belonging to different repair pathways in 1094 controls and 567 cancer cases (bladder cancer, 131; lung cancer, 134; oral-pharyngeal cancer, 41; laryngeal cancer, 47; leukaemia, 179; death from emphysema and chronic obstructive pulmonary disease, 84). The design was a case-control study nested within a prospective investigation. Among the many comparisons, few polymorphisms were associated with the diseases at the univariate analysis: XRCC1-399 Gln/Gln variant homozygotes [odds ratios (OR) = 2.20, 95% confidence intervals (CI) = 1.16-4.17] and XRCC3-241 Met/Met homozygotes (OR = 0.51, 95% CI = 0.27-0.96) and leukaemia. The recessive model in the stepwise multivariate analysis revealed a possible protective effect of XRCC1-399Gln/Gln in lung cancer (OR = 0.22, 95% CI = 0.05-0.98), and confirmed an opposite effect (OR = 2.47, 95% CI = 1.02-6.02) in the leukaemia group. Our results also suggest that the XPD/ERCC1-GAT haplotype may modulate leukaemia (OR = 1.28, 95% CI = 1.02-1.61), bladder cancer (OR = 1.38, 95% CI = 1.06-1.79) and possibly other cancer risks. Further investigations of the combined effects of polymorphisms within these DNA repair genes, smoking and other risk factors may help to clarify the influence of genetic variation in the carcinogenic process.

Adult↗
PubMed2005

Sources and elemental composition of ambient PM(2.5) in three European cities.

Source apportionment of urban fine particle mass (PM(2.5)) was performed from data collected during 1998-1999 in Amsterdam (The Netherlands), Erfurt (Germany) and Helsinki (Finland), using principal component analysis (PCA) and multiple linear regression. Six source categories of PM(2.5) were identified in Amsterdam. They were traffic-related particles (30% of the average PM(2.5)), secondary particles (34%), crustal material (7%), oil combustion (11%), industrial and incineration processes (9%), and sea salt (2%). The unidentified PM(2.5) fraction was 7% on the average. In Erfurt, four source categories were extracted with some difficulties in interpretation of source profiles. They were combustion emissions related to traffic (32%), secondary PM (32%), crustal material (21%) and industrial processes (8%). In Erfurt, 3% of PM(2.5) remained unidentified. Air pollution data and source apportionment results from the two Central European cities were compared to previously published results from Helsinki, where about 80% of average PM(2.5) was attributed to transboundary air pollution and particles from traffic and other regional combustion sources. Our results indicate that secondary particles and local combustion processes (mainly traffic) were the most important source categories in all cities; their impact on the average PM(2.5) was almost equal in Amsterdam and Erfurt whereas, in Helsinki, secondary particles made up for as much as half of the total average PM(2.5).

Air Pollution↗
PubMed2005

Associations between ambient, personal, and indoor exposure to fine particulate matter constituents in Dutch and Finnish panels of cardiovascular patients.

AIMS: To assess the relation between ambient, indoor, and personal levels of PM2.5 and its elemental composition for elderly subjects with cardiovascular disease. METHODS: In the framework of a European Union funded study, panel studies were conducted in Amsterdam, the Netherlands and Helsinki, Finland. Outdoor PM2.5 concentrations were measured at a fixed site. Each subject's indoor and personal PM2.5 exposure was measured biweekly for six months, during the 24 hour period preceding intensive health measurements. The absorbance of PM2.5 filters was measured as a marker for diesel exhaust. The elemental content of more than 50% of the personal and indoor samples and all corresponding outdoor samples was measured using energy dispersive x ray fluorescence. RESULTS: For Amsterdam and Helsinki respectively, a total of 225 and 238 personal, and 220 and 233 indoor measurements, were analysed from 36 and 46 subjects. For most elements, personal and indoor concentrations were lower than and highly correlated with outdoor concentrations. The highest correlations (median r>0.9) were found for sulfur and particle absorbance, which both represent fine mode particles from outdoor origin. Low correlations were observed for elements that represent the coarser part of the PM2.5 particles (Ca, Cu, Si, Cl). CONCLUSIONS: The findings of this study provide support for using fixed site measurements as a measure of exposure to particulate matter in time series studies linking the day to day variation in particulate matter to the day to day variation in health endpoints, especially for components of particulate matter that are generally associated with fine particles and have few indoor sources. The high correlation for absorbance of PM2.5 documents that this applies to particulate matter from combustion sources, such as diesel vehicles, as well.

