Search PubMed⌕ Search

Biomedical subjects

C P van Schayck

Publications and source records attributed to C P van Schayck.

At least 19 recordsLinked to original sources
PubMed2006

[The hygiene hypothesis is invalid].

The hygiene hypothesis offers an interesting explanation for the recent increase in allergy. However, all the studies that support this hypothesis are observational and cohort studies, which implies that no causal relationships can be assessed with sufficient validity. Exposure to environmental allergens and infections may very well not be determined by chance but by the behaviour of the parents. Therefore, the hygiene hypothesis should not be accepted without critical reflection of the facts presented.

Allergens↗
PubMed2006

[Relationship between the composition of fine dust particles in the air and lung function in school children].

OBJECTIVE: To determine whether or not there is a relationship between the lung function of school children and the ability of fine dust particles in the air to generate radicals. DESIGN: Descriptive. METHOD: Six primary schools in locations with different traffic volumes were selected in Maastricht, the Netherlands. Air samples were taken in these schools over a period of 4 days; the concentration of fine dust was measured in the 6 pooled samples. Lung function tests were performed in children in the age of 8-13 and their parents filled out a questionnaire on the state of their children's health. RESULTS: An average of 66% of the children (184 girls and 158 boys, with an average age of 10 years (range: 8-13 years)) participated. The average FEV1 for the children from the 6 schools was not related with the total amount of fine dust particles in the air. However, a lower average FEV1 was associated with a higher radical-generating capacity in the air samples. No direct association was observed between the radical-generating capacity of the dust and the traffic intensity. CONCLUSION: There was a clear relationship between lung function and the radical-generating capacity of fine dust in the air. On the basis of these findings future guidelines could be based on chemical properties of the fine dust particles and not exclusively on the quantity of fine dust.

English Abstract↗
PubMed2006

[Recent changes in the prevalence of asthma in children].

Over the past decennia, the prevalence of asthma in children has increased worldwide. The increase in prevalence of asthma symptoms has been estimated at around 5% per year in various countries. Possible explanations are an increasing level of awareness in doctors and patients and changes in lifestyle in affluent societies. Recent data suggest that this trend has been levelling off. Recent data also suggest that in The Netherlands the situation has been stabilizing, indeed there has been a decrease in the prevalence of asthma in children. The next few years will reveal whether this situation will remain stable or the trend will show a further decrease.

Asthma↗
PubMed2006

[The treatment of asthma: indications for a change in approach].

In both children and adults with persistent asthma, treatment with an inhaled corticosteroid (ICS) is recommended. Moreover, inhaled bronchodilating agents have a clear role to play. The minimum effective dose of an ICS in the individual patient can be determined either by starting with a low dosage of ICS and increasing the dosage gradually on the basis of the symptoms (the 'step-up' approach), or by starting with a high dosage and, if the results are good, decreasing it to the pointwhere adequate control is maintained (the 'step-down' approach). In a study of the step-up approach with the ICS fluticasone, with or without salmeterol as a long-acting beta2-agonist (LABA) in adult patients with asthma, the approach with salmeterol produced the best results, namely, good asthma control in 71% of the patients and total control in 41%. In a study involving both children and adults with asthma, good results were obtained from treatment with a relatively low maintenance dose of ICS (budesonide) combined with a LABA (formoterol), whereby patients were permitted to use additional inhalations of the combination ICS and LABA. How the different therapeutic concepts result in long-term control, what the side effects are in the long term, and whether, in addition to the clinical symptoms, laboratory findings are also important as a therapeutic criterion are all unknown.

Administration, Inhalation↗
PubMed2006

A randomized controlled trial to assess the effects of reimbursing the costs of smoking cessation therapy on sustained abstinence.

AIMS: We studied whether reimbursement for smoking cessation treatment (SCT) can increase prolonged abstinence from smoking up to 2 years. SETTING, PARTICIPANTS AND DESIGN: From the general population, we recruited smokers and assigned them randomly to a control group (n = 634) or an intervention group (n = 632). For 6 months, participants in the intervention group could apply for reimbursement and received information regarding the reimbursed SCT. Participants in the control group received no reimbursement or information. MEASUREMENTS: In this follow-up study, prolonged abstinence from smoking was defined as reported being abstinent from at least 7 days before the end of reimbursement until the follow-up assessment 6 months or 2 years later. FINDINGS: At 6 months after the end of reimbursement, 18 participants in the control group (2.8%) and 35 participants (5.5%) in the intervention group reported sustained abstinence for at least 6 months [odds ratio (OR) = 2.0, 95% confidence interval (CI) 1.1-3.6]. Two years after the reimbursement period, 10 participants in the control group (1.6%) and 27 participants in the intervention group (4.3%) still reported sustained abstinence (OR = 4.1, 95% CI 1.7-10.2). The overall effectiveness of SCT increased with reimbursement and was 22% in the intervention group and 8% in the control group after 2 years. CONCLUSIONS: Reimbursement may be an effective strategy to increase the prolonged abstinence rate even after 2 years.

