AN EPIDEMIOLOGICAL STUDY OF ADOLESCENT PSYCHOPATHOLOGY AND GILLES DE LA TOURETTE SYNDROME IN WEST ESSEX Heatha Amanda Karen Hornsey Thesis submitted for the degree of Doctor of Philosophy to the Faculty of Clinical Science, University of London Department of Psychiatry and Behavioural Sciences University Coiiege London 2003 ProQuest Number: U644013 All rights reserved INFORMATION TO ALL USERS The quality of this reproduction is dependent upon the quality of the copy submitted. In the unlikely event that the author did not send a complete manuscript and there are missing pages, these will be noted. Also, if material had to be removed, a note will indicate the deletion. uest. ProQuest U644013 Published by ProQuest LLC(2016). Copyright of the Dissertation is held by the Author. All rights reserved. This work is protected against unauthorized copying under Title 17, United States Code. Microform Edition © ProQuest LLC. ProQuest LLC 789 East Eisenhower Parkway P.O. Box 1346 Ann Arbor, Ml 48106-1346 Abstract ABSTRACT The principal aims of this study were threefold. Firstly, the study set out to estimate the prevalence of mental health problems in a population of 13-14 year old adolescents attending mainstream secondary schools in West Essex. Using a cross-sectional methodology, standardised screening questionnaires were used to identify the presence of specific disorders, based on information from parents, teachers and adolescents. Comparisons were made between those who were and were not referred for treatment. Secondly, a three-stage ascertainment procedure was embedded in the study methodology to determine the prevalence of Gilles de la Tourette Syndrome (TS) in the same population. This combined the use of screening questionnaires with semi-structured interviews, followed by a systematic assessment by an expert clinician in the field of TS for verification and diagnosis. Thirdly, a longitudinal component of the study was designed to measure academic attainment, using General Certificates of Secondary Education (GCSEs), two years later. An overall prevalence rate of 17.1% for psychiatric disorder was reported. This rate was higher than other study findings in nonmetropolitan areas but comparable to inner city levels, within the UK. Rates for specific disorders were variable. Only 34% of those with positive psychopathology were referred to clinics, suggesting a large percentage of unmet need. The prevalence of TS ranged between 0.76% and 1.85%, which is higher than earlier studies but in line with recent ones. Symptoms were milder than those identified in clinics, but comorbidity was high. None of those attending clinics had been referred for their TS symptomatology. Page 2 Abstract Externalising behaviours were significantly associated with poor GCSE outcome, and path analysis models identified that negative outcomes were best predicted by Conduct Disorder once the number of GCSEs entered for were taken into account. Teachers were found to be good at predicting GCSE passes overall. Page 3 Acknowledgements ACKNOWLEDGEMENTS There are a number of people to whom I would like to express my sincerest thanks and appreciation, enabling me to complete this thesis. Professor Mary Robertson and Professor Harry Zeitlin for their supervision and continued encouragement, support and patience throughout the entire project. I would also like to extend my thanks to their respective families. Professor Robert Goodman for his advice during the project on the use of his questionnaire, and his encouragement. My friend and colleague, Ms Caiomhe O’Sullivan, for her advice on statistical analysis. Professor Chris McManus for his time in teaching me about multivariate analysis and, especially, for his enthusiasm for the project. Dr Eric Brunner for enabling me to attend his lectures on epidemiology at UGL. All the headteachers, staff, pupils and their families from West Essex who participated in this study and made it possible. I would also like to thank my parents, family and friends who have encouraged me throughout this long project, and for their patience. I would especially like to thank my mother for her help in cross checking references. My deepest thanks for funding most of this project goes to the Child Mental Health Research Trust (C-Ment), whose trustees have been especially supportive. Additional funding was provided by The American Tourette Syndrome Association and North East Essex Mental Health NHS Trust. Page 4 Statement STATEMENT The collection, collation and analysis of the data presented in this thesis were carried out by the author herself, with the following exceptions. Professor Mary Robertson conducted clinical interviews with the young people identified in the sample by the author, as either TS probable or TS