Thesis (M.Nurs.)--University of Wollongong, 2006. / Typescript. Includes bibliographical references: leaf 112-119.

Thesis (M.S.)--University of Michigan, 2001. / Includes bibliographical references.

Thesis (M.P.H.)--University of Texas at El Paso, 2009. / Title from title screen. Vita. CD-ROM. Includes bibliographical references. Also available online.

Thesis (M.S.)--University of Michigan, 2001. / Includes bibliographical references.

Thesis (M.Ed.(Educational Psychology))--University of Pretoria, 2007. / Abstract in English. Includes bibliographical references. Available on the Internet via the World Wide Web.

Thesis (D.P.H.)--University of Hawaii at Manoa, 2000. / Heading on electronic reproduction: Morrow, James Walter. Includes bibliographical references (leaves 172-196). Also available on microfiche.

D.Litt. et Phil. (Psychology) / Asthma, which affects persons from early childhood to adulthood, is an old, potentially fatal, worldwide disease but still of increasing prevalence and still with no evidence that the condition can be cured. For patients whose symptoms are severe and intractable the condition can be particularly disruptive causing major changes in daily living and severely impinging upon not only the quality of the individual's life but that of the entire family as well.

Objective: Reduced maternal levels of vitamin D, E and zinc during pregnancy has been linked to the development of asthma and allergic disease in children. The birth cohort investigated if maternal dietary intake in pregnant Saudi women was associated with childhood asthma and allergic disease up to 24 months of age. Methods: One thousand six hundred and twenty four women were recruited to a prospective birth cohort from an antenatal clinic in Riyadh, Saudi Arabia. A food frequency questionnaire was used to characterize diet during pregnancy and serum micronutrient levels were measured. 1436 singleton children were followed up at 6, 12 and 24 months of age by interview administrated telephone calls. Results: Multivariate analyses revealed no associations between the primary maternal dietary nutrient intakes of vitamin E and zinc and the respiratory outcomes in the cohort children at 24 months of age. There was a borderline significant association between increasing maternal zinc intake and maternal reports of food allergy in the cohort children at 24 months. Positive associations with maternal dietary folate intake with maternally reported ‘itchy rash for at least 6 consecutive months' (OR= 2.36 p-=0.020) and any food allergies (OR= 2.18 p= 0.025). Conclusion: This study suggests no conclusive evidence that maternal intake of vitamin D, E and zinc of Saudi women may lower the risks of developing asthma and allergic disease in early childhood. However, a higher dietary intake of folate during pregnancy increased the risk of reported itchy rash, eczema and food allergy in the cohort children up to 24 months. Further follow up of the cohort will provided evidence that will support or refute whether maternal diet during pregnancy is associated with asthma and allergic disease in childhood.

The SEATON cohort comprising 2000 pregnant women recruited 1997-99 was established to test if maternal nutrition during pregnancy affects the likelihood of children developing asthma. At 32 weeks gestation mothers’ diets were assessed by food frequency questionnaire. 1,924 live singleton births comprised the birth cohort with follow-up at 6 months, 1, 2, 5 and 10 years (the latter the focus of this thesis). Children’s diets were assessed at 5 and 10 years. Their asthmatic status was assessed by International Study of Asthma and Allergies in Childhood questionnaire. Children participating at 5 or 10 years were also invited for measurement of spirometry and allergy. Cross-sectionally at 10 years 934 children (48% boys) participated by return of questionnaire, 449 also took part in the in-depth assessment. Higher maternal vitamin D intakes were associated with decreased odds of ‘doctor diagnosed asthma’, ‘wheeze ever’ and ‘wheeze in the last year’ in the children. Contrary to findings at 5 years no association between maternal vitamin E intake and asthma outcomes was seen. Longitudinally over the 10 years of the study, higher maternal vitamin D and E intakes during pregnancy were both associated with a decreased likelihood of ‘doctor diagnosed asthma’, ‘active asthma’ and ‘wheeze in the last year’ in the children. In conclusion, reduced maternal vitamin D and E intakes during pregnancy are associated with an increased likelihood of childhood asthma during the first ten years of life. Vitamin E appears to be associated with early asthma and wheeze possibly reflecting a role in affecting early airway remodelling processes. Associations with vitamin D were seen consistently over different time-points, possibly having its effect in an immunomodulatory fashion. Intervention trials are required to ascertain if intervention during pregnancy actually reduces childhood asthma rates.

Background: Over the latter half of the last century, a dramatic increase in the prevalence of asthma has been observed. Over this same period there has been a substantial increase in the prevalence of obesity, this giving credence to the hypothesis that obesity and asthma may be causally associated. Aim: The main aims of this thesis were to: i) estimate the prevalence of asthma, allergic rhinitis, and atopic eczema in primary schoolchildren in Madinah, Saudi Arabia; ii) investigate the association between childhood obesity and prevalence of asthma; and iii) investigate possible mechanisms that might explain any associations observed. Methods: I undertook a pilot study aimed at testing the feasibility of conducting a large-scale descriptive epidemiological study of asthma and associated allergic disorders. This was followed by a two-stage cross-sectional survey, which was conducted to investigate the prevalence of asthma, allergic rhinitis, and atopic eczema in a sample of 5,188 schoolchildren, aged 6-8 years using an Arabic, validated version of the International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire. Finally, I undertook an analytical study investigating the relationship between obesity and asthma. The cross-sectional study allowed for the identification of cases (i.e. those with a history of symptoms suggestive of asthma) and controls (i.e. those without a history suggestive of asthma). A sample of 632 cases and controls were recruited into a matched case-control study. Conditional logistic regression analysis, with appropriate adjustment for a range of potential confounders, was undertaken to explore the association between measures of obesity (in particular, body mass index (BMI)) and asthma. The possible aetiological roles of atopy and airway obstruction were studied by investigating the impact of sensitisation to common aeroallergens and measurements of lung function on the association between body mass index (BMI) and asthma. Results: In the pilot study, I found that the asthma, allergic rhinitis, and atopic eczema were very prevalent in children in Madinah and that further epidemiological studies were therefore likely to be feasible. The overall prevalence of children with a history of symptoms suggestive of asthma was 23.6% (95% CI: 21.3, 26.0); the prevalence among boys was estimated at 24.4% (95% CI: 22.0, 26.9) and among girls at 21.9% (95% CI: 17.4, 27.1), respectively. After adjustment for a number of possible confounders, BMI was found to be a significant predictor of the odds of asthma in both boys (OR=1.11; 95% CI: 1.03, 1.19) and girls (OR=1.38; 95% CI: 1.23, 1.56). When sensitisation to allergens was included in the analyses, the effect of BMI on the risk of asthma was no longer evident in boys (OR=1.09, 95% CI: 0.99-1.19) or girls (OR=1.25; 95% CI: 0.96-1.60). When the effect of lung function measures were factored into the model, the association however persisted: boys: OR=1.10 (95% CI: 1.02, 1.18) and girls OR=1.37 (95% CI: 1.22, 1.54). Conclusions: Asthma and related allergic disorders are very common in primary schoolchildren in Saudi Arabia. BMI is associated with symptoms suggestive of asthma in primary schoolchildren. This effect does not appear to be mediated through respiratory obstruction, but may, at least in part, be mediated through increasing the risk of allergic sensitisation. Prospective and more detailed gender-specific mechanistic studies are now needed to further investigate this association.