Adaptation, Psychological↗
PubMed2006

Association between first-degree familial predisposition of asthma and atopy (total IgE) in newborns.

BACKGROUND: It is generally thought that infants with a first-degree familial predisposition of asthma are at higher risk of developing asthma than infants without predisposition. OBJECTIVE: To investigate whether there is an association between being at high risk for developing asthma and increased level of total IgE in newborns and whether total IgE is influenced by gender, family size, birth season, maternal smoking, birth weight, gestational age, and maternal diet. METHODS: Two hundred and twenty-one high risk and 308 low-risk infants were prenatally selected in a 5-year-period. Three to 5 days after birth, the total IgE was measured in capillary heel blood. RESULTS: Data on total IgE and first-degree familial predisposition were available for 170 high-risk and 300 low-risk infants. There was a statistically significant relationship between being at high-risk (maternal asthma) and increased levels of total IgE in newborns (total IgE cut-off levels: 0.6-0.9 IU/mL (odds ratio (OR)=2.1, 95% confidence interval (CI): 1.2-3.7 to 3.0, 95% CI: 1.5-5.9)), between being born in autumn and increased levels of total IgE in newborns [total IgE cut-off levels: 0.5-0.6 IU/mL (OR=2.5, 95% CI: 1.2-5.1 to 2.5, 95% CI: 1.2-5.4)] and between maternal vitamin supplements intake and decreased levels of total IgE in newborns (total IgE cut-off level: 0.9 IU/mL (OR=0.5, 95% CI:0.3-1.0)). There was no interaction between the effects of maternal asthma and birth season on total IgE, as well as between the effects of maternal asthma and maternal vitamin supplements intake. Gender, family size, maternal smoking, birth weight, and gestational age did not influence the associations. CONCLUSION; Being at high-risk of asthma (maternal asthma) and birth season are positively associated with the presence of increased levels of total IgE at birth, whereas maternal vitamin supplements intake is negatively associated with the presence of total IgE at birth.

Adult↗
PubMed2006

Exacerbations and associated healthcare cost in patients with COPD in general practice.

BACKGROUND: Acute exacerbations are a characteristic clinical expression of chronic obstructive pulmonary disease (COPD). The objective of this study was to investigate the occurrence rate, management, and healthcare costs of exacerbations in patients with COPD in Dutch general practice. METHODS: Baseline data set from the COPD on Primary Care Treatment (COOPT) trial was used. Details on the occurrence and management of exacerbations were collected by systematic medical record review for the 2-year period preceding trial inclusion. RESULTS: The mean age of the 286 study subjects involved was 59.2 (SD 9.6) years, postbronchodilator FEV1 67.1% (SD 16.2) of predicted. Following ERS criteria, subjects suffered from: no (26%); mild (19%); moderate (40%); or severe (15%) airflow obstruction. The overall mean and median annual exacerbation rates were 0.88 (SD 0.79) and 0.5 (IQR 1.0), respectively. Exacerbation rate was not related to severity of airflow obstruction (p=0.628). Mean annual exacerbation costs per subject were 40 Euro, 53 Euro, 61 Euro and 92 Euro for the respective severity subgroups (p=0.012). The increase of costs in the more severe subgroups was mainly attributable to more physician consultations, diagnostic procedures, and prescription of reliever medication (e.g., bronchodilators, cough preparations). CONCLUSIONS: Occurrence of exacerbations did not depend on the severity of airflow obstruction, whereas the healthcare cost associated with exacerbations increased along with the severity of the disease.

Aged↗
PubMed2005

Efficacy of bupropion and nortriptyline for smoking cessation among people at risk for or with chronic obstructive pulmonary disease.