definite. Professor Robertson provided the definitive TS diagnosis. Professor Harry Zeitlin provided the clinical diagnosis on the young people referred to the participating child and family clinics, based on a thorough assessment of the case notes, where a diagnosis had not been provided. Support for statistical analysis was provided by Professor Chris McManus (University College London), Dr Sube Banerjee (Institute of Psychiatry) and Ms Caoimhe O’Sullivan (R&D Directorate, University College London Hospitals). Page 5 Contents CONTENTS Page Number ABSTRACT 2-3 ACKNOWLEDGEMENTS 4 STATEMENT 5 CONTENTS 6-18 GLOSSARY OF TERMS 19-21 REFERENCES 326-377 APPENDICES 378-407 TABLES 408-436 FIGURES 437-464 CHAPTER 1 PROLOGUE 22-29 CHAPTER 2 ADOLESCENT PSYCHOPATHOLOGY, REFERRAL PATTERNS, PSYCHOSOCIAL RISK FACTORS AND 30-191 EDUCATIONAL PERFORMANCE 2.1 Introduction to the Literature Review 30-33 2.2 PREVALENCE OF ADOLESCENT PSYCHOPATHOLOGY IN SCHOOL BASED POPULATIONS 2.2A Hyperactivity 34-57 2.2.1.1 Introduction 34 2.2.1.2 Issues in classification and diagnosis 35 2.2.1.3 Phenomenology 39 2.2.1.4 Gender differences 42 2.2.1.5 Informant reliability and rating scales 45 2.2.1.6 Continuities into adulthood 48 2.2.1.7 Prevalence in community studies 51 2.2.1.8 Summary 56 2.2.2 Conduct Disorder 58-75 2.2.2.1 Introduction 58 2.2.2.2 Classification and diagnosis 59 2.2.2.S Phenomenology 62 Page 6 Contents 2.2.2A Developmental continuities and discontinuities of disorder 65 2.2.2.S Educational and Adult outcomes 69 2.2.2.G Gender differences 71 2.2.27 Prevalence in the community 73 2.2.2.8 Summary 74 2.2.3 Depression 76-96 2.2.3.1 Introduction 76 2.2.5.2 Classification, Diagnosis and Phenomenology 77 2.2.3.3 Gender differences 81 2.2.3.4 Comorbidity 84 2.2.3.5 Depressive continuities and adult outcomes 86 2.2.3.6 Rating scales and informant reliability 88 2.2.3.7 Prevalence in community studies 91 2.2.3.5 Summary 95 2.2.4 Gilles de la Tourette Syndrome (TS) 97-133 2.2.4.1 Introduction 97 2.2.4.2 History 97 2.2.4.5 Diagnosis and assessment 103 2.2.4.4 Aetiology and characteristics 107 - symptom manifestation 108 - associated features 108 - age of onset 108 - symptom course 110 - sex ratios 111 - premonitory sensations 111 - comorbidity 112 - cross cultural characteristics 112 2.2.4.5 Genetics 113 2.2.4.G Comorbidity of TS 116 2.2.4.7 Prevalence of tics 119 2.2.4.5 Prevalence in mainstream education 121 Page 7 Contents 2.2A.9 Summary 132 2.3 RISK FACTORS FOR PSYCHOPATHOLOGY IN 134-141 ADOLESCENCE 2.3.1 Introduction 134 2.3.2 Risk factors for individual disorders 135 2.3.3 Summary 140 2.4 REFERRAL TO SERVICES 142-153 2.4.1 Introduction 142 2.4.2 Service provision and access to services 143 2.4.3 Issues of caseness 145 2.4.4 Differences between referred and 148 nonreferred groups 2.4.5 Prevalence of disorder in clinic samples 150 2.4.6 Summary 152 2.5 PSYCHOPATHOLOGY AS A RISK FACTOR FOR EDUCATIONAL PERFORMANCE 154-186 2.5.1 Introduction 154 2.5.2 Terminology 155 2.5.3 Association between externalising behaviours and educational performance 156 2.5.4 Co-morbid behaviour and learning difficulties and their influence on educational 152 performance 2.5.5 Comorbidity of externalising behaviours and different outcomes 157 2.5.6 Causal direction 171 2.5.7 The effects of continuities of behaviour and poor educational performance into 176 adulthood 2.5.8 Efficacy of treatment for behaviour to improve educational performance 179 2.5.9 Summary 184 Page 8 Contents 2.6 CONCLUSIONS AND STATEMENT OF HYPOTHESES 187-191 CHAPTER 3 METHODOLOGY 192-235 3.1 Rationale for the study 192 3.2 West Essex Pilot Study 195 3.3 The sample 199 3.4 Behaviour Screening Questionnaires 200 3.4.1 Birleson Depression Self-Rating Scale 200 3.4.2 Conners Abbreviated Parent Questionnaire 205 3.4.3 Strengths & Difficulties Questionnaire 208 3.4.4 Apter four tic screening questionnaire 213 3.4.5 National Hospital Interview Schedule for the assessment of Gilles de la Tourette 214 Syndrome (TS) (brief version) 3.4.6 Yale Global Tic Severity Scale 216 3.4.7 Diagnostic Confidence Index 219 3.5 Procedure 221 3.5.1 Mainstream Schools 221 3.5.1.1 Stage One - initial data collection 222 - Parent data - Teacher data - Young person data 3.5.1.2 Stage Two - telephone follow-up interviews for TS 226 3.5.1.3 Stage Three - identification of TS 227 3.5.1.4 Stage Four - education performance data collection 229 3.6 Data Quality 230 3.7 Nonresponse rates 231 3.8 Referral information 232 3.9 Teacher ratings and GCSE examinations 233 3.10 Statistical Methods 234 Page 9 Contents CHAPTER 4 RESULTS1 : PREVALENCE OF EMOTIONAL AND BEHAVIOURAL PSYCHOPATHOLOGY 236-251 4.1 Introduction 236 4.2 Sample characteristics 237 4.3 Missing data 238 4.4 Prevalence of mental health symptomatology 239 4.5 Associations