Theseshttp://hdl.handle.net/10034/6230422024-03-28T08:36:12Z2024-03-28T08:36:12ZDevelopment of a novel dietary assessment tool for vitamin D and the in vivo and in vitro effects of supplementation on asthmaWatkins, Stephaniehttp://hdl.handle.net/10034/6284222024-01-13T01:29:12Z2023-09-01T00:00:00ZDevelopment of a novel dietary assessment tool for vitamin D and the in vivo and in vitro effects of supplementation on asthma
Watkins, Stephanie
Vitamin D is a secosteroid hormone with the essential role of maintaining calcium and phosphorus homeostasis to support bone metabolism. Furthermore, vitamin D has also been shown to have important immunomodulatory functions, which have been linked to inflammatory diseases such as asthma. In the UK, 18.8% of the general population are vitamin D deficient during the winter. In 2016, SACN proposed recommendations that adults in the UK consume 400 IU (10 μg) vitamin D day-1.
Health and disease are linked to diet and nutrition therefore, assessing food intake is crucial. A food frequency questionnaire (FFQ) captures habitual food intake with a lower participant burden compared to alternative methods. Validation of a FFQ requires comparison of nutrient biomarkers with another method of dietary assessment. The first study in this thesis recruited 50 healthy volunteers to assess the agreement between a four-day food diary and a newly designed vitamin FFQ to measure dietary intake of vitamin D. Participants provided a blood sample for plasma analysis of 25(OH)D concentrations. Results of this
study showed a strong correlation between vitamin D intake recorded by the FFQ and the food diary (r = 0.609, p < 0.0001) within 95% limits of agreement. Our analysis suggested that this FFQ is a useful and rapid tool for researchers and health professionals to assess vitamin D dietary intakes in UK adults.
Vitamin D deficiency is linked to asthma in adults and associated with reduced lung function. Clinical trials investigating the effect of vitamin D supplementation have mainly focussed on asthmatic children and trials carried out in adults have used bolus dosing. The aim of chapter 3 was to conduct a 12-week randomised placebo-controlled trial investigating the effect of daily 5000 IU vitamin D supplementation on lung function and inflammation in 32 adults with mild to moderate asthma. The intervention resulted in a significant increase in the mean (± SD) ratio of FEV1: FVC from baseline (week 0) to post-intervention (week 12) in
the vitamin D group (+ 0.05 ± 0.06) compared to the placebo group (+ 0.006 ± 0.04, p = 0.04). This dosing strategy at a level above current UK recommendations may be a useful adjunct to existing asthma control strategies.
The Calu-3 cell line has been used as a model of asthma and the aim of chapter 4 was to investigate the effect of calcitriol and 25(OH)D treatment of Calu-3 cell cultures on cell proliferation and secretion of inflammatory biomarkers. Incubation of cultures for 24 and 72 hours respectively, with 50nM (p = 0.002; p < 0.0001), 100nM (p = 0.004; p = 0.007) and 200nM (p = 0.002; p < 0.0001) 25(OH)D resulted in significantly decreased proliferation compared to an untreated control. No effect was observed with calcitriol treatment. To our knowledge, this is the first in vitro study using the Calu-3 cell line to show differing effects of
vitamin D metabolites.
The findings from this thesis are clinically relevant in the UK in a population that is at increased risk of vitamin D deficiency during the winter months. The new tool designed and validated will facilitate easier measurement of vitamin D dietary intakes and the clinical trial and in vitro work have provided novel insights to patient outcomes and underlying mechanisms of the benefit of vitamin D supplementation to asthma patients.
2023-09-01T00:00:00ZMedication adherence among patients with heart failure in Nigeria: from the patients’ and healthcare professionals’ perspectivesOyelami, Abiola I.http://hdl.handle.net/10034/6276622023-10-01T01:36:32Z2022-06-01T00:00:00ZMedication adherence among patients with heart failure in Nigeria: from the patients’ and healthcare professionals’ perspectives
Oyelami, Abiola I.
Introduction
Although the efficacious pharmacotherapy advancements in the treatment of Heart Failure (HF) have been widely documented, mortality rates and hospitalisation rates among patients with HF remain high. An important reason for recurrent hospitalisation is patients’ nonadherence to self-care recommendations. Globally, medication nonadherence is a public health concern and a common phenomenon amongst patients with HF. This represents a continuous burden for patients, their relatives and the health-care system. The overall aim of this research is to develop an in-depth understanding of the issue of medication adherence among patients with HF in Nigeria by integrating the perspectives of both the patients and the healthcare providers.