Aged↗
PubMed2005

Exposure to traffic related air pollutants: self reported traffic intensity versus GIS modelled exposure.

BACKGROUND: In epidemiological studies of the potential health effects of traffic related air pollution, self reported traffic intensity is a commonly used, but rarely validated, exposure variable. METHODS: As part of a study on the impact of Traffic Related Air Pollution on Childhood Asthma (TRAPCA), data from 2633 and 673 infants from the Dutch and the German-Munich cohorts, respectively, were available. Parents subjectively assessed traffic intensity at the home address. Objective exposures were estimated by a combination of spatial air pollution measurements and geographic information system (GIS) based modelling using an identical method for both cohorts. RESULTS: The agreement rates between self reported and GIS modelled exposure--accumulated over the three strata of self assessed traffic intensity--were 55-58% for PM(2.5), filter absorbance (PM(2.5) abs), and nitrogen dioxide in Munich and 39-40% in the Netherlands. Of the self reported low traffic exposed group, 71-73% in Munich and 45-47% in the Netherlands had low modelled exposure to these three air pollutants. Of the self assessed high exposed subgroups in Munich (15% of the total population) and the Netherlands (22% of the total population), only 22-33% and 30-32% respectively had high modelled exposure to the three air pollutants. The subjective assessments tend to overestimate the modelled estimates for PM(2.5) and NO2 in both study areas. When analysis was restricted to the portion of the Dutch cohort living in non-urban areas, the agreement rates were even lower. CONCLUSIONS: Self reported and modelled assessment of exposure to air pollutants are only weakly associated.

Adult↗
PubMed2005

Susceptibility to air pollution in elderly males and females.

It is important to know which individuals in the general population have increased susceptibility to air pollution. The aim of this study was to identify susceptible subgroups by studying airways hyperresponsiveness (AHR), high total immunoglobulin (Ig)E and sex. Diary data on lower and upper respiratory symptoms (LRS and URS, respectively), cough, and morning and evening peak expiratory flow (PEF) were collected in 327 elderly patients (50-70 yrs) for a period of 3 months. Acute effects of particulate matter with a diameter <10 microm, black smoke, sulphur dioxide and nitrogen dioxide on symptoms and PEF were estimated using logistic regression. In total, 48 (14.7%) subjects had AHR+/IgE+, 112 (34.3%) had AHR-/IgE+, 42 (12.8%) had AHR+/IgE- and 125 (38.2%) had AHR-/IgE-. In the AHR+/IgE+ group, each 10 microg x m(-3) increase in air pollution was associated with a significant increase in prevalence of URS (odds ratio ranging 1.03-1.19), cough (1.03-1.08) and fall in morning PEF (1.04-1.26). In the AHR+/IgE+ group, males responded predominantly with symptoms and females with a fall in morning PEF. In conclusion, elderly individuals with both airway hyperresponsiveness and high total immunoglobulin E are especially susceptible to air pollution. Identifying susceptible subgroups might enlarge insight into the actual mechanisms by which air pollution evokes specific modes of response.

Age Factors↗
PubMed2004

Daily variation in fine and ultrafine particulate air pollution and urinary concentrations of lung Clara cell protein CC16.

BACKGROUND: Daily variations in ambient particulate air pollution have been associated with respiratory mortality and morbidity. AIMS: To assess the associations between urinary concentration of lung Clara cell protein CC16, a marker for lung damage, and daily variation in fine and ultrafine particulate air pollution. METHODS: Spot urinary samples (n = 1249) were collected biweekly for six months in subjects with coronary heart disease in Amsterdam, Netherlands (n = 37), Erfurt, Germany (n = 47), and Helsinki, Finland (n = 47). Ambient particulate air pollution was monitored at a central site in each city. RESULTS: The mean 24 hour number concentration of ultrafine particles was 17.3x10(3) cm(-3) in Amsterdam, 21.1x10(3) cm(-3) in Erfurt, and 17.0x10(3) cm(-3) in Helsinki. The mean 24 hour PM2.5 concentrations were 20, 23, and 13 microg/m3, respectively. Daily variation in ultrafine particle levels was not associated with CC16. In contrast, CC16 concentration seemed to increase with increasing levels of PM2.5 in Helsinki, especially among subjects with lung disorders. No clear associations were observed in Amsterdam and Erfurt. In Helsinki, the CC16 concentration increased by 20.2% (95% CI 6.9 to 33.5) per 10 microg/m3 increase in PM2.5 concentration (lag 2). The respective pooled effect estimate was 2.1% (95% CI -1.3 to 5.6). CONCLUSION: The results suggest that exposure to particulate air pollution may lead to increased epithelial barrier permeability in lungs.