BACKGROUND: The observations that smokers with chronic obstructive pulmonary disease (COPD) are at increased risk of depression and that nicotine may have antidepressant effects and regulate mood provide a rationale for the use of antidepressant drugs for smoking cessation in patients with COPD. No clinical trial has studied the efficacy of bupropion hydrochloride and nortriptyline hydrochloride for smoking cessation in this patient population, to our knowledge. METHODS: In a placebo-controlled double-dummy randomized trial, 255 adults at risk for COPD or with COPD were prescribed sustained-release bupropion (bupropion SR) (150 mg twice daily) or nortriptyline (75 mg once daily) for 12 weeks. All patients received smoking cessation counseling. The main outcome measure was prolonged abstinence from smoking from week 4 to week 26 after the target quit date. RESULTS: The use of bupropion SR and nortriptyline resulted in higher prolonged abstinence rates compared with placebo, although only the difference between bupropion SR and placebo was statistically significant (differences with placebo, 13.1% [95% confidence interval, 1.2%-25.1%] for bupropion SR and 10.2% [95% confidence interval, -1.7% to 22.2%] for nortriptyline). In patients with COPD, bupropion SR and nortriptyline seem efficacious in achieving prolonged abstinence (differences with placebo, 18.9% [95% confidence interval, 3.6%-34.2%] for bupropion SR and 12.9% [95% confidence interval, -0.8% to 26.4%] for nortriptyline). In participants at risk for COPD, no statistically significant differences with placebo in prolonged abstinence rates were found. CONCLUSIONS: Bupropion SR treatment is an efficacious aid to smoking cessation in patients with COPD. Nortriptyline treatment seems to be a useful alternative.

Antidepressive Agents, Second-Generation↗
PubMed2005

Associations of depressive symptoms with gender, body mass index and dyspnea in primary care COPD patients.

BACKGROUND: It has been suggested that severe COPD is associated with depressive symptoms, possibly linked to exacerbations, dyspnea and hospitalisation. However, scarce data are available in primary care where most patients suffer from mild or moderate disease. OBJECTIVE: We aimed to reveal associations of depressive symptoms with demographic and clinical characteristics in mild to moderate COPD. METHODS: Cross-sectional data on lung function measurements, exacerbation frequency, dyspnea, comorbidity, smoking behaviour, body mass index (BMI), age, gender and depressive symptoms (Beck Depression Inventory) of 147 primary care patients were assessed in multiple logistic regression analyses. RESULTS: Patients suffered from mild to moderate obstruction (FEV1 63.6% pred, range 45.1% to 82.1%). Female gender (OR 4.8, 95% CI 2.1 to 10.8), BMI > 25 (OR 0.4, 95% CI 0.2 to 0.8) and current smoking (OR 2.3, 95% CI 1.01 to 5.3) were univariately associated with depressive symptoms, while in a multivariate logistic model only female gender (OR 4.0, 95% CI 1.6 to 9.9), BMI > 25 (OR 0.3, 95% CI 0.1 to 0.7) and dyspnea (OR 1.8, 95% CI 1.1 to 2.9) were independently associated with depressive symptoms. Conclusion. These data suggest that in primary care depressive symptoms in COPD seem to be related with female gender, BMI and dyspnea. In this study, lung function, exacerbation rate, smoking behaviour, age and comorbidity are not independently associated with depressive symptoms in COPD of mild to moderate severity.

Aged↗
PubMed2005

The prevalence of house dust mite (HDM) allergy and the use of HDM-impermeable bed covers in a primary care population of patients with persistent asthma in the Netherlands.

BACKGROUND: : House dust mite (HDM) allergen is one of the most common allergens to which asthma patients are sensitised. Prevalence of HDM allergy varies in the literature. Use of HDM-impermeable bed covers reduces exposure to HDM allergen. The aim of this study was to assess the prevalence of HDM allergy in a primary care population of asthma patients, as well as the use of HDM-impermeable bed covers by these patients. METHODS: : A random sample of asthma patients between 16 and 60 years old was taken from general practices. Allergy was assessed with a radio allegro sorbent test (RAST). A questionnaire was used to identify demographic characteristics and the actual use of bed covers. RESULTS: : 534 patients were invited and 160 patients participated. 53 patients not willing to participate were randomly selected to test the external validity of our findings. The sample was representative for the primary care asthma population. 48.8% of the asthma population was sensitised to HDM allergen. 25.6% of the HDM-allergic asthma patients were using HDM-impermeable bed covers. CONCLUSION: : Almost half of the patients with asthma were sensitised to HDM allergen. Only a minority of the patients used HDM-impermeable bed covers.

Journal Article↗
PubMed2005

Indoor environment and respiratory symptoms in children living in the Dutch-German borderland.