Methods
Firstly, a review of empirical literature/qualitative meta-synthesis was conducted to explore the facilitators and barriers to adherence in heart failure. Secondly, a qualitative method by the means of in-depth, semi-structured interviews was utilised in exploring the perspectives of the patients, alongside their caregivers and their healthcare professionals regarding the factors they perceive are barriers and facilitators of medication adherence. The lived experience of patients living with HF was also explored. The results of which are discussed in two chapters. By the means of purposive sampling, a total of 65 participants (45 patients alongside their caregivers and 20 healthcare professionals) who met the inclusion criteria participated in this study. The interviews were recorded, transcribed verbatim and analysed by thematic content analysis.
Results The rate of medication adherence was suboptimal (33%). The main barriers identified by the patients and their healthcare professionals include financial constraints, influence of religious beliefs, and culture, patients’ attitude and behaviour towards their medications, knowledge deficit, forgetfulness, interaction with the healthcare system among others. Experiencing side effects was a barrier identified by the patients but not the healthcare professionals. The key facilitators of medication adherence identified were forming a routine, support from family and friends, health education and counselling, and insight about the condition, medications prescribed and the repercussion of medication nonadherence. The strategies to improve medication adherence were also identified.
Conclusion This study provides clear evidence that the factors influencing medication adherence are multiple and interrelated. As the barriers of medication adherence are multiple, solutions/ interventions to improve adherence should be holistic, multifaceted, and patient-centered in order to be effective.
2022-06-01T00:00:00ZPerspectives on Adolescents’ Obesity Amidst the Nutrition Transition in LebanonBou Kheir, Miriamhttp://hdl.handle.net/10034/6256142022-08-31T11:26:00Z2020-01-01T00:00:00ZPerspectives on Adolescents’ Obesity Amidst the Nutrition Transition in Lebanon
Bou Kheir, Miriam
Adolescent obesity is a major public health concern, increasingly affecting low and middle-income countries (LMICs) undergoing the nutrition transition. In developed countries, governments had the time to adjust to this rise in the consequent non-communicable diseases (NCDs), whereas the developing world is facing a triple burden of nutrition-related disease simultaneously. However, amidst the nutrition transition, drivers to obesity may differ within the same country especially
between the urban and rural areas, depending on the context and environmental factors. In order to unravel how the nutrition transition process unfolds in both urban and rural areas, an exploration of the factors affecting adolescents’ lifestyle and eating behaviours, in the current context was deemed appropriate. Additionally, exploring stakeholders’ views on adolescents’ obesity
including facilitators and barriers to obesity prevention is key in intervention and policy drawing. This study thus aimed to explore in-depth, whether, how, and to what extent is the nutrition transition currently affecting adolescents’ environments in Lebanon, focusing on both adolescents’ and stakeholders’ perspectives, awareness, and barriers to the prevention of adolescents’ obesity. The study used a sequential multi-method approach along a bricolage methodology. The first phase of the study adopted a qualitative approach, involving focus groups with adolescents (n = 78) to explore their perceptions regarding their eating behaviours as well as the role of the environment surrounding them in both urban and rural areas. A number of direct (availability of Western foods, peer pressure, parental control, eating location, body image) and indirect (adolescence autonomy, role modeling, cultural beliefs, peer surveillance) factors seemed to influence adolescents’ eating behaviours. Almost similar behaviours were perceived between the urban and rural area, showcasing the impact of the nutrition transition in both areas although different underlying factors were stated. The factors identified in this study were grouped and discussed based on the socioecological model (SEM) highlighting the importance of the social and environmental influences on adolescents’ eating behaviours. The second phase of the study adopted a qualitative approach; using one-to-one interviews to investigate stakeholders’ opinions on adolescents’ obesity. The study highlighted the barriers and facilitators in preventing adolescents’ obesity in relation to adolescents’ eating behaviours and the surrounding environment. Key stakeholders interviewed in this phase included different sectors such as the Ministry of Education, Municipalities, Transportation NGOs, with a special emphasis
on the school setting including school directors, manager of school cafeteria, sports teacher, school nurse and head teacher. Interviews revealed the lack of awareness concerning the obesity problem and the importance of the environmental influences, a lack of intersectoral cooperation between stakeholders in Lebanon and a greater emphasis on the individual responsibility in the prevention of adolescents’ obesity. This study has revealed and engaged with the varied conceptualisations of obesity causation amongst adolescents, in both urban and rural areas, amid the nutrition transition in Lebanon. Acknowledging that the causes of obesity are complex this study collects insights of both adolescents and key stakeholders’ perceptions; to date, no study has engaged with both in Lebanon, justifying the need for the present study. Clearly, in keeping with the literature on the different rate of nutrition transition between rural and urban environments further justifies the consideration of both context. Given the findings of this study in regards to the dramatic changes affecting both urban and rural areas regarding the number of meals consumed away from home, the increase in fast-food consumption and the increase in sedentary lifestyles, new challenges in relation to adolescent obesity prevention in LMICs are created. The creation of supportive local environments, in both urban and rural areas, represents an important avenue where eating behaviours concerns, and thus adolescents’ obesity can be addressed.
