Childhood diet and asthma and atopy at 8 years of age: the PIAMA birth cohort study.

Diet may affect the development of asthma. We investigated whether asthma or atopy outcomes at 8 yrs of age were associated with long-term dietary exposure, and whether associations were different for consumption at early or later age. The Prevention and Incidence of Asthma and Mite Allergy (PIAMA) birth cohort enrolled 4,146 participants at baseline, who were followed up to 8 yrs of age. Dietary intakes of interest were fruit, vegetables, brown/wholemeal bread, fish, milk, butter and margarine. Associations between food intake at early (2-3 yrs) and later (7-8 yrs) age, and long-term intake, asthma and atopy at 8 yrs of age were calculated by logistic regression. Complete longitudinal dietary data for at least one of the food groups were available for 2,870 children. Fruit consumption at early age was associated with reduced asthma symptoms (OR per 1 consumption day per week increase 0.93, 95% CI 0.85-1.00). Long-term fruit intake was inversely associated with asthma symptoms (OR 0.90, 95% CI 0.82-0.99) and sensitisation to inhaled allergens (OR 0.90, 95% CI 0.82-0.99). We found no consistent associations between diet and outcomes for other foods. This study indicates no consistent effects of increased early or late consumption, or long-term intake of certain foods on asthma and atopy in 8-yr-olds, with a possible exception for fruit.

Maternal overweight before pregnancy and asthma in offspring followed for 8 years.

OBJECTIVE: The aim of this study was to investigate the association between maternal overweight before pregnancy and offspring asthma in an ongoing birth cohort study. Maternal overweight may affect the pulmonary and immunological development of the fetus in utero because of the increased levels of inflammatory factors associated with being overweight and thereby increase the asthma risk in childhood. DESIGN: Birth cohort study with follow-up until 8 years of age. SUBJECTS: The study population included 3963 children and their mothers who participated in the Prevention and Incidence of Asthma and Mite Allergy study. MEASUREMENTS: Maternal overweight before pregnancy was defined as a body mass index (BMI) above 25 kg m(-2). Data on wheeze, dyspnea and prescription of inhaled corticosteroids of the child were reported yearly by the parents in a questionnaire. Sensitization to inhalant allergens and bronchial hyperresponsiveness (BHR) were determined at 8 years. Effect modification by predisposition for asthma in the child was tested. Data were analyzed by logistic regression and generalized estimating equations analyses. RESULTS: At 8 years, 14.4% (n=571) of the children had asthma. In total, 20.9% (n=830) of the mothers were overweight before pregnancy. In children predisposed for asthma (n=1058), maternal overweight before pregnancy was associated with an increased risk of asthma in the child at 8 years (OR=1.52, 95% CI: 1.05-2.18) after adjustment for confounding factors, birth weight and the child's BMI. No association was observed in children without a predisposition (OR=0.86, 95% CI: 0.60-1.23). There was no association with sensitization or BHR. CONCLUSION: Children with a predisposition for asthma may have a higher risk to develop asthma during childhood when their mothers are overweight before pregnancy, irrespective of the child's BMI.

Asthma at 8 years of age in children born by caesarean section.

BACKGROUND: Caesarean section might be a risk factor for asthma because of delayed microbial colonisation, but the association remains controversial. A study was undertaken to investigate prospectively whether children born by caesarean section are more at risk of having asthma in childhood and sensitisation at the age of 8 years, taking into account the allergic status of the parents. METHODS: 2917 children who participated in a birth cohort study were followed for 8 years. The definition of asthma included wheeze, dyspnoea and prescription of inhaled steroids. In a subgroup (n = 1454), serum IgE antibodies for inhalant and food allergens were measured at 8 years. RESULTS: In the total study population, 12.4% (n = 362) of the children had asthma at the age of 8 years. Caesarean section, with a total prevalence of 8.5%, was associated with an increased risk of asthma (OR 1.79; 95% CI 1.27 to 2.51). This association was stronger among predisposed children (with two allergic parents: OR 2.91; 95% CI 1.20 to 7.05; with only one: OR 1.86; 95% CI 1.12 to 3.09) than in children with non-allergic parents (OR 1.36; 95% CI 0.77 to 2.42). The association between caesarean section and sensitisation at the age of 8 years was significant only in children of non-allergic parents (OR 2.14; 95% CI 1.16 to 3.98). CONCLUSIONS: Children born by caesarean section have a higher risk of asthma than those born by vaginal delivery, particularly children of allergic parents. Caesarean section increases the risk for sensitisation to common allergens in children with non-allergic parents only.

Breast feeding, parental allergy and asthma in children followed for 8 years. The PIAMA birth cohort study.