OBJECTIVE: To investigate the relation between indoor environmental risk factors and respiratory symptoms in 7-8-year-old children living in the Dutch-German borderland. METHODS: A nested case-control study was conducted among children participating in a large longitudinal study on respiratory health. Parents of all 781 children with respiratory complaints and an equal number of randomly selected controls were asked to complete a questionnaire, including questions on indoor environment. RESULTS: The parents of 1191 children (76.2%) participated. Past exposure to environmental (OR = 2.73, 95% CI 1.14-6.67) as well as in utero exposure (OR = 2.28, 95% CI 1.15-4.53) to tobacco smoke, use of an unvented geyser for water heating (OR = 3.01, 95% CI 1.21-7.56), long-term exposure to dampness (OR = 2.98, 95% CI 1.10-8.28) or pets (OR = 2.18, 95% CI 1.39-3.42) increased the risk of asthmatic symptoms in 7-8-year-old children. A middle or low socio-economic status also increased the risk of asthmatic symptoms. An inverse association with asthmatic symptoms was seen for wall-to-wall carpeting (OR = 0.57, 95% CI 0.33-0.95) and insulation measures (OR = 0.46, 95% CI 0.25-0.83). Except for the presence of an unvented geyser, these environmental risk factors also presented a risk for coughing symptoms in children. CONCLUSION: This study showed an increased risk of respiratory symptoms in children exposed to several indoor environmental risk factors.

Air Pollution, Indoor↗
PubMed2005

The validity and ethics of giving placebo in a randomized nonpharmacologic trial was evaluated.

OBJECTIVE: When studying the effects of a non-pharmacologic intervention, the choice of a control group is often difficult. In a study on the effectiveness of increased water intake on voiding dysfunction in elderly men we used an unusual design. This article addresses the internal validty and ethics of this design. STUDY DESIGN AND SETTING: The randomized trial we evaluated had a 6-month follow-up period and was carried out among 141 elderly men with moderate lower urinary tract symptoms. The experimental group was given the instruction to drink more water, the control group received placebo medication. The participants were not informed that there was a 50% chance of receiving placebo. We measured whether the prior expectations and preferences were comparable for the two study groups, whether blinding was preserved throughout the study period, and whether the participants considered this design ethical. RESULTS: Prior to randomization, patients had higher expectations for the experimental intervention, but there was not statistically significant difference in their preference. During the study period, two out of 71 patients in the control group unmasked the placebo. In general, both groups fully agreed with the informed consent procedure. CONCLUSION: This design can be considered when the effects of a non-pharmacologic interventions are studied.

Aged↗
PubMed2005

Differences in asthma diagnosis and medication use in children living in Germany and the Netherlands.

AIM: To compare diagnosis and treatment between German and Dutch children with asthmatic symptoms at the age of 5-6 and 7-8 years, and the use of anti-asthma medication at 7-8 years of age. METHODS: Parents of 4462 children participated in two surveys, in 1995 and 1997. All 465 children identified with current asthmatic symptoms at the age of 5-6 (May 1995) or at 7-8 years of age (May 1997) were sent a third more detailed questionnaire (October 1997). RESULTS: Asthma diagnosis was more prevalent in Dutch children with current asthmatic complaints (50-60%), whereas over 90% of the German children with current asthmatic complaints had been diagnosed with bronchitis. Inhaled beta(2)-agonists were more frequently used by Dutch children compared to German children (67.3% vs. 45.6% p < 0.01) as were inhaled steroids (38.9% vs. 7.0% p < 0.01). Instead, German children more often used sodium cromoglycate or nedocromil as anti-inflammatory medication as compared with Dutch children (42.1% vs. 11.5% p < 0.01). CONCLUSIONS: Differences in diagnosis rates for asthma and bronchitis between German and Dutch children most likely result from differential labelling of complaints, and probably lead to differences in treatment practice, indicating possible undertreatment of German children with inhaled steroids.

Journal Article↗
PubMed2005

Factors associated with asthma control.

The aim of this study was to evaluate which factors are associated with asthma control experienced by asthma patients. In a cross-sectional study patients aged 16-60 years with mild to moderate asthma were selected. The influence of the following factors on asthma control was studied in a multivariate model: age, gender, socioeconomic status, smoking, perceived hyperresponsiveness (PHR, responding with asthma symptoms to one or more triggers), allergy (Phadiatop), long-acting bronchodilating agents, and inhaled corticosteroids. Asthma control was measured by means of the Asthma Control Questionnaire (ACQ) as developed by Juniper. Forced expiratory volume in 1 second (FEV1) was measured by means of a portable spirometer. In this study with 311 patients, mean ACQ score was 1.39 (range 0-4.43). A stepwise backward linear regression analysis showed that low socioeconomic status (beta 0.425; p=0.001), current smoking (beta 0.555; p<0.001), high dose of inhaled corticosteroids (beta 0.364; p=0.04) and perceived hyperresponsiveness for increasing number of different triggers (PHR for 1 trigger beta 0.833; p=0.03; 2 triggers beta 0.810; p=0.03; 3 triggers beta 0.995; p=0.01; 4 triggers beta 1.131; p=0.002; 5 triggers beta 1.182; p=0.002) are independent predictors for poorer asthma control. Beside treatment with medication, stopping smoking and avoidance of triggers are factors, which may have a high impact on asthma control.