Aged↗
PubMed2003

Effects of fine and ultrafine particles on cardiorespiratory symptoms in elderly subjects with coronary heart disease: the ULTRA study.

The ULTRA Study, a study investigating the association between fine and ultrafine particulate air pollution and cardiorespiratory health, was conducted during the winter of 1998-1999 in Amsterdam, the Netherlands; Erfurt, Germany; and Helsinki, Finland. At each study center, a panel of elderly subjects with coronary heart disease recorded cardiac and respiratory symptoms in a diary. Exposure to ambient air pollution was characterized by measuring daily mass concentrations of particles smaller than 10 micro m (PM(10)) and 2.5 micro m (PM(2.5)), number concentrations of ultrafine particles (NC(0.01-0.1)), and gases. Odds ratios for the relation of symptoms to air pollution, adjusted for time trend, respiratory infections, and meteorologic variables, were mostly homogeneous across the centers. No association was found between air pollution and chest pain. A 10- micro g/m(3) increase in PM(2.5) was positively associated with the incidence of shortness of breath (odds ratio (OR) = 1.12, 95% confidence interval (CI): 1.02, 1.24) and with avoidance of activities (OR = 1.09, 95% CI: 0.97, 1.22). NC(0.01-0.1) was only associated with the prevalence of avoidance of activities (OR = 1.10, 95% CI: 1.01, 1.19). In conclusion, PM(2.5) was associated with some cardiac symptoms in three panels of elderly subjects. PM(2.5 )was more strongly related to cardiorespiratory symptoms than ultrafine particles were.

Aged↗
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↗
PubMed2001

The association between air pollution and heart failure, arrhythmia, embolism, thrombosis, and other cardiovascular causes of death in a time series study.

In a time series study, air pollution was associated with specific cardiovascular causes of death. Deaths due to heart failure (ICD-9 428), arrhythmia (ICD-9 427), cerebrovascular causes (ICD-9 430-436), and thrombocytic causes (ICD-9 415.1, 433-4, 444, 452-3) were more strongly associated with air pollution than cardiovascular deaths (ICD-9 390-448) in general. Excess relative risks were 2.5 to 4 times larger for these categories than for total cardiovascular disease mortality. Heart failure deaths, which made up 10% of all cardiovascular deaths, were found to be responsible for about 30% of the cardiovascular deaths related to particulate matter, SO2, CO, and NO2.

Adult↗
PubMed2000

Incidence of influenza-like illness, measured by a general practitioner sentinel system, is associated with day-to-day variations in respiratory health in panel studies.

During three consecutive winters beginning in 1992-1993, the association between the incidence of influenza and influenza-like illness (ILI), measured by a general practitioner sentinel system, and respiratory health was investigated in an air pollution panel study. Data from 22 panels of children (7-11 years old) and adults (50-70 years old) in the Netherlands were used. ILI incidence was associated with peak expiratory flow, respiratory symptoms, and bronchodilator use. Peak ILI incidence of 122 cases/10,000 subjects was associated with a decrement in peak expiratory flow of 6% and a 3- to 4.5-fold increase in symptom reporting and bronchodilator use. In panel studies, ILI incidence might be used to adjust for confounding by acute respiratory infections.

Aged↗
PubMed2000

Upper limb tension tests as tools in the diagnosis of nerve and plexus lesions. Anatomical and biomechanical aspects.