BACKGROUND: It is unclear how the association between breast feeding and asthma develops with age of the child and how this association over time is influenced by maternal or paternal allergy. These factors--the age of the child and maternal or paternal allergy--might partly explain the conflicting results observed in cross-sectional studies. METHODS: The study population consisted of 3115 Dutch children born in 1996/1997 who participated in the PIAMA (Prevention and Incidence of Asthma and Mite Allergy) birth cohort study. Data on breast feeding and asthma (based on wheeze, dyspnoea and prescription of inhaled steroids) were collected by yearly questionnaires. At 8 years, specific immunoglobulin E (IgE) to airborne allergens and bronchial responsiveness were measured. Data were analysed by logistic regression and generalised estimating equations (GEEs), and stratified by maternal and paternal allergic status. RESULTS: 35% (n = 1081) of the children were breast fed for >16 weeks. At 8 years of age, 12.6% (n = 392) had asthma. Breast feeding (>16 weeks vs no breast feeding) was significantly associated with a lower asthma prevalence from 3 to 8 years of age, in children of both non-allergic and allergic mothers. The inverse association between breast feeding and sensitisation to airborne allergens at 8 years was non-significant. Breast feeding was not associated with bronchial hyper-responsiveness. No interaction between breast feeding and gender, maternal allergy or paternal allergy was observed in any of the associations. CONCLUSIONS: Breast feeding is associated with a lower asthma risk in children until 8 years of age without evidence of attenuation and regardless of the family history of allergy.

HbA(1c) levels in non-diabetic Dutch children aged 8-9 years: the PIAMA birth cohort study.

AIM: Glycated haemoglobin (HbA(1c)) is considered the best index of glycaemic control in established diabetes. It may also be useful in the diagnosis of diabetes and as a screening tool. Little is known about the distribution of HbA(1c) in healthy children and its predictors. The aim of this study is to describe the distribution of HbA(1c) in non-diabetic Dutch children aged 8-9 years and to investigate potential associations of HbA(1c) in this group. METHODS: HbA(1c) was measured in 788 non-diabetic children aged 8-9 years participating in the PIAMA birth cohort study. Data on parents and children were collected prospectively by questionnaires. Weight, height and waist and hip circumference of the children were measured when blood samples were taken. RESULTS: Mean (SD) HbA(1c) was 4.9 +/- 0.33%, range 3.5-6.0%. HbA(1c) was significantly higher in boys (4.9 +/- 0.31 vs. 4.9 +/- 0.33%) and in children of mothers with gestational diabetes (5.0 +/- 0.37 vs. 4.9 +/- 0.32%). We found a significant inverse association between HbA(1c) and haemoglobin (regression coefficient: -0.169 (95% CI -0.221 to -0.118), P < 0.001). HbA(1c) was not significantly associated with age, body mass index, waist circumference, parental diabetes or maternal body mass index. CONCLUSIONS: We found no significant relation between known risk factors for Type 2 diabetes and HbA(1c) at age 8-9 years. Moreover, there was a significant inverse association between haemoglobin and HbA(1c). These results suggest that HbA(1c) may not only reflect the preceding blood glucose levels, but seems to be determined by other factors as well.

Adult onset asthma and interaction between genes and active tobacco smoking: The GABRIEL consortium.

BACKGROUND: Genome-wide association studies have identified novel genetic associations for asthma, but without taking into account the role of active tobacco smoking. This study aimed to identify novel genes that interact with ever active tobacco smoking in adult onset asthma. METHODS: We performed a genome-wide interaction analysis in six studies participating in the GABRIEL consortium following two meta-analyses approaches based on 1) the overall interaction effect and 2) the genetic effect in subjects with and without smoking exposure. We performed a discovery meta-analysis including 4,057 subjects of European descent and replicated our findings in an independent cohort (LifeLines Cohort Study), including 12,475 subjects. RESULTS: First approach: 50 SNPs were selected based on an overall interaction effect at p<10-4. The most pronounced interaction effect was observed for rs9969775 on chromosome 9 (discovery meta-analysis: ORint = 0.50, p = 7.63*10-5, replication: ORint = 0.65, p = 0.02). Second approach: 35 SNPs were selected based on the overall genetic effect in exposed subjects (p <10-4). The most pronounced genetic effect was observed for rs5011804 on chromosome 12 (discovery meta-analysis ORint = 1.50, p = 1.21*10-4; replication: ORint = 1.40, p = 0.03). CONCLUSIONS: Using two genome-wide interaction approaches, we identified novel polymorphisms in non-annotated intergenic regions on chromosomes 9 and 12, that showed suggestive evidence for interaction with active tobacco smoking in the onset of adult asthma.

Adherence to guidelines to prevent cardiovascular diseases: The LifeLines cohort study.

BACKGROUND: Cardiovascular disease (CVD) is the leading cause of death worldwide. While there is indisputable evidence that statin treatment reduces the burden of CVD, undertreatment remains a concern for primary and secondary prevention. The aim of this study was to assess the use of lipid-lowering drugs (LLD) among 70,292 individuals in the Netherlands as a proxy of adherence to the national guideline for prevention and treatment of CVD. METHODS: LifeLines is a population-based prospective cohort study in the three Northern provinces of the Netherlands. At baseline, all participants completed questionnaires, and underwent a physical examination and lab testing. The national guidelines were used to assess how many participants were eligible for LLD prescription and we analysed how many indeed reported LLD use. RESULTS: For primary prevention, 77% (2515 of 3268) of those eligible for LLD treatment did not report using these drugs, while for secondary prevention this was 31% (403 of 1302). Patients with diabetes mellitus were treated best (67%) for primary prevention. Notably, of the patients with stroke, only 47% (182 of 386) reported LLD treatment. CONCLUSION: Despite clear guidelines and multiple national initiatives to improve CVD risk management, adherence to guidelines for the treatment of CVD in the Netherlands remains a major challenge. This study calls out for improving public awareness of CVD and to improve primary and secondary prevention to prevent unnecessary CVD-related morbidity and mortality.