Administration, Inhalation↗
PubMed2005

Reimbursement for smoking cessation treatment may double the abstinence rate: results of a randomized trial.

AIMS: Few smokers who try to quit smoking use smoking cessation treatment (SCT), and cost could be one factor. To increase the number of successful quitters, we assessed whether financial reimbursement for SCT would encourage the use of SCT and would as a result increase the 6-month point abstinence rate. SETTING AND PARTICIPANTS: We recruited smokers aged over 18 years from a random sample of Dutch inhabitants insured by one health insurance company. INTERVENTION AND DESIGN: The smokers were assigned randomly to the intervention group (n = 632) or control group (n = 634). Respondents in the intervention group received an offer of reimbursement for nicotine replacement therapy, bupropion and behavioural counselling. No reimbursement was offered to the control group. To preclude a change of behaviour due to disappointment in the control group, we used a randomized consent design. FINDINGS: During the reimbursement period, 10.8% smokers in the intervention group reported having used SCT compared with 4.1% in the control group (OR = 2.9, 95% CI 1.8-4.7). In the intervention group, 23.4% smokers tried to stop compared with 20.8% in the control group (OR = 1.2, 95% CI 0.9-2.4). After 6 months, the biochemically validated 7-day point prevalence abstinence rate was 5.5% in the intervention group and 2.8% in the control group (OR = 2.3, 95% CI 1.2-4.1). CONCLUSIONS: Reimbursement for SCT seems efficacious in increasing the use of SCT and may double the number of successful quitters.

Adult↗
PubMed2005

Trends in the prevalence of respiratory symptoms and treatment in Dutch children over a 12 year period: results of the fourth consecutive survey.

BACKGROUND: Although there is considerable evidence that the prevalence of childhood asthma has increased over the last decades, it is not clear if this trend is still ongoing. A study was undertaken to investigate whether previously observed trends in the prevalence of respiratory symptoms, physician visits, medication use, and absence from school in Dutch children aged 8-9 years persisted in 2001. METHODS: Parents of 1154 children aged 8-9 years eligible for a routine physical examination in 2001 were asked to complete a questionnaire on the respiratory health of their child. RESULTS: In 2001, 1102 children (95.5%) participated in the survey. Similarly high response rates were obtained in the surveys of 1989, 1993 and 1997, with 1794, 1526 and 1670 children aged 8-9 years participating in the respective surveys. The decreasing trend previously observed for recent wheeze between 1989 and 1997 persisted into 2001, particularly in boys. After increasing between 1989 and 1997, the prevalence of shortness of breath with wheeze decreased between 1997 and 2001. The proportion of wheezy children using medication increased between 1989 and 2001 in boys (42.9% v 64.8%; p = 0.003), but the increase was not statistically significant in girls (34.0% v 45.7%; p = 0.096). CONCLUSION: The prevalence of recent wheeze in Dutch school children has declined steadily since 1989. The rising prevalence of medication use in symptomatic children over time may reflect better asthma control and may partly explain the concurrently decreasing trend in the prevalence of asthma symptoms in our study population.

Absenteeism↗
PubMed2005

Are patients with COPD psychologically distressed?

This study was designed to assess the level of psychological distress in a heterogeneous group of patients with chronic obstructive pulmonary disease (COPD), and compare them with the general population and psychiatric outpatients. A total of 118 patients with COPD, a random sample of 500 subjects from the general population and 500 psychiatric outpatients participated in this study. The Dutch version of the Symptom Checklist-90-Revised was used to assess general psychological distress. The sample of patients with COPD experienced significantly more psychological distress than the general population and significantly less than psychiatric outpatients. Furthermore, no significant association was found between the severity of the pulmonary disease and the level of psychological distress, although patients with severe or very severe COPD appeared to be at increased risk of depression. Lastly, the pattern of psychological complaints seems comparable in depressed patients with COPD and psychiatric outpatients. Once patients with COPD report suffering from depressive symptoms, the level of distress seems to increase to that found in psychiatric outpatients. In conclusion, in clinical settings in which psychological complaints are not routinely assessed, the Beck Depression Inventory and Symptom Checklist-90-Revised are very useful for drawing attention to depression and psychological distress.

Aged↗