OBJECTIVE: To analyse the validity of nerve tension tests used in the diagnosis of nerve (root) and plexus lesions of the upper extremity. DESIGN: In six arms of embalmed human bodies, in situ measurements were performed to assess the effect of nerve tension tests on the median, ulnar and radial nerves and the cords of the brachial plexus. BACKGROUND: In clinical practice it is useful to have fast, easy and cheap tests for the diagnosis of nerve (root) lesions of the upper extremity, analogous to Lasègue's Straight Leg Raising test.Methods. The Upper Limb Tension Tests for the median, ulnar and radial nerves, as well as the Upper Limb Tension Tests combined with contralateral rotation and lateral bend of the cervical spine (Upper Limb Tension Test+) were used to generate tension to these nerves. Buckle force transducers were used to assess tensile forces in the nerves and in the medial, lateral and posterior cords of the brachial plexus. RESULTS: Nerve tension introduced in the distal part of the median, ulnar and radial nerves was transmitted upward to the cords of the brachial plexus. Exclusively the median nerve Upper Limb Tension Test and Upper Limb Tension Test+ turned out to be sensitive and specific tension tests. Mechanical tension caused by the Upper Limb Tension Test+ was not significantly higher than that caused by the Upper Limb Tension Tests. The Upper Limb Tension Tests cannot be used to selectively stress cervical nerve roots. The findings justify investigation of exclusively the median nerve Upper Limb Tension Test and Upper Limb Tension Test+ on their clinical validity. RELEVANCE: Before nerve tension tests for the median, ulnar and radial nerves can be introduced to clinical practice it is necessary to assess their validity quantitatively.

Arm↗
PubMed2000

PM10 elemental composition and acute respiratory health effects in European children (PEACE project). Pollution Effects on Asthmatic Children in Europe.

The ability of particles with a 50% cut-off aerodynamic diameter of 10 microm (PM10) to cause respiratory health effects possibly depends on their composition. This study evaluated whether the soluble elemental concentrations in PM10 were related to acute respiratory health effects. The Pollution Effects on Asthmatic Children in Europe (PEACE) study is a multicentre study of the acute effects of PM10 and other air pollution components on the respiratory health of children with chronic respiratory symptoms in urban and suburban panels. Children, 1208, divided among 17 panels were followed for > or =2 months. Exposure to air pollution was monitored on a daily basis. Health status was monitored by twice daily peak expiratory flow (PEF) measurements and a symptom diary. Median concentrations of iron ranged 105-1,110 ng x m(-3) in the urban and 32-517 ng x m(-3) in the suburban locations. The daily concentrations of most elements were not associated with daily variation in PEF, prevalence of respiratory symptoms or bronchodilator use. Silicon and iron concentrations tended to be negatively associated with PEF, and positively associated with the prevalence of phlegm. In two pollutant models, PM10 effect-estimates on phlegm prevalence were reduced and lost significance, whereas the effect-estimates of iron or silicon remained essentially unchanged. The effects of silicon and iron could not be separated. In conclusion, this study provides only weak support for the hypothesis that daily fluctuations in soluble elemental concentrations in ambient particulate matter are responsible for acute health effects.

Air Pollution↗
PubMed2000

Acute effects of air pollution on respiratory health of 50-70 yr old adults.

The aim of this study was to investigate the association between daily changes in respiratory health and air pollution in 489 adults, aged 50-70 yrs, with and without chronic respiratory symptoms, living in urban and nonurban areas in the Netherlands. Subjects were selected from the general population with a screening questionnaire. During three consecutive winters starting in 1992/1993, peak expiratory flow (PEF) and respiratory symptoms were registered in a daily diary. Daily measurements of particles with a 50% cut-off aerodynamic diameter of 10 microm (PM10), black smoke (BS), sulphate, sulphur dioxide (SO2) and nitrogen dioxide (NO2) were conducted. The difference in PM10, BS and sulphate concentrations between urban and nonurban areas was small, but there was more contrast in the concentrations of SO2 and NO2. In symptomatic subjects from urban areas, PM10, BS, sulphate and SO2 concentrations were associated with the prevalence of large decrements in morning PEF (>20% below the median). BS in particular was also associated with upper respiratory symptoms (URS). The magnitude of the effect estimates was in the order of an 80% increase in PEF decrements and a 20% increase in URS for a 40 microg x m-3 increase of the same day BS concentration. In symptomatic subjects from nonurban areas, no consistent associations between air pollution and health indicators were observed. However, the differences in effect estimates between urban and nonurban symptomatic panels were small and nonsignificant. In nonsymptomatic adults from both areas, no consistent pattern of associations with air pollution was found. In conclusion, air pollution effects were only found in symptomatic adults in the urban areas.

Age Distribution↗