2020-01-01T00:00:00ZPublic Policy for Obesity Prevention in LebanonAl Kattan, Malikahttp://hdl.handle.net/10034/6253282022-08-31T11:27:30Z2020-12-01T00:00:00ZPublic Policy for Obesity Prevention in Lebanon
Al Kattan, Malika
Background: In Lebanon, the population is experiencing nutrition transition and a high prevalence of obesity. Studies have shown that the Lebanese people are shifting their dietary behaviours from the traditional Lebanese diet, a variation of the Mediterranean diet, towards a westernised diet and are being physically inactive. To achieve a population behaviour change and
address the obesity epidemic, the root causes of these behaviours and food choices should be explored and addressed. This approach requires joint efforts from different sectors such as the government, healthcare, and civil society to develop action plans and enact policies. In Lebanon, the factors that influence eating behaviours and physical activity are still not explored, national level policies are still lacking, and researchers have called for an urgent need to implement policies to halt the rise of obesity prevalence.
Aims and objectives: The general aim of this thesis is to explore the perceived factors that influence adults’ eating behaviours and physical activity using the socio-ecological model as the conceptual framework. In addition, this PhD research explores the relevant contribution and the position of different stakeholders towards obesity prevention in Lebanon. Finally, this thesis
draws on lessons learned from countries worldwide that help in developing guidelines for obesity prevention in Lebanon.
Methods: Two studies were conducted for this PhD research. In the first study, the Photovoice method was used to engage Lebanese adults from the North Governorate to explore different factors that influence their eating behaviours and physical activity and to identify their perceptions towards the actions needed to address obesity. The second study involved a series
of one-to-one face-to-face semi-structured interviews which were conducted with key stakeholders from different public and private sectors (government, civil society, education, and healthcare). These interviews aimed to explore the key stakeholders’ perceptions towards obesity and its causes, their relevant contribution towards obesity prevention, their priority of action to address obesity, and finally the barriers to effective action to reduce obesity in Lebanon.
Results: The findings of the two qualitative studies show that obesity is commonly perceived as a body image issue rather than a health issue. Some of the main factors that were perceived to influence Lebanese adults’ eating behaviours and physical activity were: females’ (wives’ and mothers’) employment, social gatherings, and social norms (e.g. food and meal sharing), safety
concerns, the availability of countless unhealthy food options that are relatively cheaper than healthy food, the lack of a physical environment that encourages physical activity, and food marketing and advertisements. The results of the stakeholder’s interviews show that the key stakeholders are aware of the nutrition transition and some of the underlying environmental
factors that caused these behaviour changes. Yet, most of the key stakeholders framed obesity in an “individualistic approach” by focusing on unhealthy dietary behaviours, the physical inactivity and placed the responsibility on individuals for their lifestyle. Due to their approach, most of them focused their actions on raising awareness such as the role of education. Some of
the barriers to effective policy action to address obesity in Lebanon are the political instability, lack of public demand for action, and lack of coordinated multi-sectoral actions.
Implications: The recognition of obesity as a disease as well as strengthening the public, stakeholders’, and policymakers’ support towards obesity prevention strategies are essential to overcome the “policy inertia” in Lebanon. The key areas that need to be addressed for obesity prevention are raising awareness on obesity health consequences, increasing access to healthy
food in public and private settings, limiting unhealthy food advertisements, and fiscal measures such as taxing unhealthy food and subsidising healthy food. To facilitate the implementation of policies that aim to prevent obesity, a systematic plan of action should be developed. To engage stakeholders from different sectors and establish a national multi-sectoral collaboration, national strategies and policies that follow a Health in all Policies Approach (HiPA) are recommended. This requires strong leadership from the government.
Conclusions: There is an urgent need to shift the actions beyond targeting the individual by implementing public policies to address the obesogenic environment in Lebanon. Recommendations for research, policy actions, and practice are provided to guide the action towards establishing an appropriate public policy that recognises the need to adopt a socioecological
model of implementation.
2020-12-01T00:00:00Z