Markers of Nutritional Assessment in Children with Gastrointestinal Illnesses BREKHNA AURANGZEB A THESIS SUBMITTED FOR THE DEGREE OF MASTERS OF SCIENCE (PAEDIATRICS) SCHOOL OF WOMEN’S AND CHILDREN’S HEALTH UNIVERSITY OF NEW SOUTH WALES DECEMBER 2008 i Certificate of originality I hereby declare that this submission is my own work and to the best of my knowledge it contains no materials previously published or written by another person, or substantial proportions of material which have been accepted for the award of any other degree or diploma at UNSW or any other educational institution, except where due acknowledgment is made in the thesis. Any contribution made to the research by others, with whom I have worked at UNSW or elsewhere, is explicitly acknowledged in the thesis. I also declare that the intellectual content of this thesis is the product of my own work, except to the extent that assistance from others in the project’s design and conception or in style, presentation and linguistic expression is acknowledged. ________________________ Signature ii Table of Contents Table of Contents -----------------------------------------------------------------------------iii List of Tables---------------------------------------------------------------------------------- vii List of Figures---------------------------------------------------------------------------------- ix Abstract ----------------------------------------------------------------------------------------- xi Acknowledgments-------------------------------------------------------------------------- xiii Abbreviations-------------------------------------------------------------------------------- xiv Chapter 1 Introduction-------------------------------------------------------------------1 1.1 Malnutrition ----------------------------------------------------------------------------1 1.1.1 Under-nutrition ---------------------------------------------------------------------1 1.1.2 Obesity--------------------------------------------------------------------------------3 1.1.3 Epidemiology of malnutrition----------------------------------------------------4 1.2 Relationship between disease and malnutrition--------------------------------5 1.3 Epidemiology of malnutrition in hospitalised children------------------------8 1.4 Importance of early detection of malnutrition ----------------------------------9 1.5 Research rationale------------------------------------------------------------------- 10 1.6 Broad aims of the research -------------------------------------------------------- 11 1.7 Specific aims -------------------------------------------------------------------------- 11 Chapter 2 Literature Review---------------------------------------------------------- 13 2.1 Full nutritional assessment-------------------------------------------------------- 13 2.1.1 Nutritional risk screening------------------------------------------------------- 13 2.1.2 Nutritional assessment---------------------------------------------------------- 29 2.2 Body Compartments ---------------------------------------------------------------- 40 2.3 Bioelectrical Impedance Analysis ------------------------------------------------ 41 2.3.1 How does BIA work?------------------------------------------------------------- 41 2.3.2 What and how does BIA measure?-------------------------------------------- 42 2.3.3 BIA Equations used in the current study ------------------------------------ 43 2.3.4 BIA advantages-------------------------------------------------------------------- 45 2.3.5 Methods of BIA -------------------------------------------------------------------- 48 2.3.6 Comparison with other techniques ------------------------------------------- 49 2.3.7 Limitations of BIA ---------------------------------------------------------------- 50 2.4 Biochemical marker of fat cells - Leptin ---------------------------------------- 51 2.4.1 Physiology of Leptin ------------------------------------------------------------- 51 2.4.2 Factors that influence leptin levels ------------------------------------------- 54 2.4.3 Nutritional status and leptin --------------------------------------------------- 56 2.4.4 Disease and leptin ---------------------------------------------------------------- 57 2.4.5 Summary of leptin in nutritional assessment ------------------------------ 58 2.5 Rationale of different methods of nutritional assessment in current research----------------------------------------------------------------------------------------- 58 2.6 Coeliac disease ----------------------------------------------------------------------- 60 2.6.1 Prevalence ------------------------------------------------------------------------- 60 2.6.2 Pathophysiology ------------------------------------------------------------------ 60 iii 2.6.3 Presentation ----------------------------------------------------------------------- 60 2.6.4 Nutritional status of children with coeliac disease ------------------------ 61 2.6.6 Serum leptin level in coeliac disease ----------------------------------------- 63 2.6.7 Nutritional assessment in long term management of children with coeliac disease------------------------------------------------------------------------------ 64 2.6.8 Importance of thorough nutritional assessment in coeliac disease---- 65 2.7 Inflammatory Bowel Disease------------------------------------------------------ 67 2.7.1 Incidence --------------------------------------------------------------------------- 67 2.7.2 Aetiology and pathogenesis ---------------------------------------------------- 67 2.7.3 Presenting features -------------------------------------------------------------- 68 2.7.4 Nutritional status of IBD children--------------------------------------------- 68 2.7.5 Leptin in IBD----------------------------------------------------------------------- 72 2.7.6 Importance of nutritional assessment in children with IBD------------- 73 Chapter 3 General Methods ----------------------------------------------------------- 75 3.1 Study design and enrolment procedures for Study 2 and 3 ---------------- 75 3.1.1 Inclusion criteria------------------------------------------------------------------ 75 3.1.2 Exclusion criteria ----------------------------------------------------------------- 76 3.2 Study groups-------------------------------------------------------------------------- 76 3.2.1 Definitions ---------------------------------------------------------------------- 76 3.3 Sample size---------------------------------------------------------------------------- 77 3.4 Details of the selected study population---------------------------------------- 77 3.4.1 Reasons for selection of the controls ----------------------------------------- 79 3.5 Anthropometric measurements -------------------------------------------------- 80 3.5.1 Measurement of weight --------------------------------------------------------- 80 3.5.2 Measurement of height---------------------------------------------------------- 81 3.5.2 Measurement of mid upper arm circumference (MUAC) ---------------- 83 3.5.3 Measurement of triceps skin fold thickness (TSF) ------------------------ 84 3.6 Bioelectrical impedance analysis------------------------------------------------- 86 3.7 Serum leptin analysis --------------------------------------------------------------- 87 3.7.1 Collection and storage of blood samples ------------------------------------ 87 3.7.2 Analysis of blood samples ------------------------------------------------------ 88 3.7.3 General ELISA protocol---------------------------------------------------------- 88 Chapter 4 Prevalence of Malnutrition and Risk of Under-nutrition in Hospitalised Children ---------------------------------------------------------------------- 90 4.1 Introduction -------------------------------------------------------------------------- 90 4.1.1 Study aims-------------------------------------------------------------------------- 92 4.2 Methodology-------------------------------------------------------------------------- 92 4.2.1 Study design ----------------------------------------------------------------------- 92 4.2.2 Study population------------------------------------------------------------------ 92 4.2.4 Training of interviewers -------------------------------------------------------- 93 4.2.5 Interviewers ----------------------------------------------------------------------- 93 4.2.6 Methods ---------------------------------------------------------------------------- 93 4.2.7 Management of anthropometric data ---------------------------------------- 95 4.3 Results --------------------------------------------------------------------------------- 96 4.3.1 Study population------------------------------------------------------------------ 96 4.3.2 Anthropometric data------------------------------------------------------------- 96 4.3.3 NRS Scores ------------------------------------------------------------------------- 99 4.4 Discussion--------------------------------------------------------------------------- 104 iv 4.4.1 Prevalence of over nutrition at SCH compared with other studies -- 104 4.4.2 Socio-demographic features of obese children--------------------------- 105 4.4.3 Prevalence of under-nutrition at SCH compared with other studies 106 4.4.4 Prevalence of nutritional risk in this study ------------------------------- 107 4.4.5 Comparison between low risk and high nutritional risk groups ----- 107 4.4.6 Prevalence of NRS as compared to other studies ------------------------