Psychosocial and Clinical Aspects of Eating Disorder in Young Females. Khoo P.J. 1 and Ho T.F. 2

Transcription

1 Psychosocial and Clinical Aspects of Eating Disorder in Young Females ABSTRACT Khoo P.J. 1 and Ho T.F. 2 Department of Physiology, Faculty of Medicine, National University of Singapore 10 Kent Ridge Road, Singapore Eating Disorder (ED) is a health problem which involves abnormal behavior in diet and in maintaining one s weight. The three main types of eating disorder that we looked into in this study are Anorexia Nervosa (AN), Bulimia Nervosa(BN) and Binge Eating Disorder. Individuals with AN cannot maintain a body weight that is expectable for their age and height. Individuals with the Restricting Type AN restrict their food intake and undergo compulsive exercises. Patients of the Binge Eating/Purging Type not only restrict their diet but also engage in binge eating and / or purging behaviors which include self-induced vomiting, abusing of laxatives, diuretics or enemas. Individuals with Bulimia Nervosa engage themselves regularly in discrete periods of overeating. These are then followed by inappropriate compensatory behavior in order to prevent weight gain, such as purging and excessive exercise. Another type of ED that we want to look into is Binge Eating. This is characterized by uncontrolled recurrent periods of overeating. However, these people with binge eating disorder usually do not purge. STUDY (PART I) INTRODUCTION Patients with clinical manifestation of ED undergo several physiopathological changes in their bodies. Physical signs and symptoms include changes in cardiovascular system, changes in endocrine balance, changes in gastrointestinal functions and other problems in kidney, pancreas, dental etc. In the study we emphasized on the cardiovascular changes and the hormonal imbalance that manifest in individuals with ED. A study was carried out from May to September of 2002 by Lim Y.H (a research partner) and myself. The study evaluates the correlations between the severity of ED and various cardiovascular variables including heart rate, blood pressure, standard ECG and signal average ECG parameters. The main subjects of the research were outpatients with known clinical manifestation of eating disorder who attended Child Guidance Clinic at Health Promotion Board or Eating Disorders Clinic at Institute of Mental Health (IMH). 1 Student, Biomedical Science year 3 2 Associate Professor, Department of Physiology, Faculty of Medicine, National University of Singapore

2 METHOD In the study, anthropometric measurements of height, weight, blood pressure, mid-arm circumference, skinfold measurements (triceps skinfold and subscapular skinfold) were done. Standard 12-lead ECG and also Signal Average ECG (SAECG) were measured for each subject. Three SAECG recordings are of interest for this study, they are Total QRS duration (TQRS), duration of HFLA signals less than 40µV (HFLA), and the RMS Voltage in terminal 40ms of the QRS. RESULTS AND DISCUSSION Girls with restricting type Eating disorder have significantly lower heart rate, lower diastolic blood pressure, abnormally prolonged TQRS (117.7ms) and HFLA( 57.6ms). For Binge-Purge Type ED patients, cardiovascular variables are similar to that of the normal healthy females. Therefore individuals with Restricting Type ED have higher risk of suffering from cardiac abnormalities. Apart from cardiovascular changes, patients also had endocrine imbalance leading to amenorrhea for more than three consecutive menstrual cycles. It had been hypothesized that there is increased incidence of amenorrhea in Anorexia Nervosa patients than in Bulimia Nervosa patients. Our results show that individuals with AN have significantly higher incidence of amenorrhea. The symptoms can then serve as a warning signs for young females who exhibit abnormal eating patterns to look for professional consultation and treatments. In this study the psychosocial aspects of the ED were also evaluated by using a comprehensive questionnaire to assess the epidemiology of clinical Eating Disorder patients. Results showed that patients come from families with better financial resources compared to the controls. Most of the patients perform well in school and at work. It was also found that more of ED patients have poorer relationships with their parents and friends than healthy females. However, the study was only done on 23 patients and 23 healthy controls, the small sample size may be a factor to biasness and inaccuracy in analysis. It is recognized that ED is difficult and time-consuming to treat. Many patients have been followed up for years with slow progress. It is therefore highly worthwhile to consider preventive and early detection measures so that the cost of treatment and morbidity of the disease can be minimized. Thus in the next part, I will highlight the planning of a large population study designed to evaluate the predisposing factors or risk factors that can lead to eating disorders. STUDY (PART II) INTRODUCTION The objective of this part of the study is to evaluate the contributing factors in terms of psychosocial aspects and eating patterns in order to assess the epidemiology of sub-clinical ED in young females in Singapore. The study is designed to document the prevalence of the symptoms of

3 ED among these subjects and to find out how early this problem manifests in adolescents. This study is a large population study involving close to 8000 participants for phase 1 screening. The study has just commenced after a lengthy preparation phase in which I was involved. METHOD The main issues considered during the planning phase are as follows: Population We target to sample 8000 individuals from the female population with age from 12 to 24 in Singapore. The subjects should be representative of the population studied. This then highlights the importance of the sampling method. Sampling method Appropriate sampling method helps to eliminate the bias in the screening. Young females are randomly selected from secondary schools, polytechnics and National University of Singapore. The choice of secondary schools is generated by computerized randomization. From the full list of female students provided a random sample is then computer generated. One advantages of sampling in schools is that samples are conveniently located at one place. Randomization is essentially important to eliminate selection bias and non response bias. It provides every person in the list with equal chances of being selected as random samples. Questionnaires In this Health and Nutritional Assessment survey, the Eating Disorder Inventory (EDI) questionnaire and Eating Attitudes Test (EAT) are used as screening instruments in the first stage to determine factors likely to influence attitudes and behavior towards eating disorder. EDI and EAT have been validated and made culturally suitable. These two screening questionnaires are used to screen for individuals who have the characteristics of or at higher risk of ED. A comprehensive questionnaire is also included to evaluate the psychosocial aspects and to assess the epidemiology of sub clinical ED. Participants are required to complete a food diary by recording down the amount and type of food that is consumed for two weekdays and one weekend. It is useful in the evaluation of the dietary profile of subjects by nutritionists. Subjects who fulfill one or more of the following will be subjected to a diagnostic questionnaire namely Eating Disorder Examination (EDE). a) Scores beyond the EDI norm ranges b) A score of at least 26 on the EAT c) Weight at or below the 3 rd percentile for age d) BMI of 17 or less These selected subjects will then undergo clinical examinations to determine various physiological parameters. In this study, the main purpose of EDI and EAT is to distinguish the two groups of subjects, those at a higher risk or with increased tendency of ED, and those who are normal healthy

4 individuals, who will then serve as a control group. Subjects with higher risk are then evaluated further to determine the predisposing factors or risk factors for eating disorders e.g. family factors, educational level, age group, social and psychological factors and personal attitude towards body image and dietary practice. With the contributing factors identified, early detection of ED can then be possible by recognizing the warning signs and cultural backgrounds that render the individual more inclined to the problem. RESULTS AND DISCUSSION The screening questionnaires EDI and EAT are assessed by psychiatrists and psychologists. The data of the screening will eventually be analyzed using statistical methods such as multi-regression analysis, multivariate analysis of variants (MANOVA) by the statisticians to find out the association of subjects demographic information with the severity of ED. We hope that by identifying the predisposing factors which indirectly leads to the occurrence of ED, we can increase the social awareness of this psychiatric problem via health education and thus provide treatments as early as possible. Even though samples are selected from random schools, there is still limitation in the sampling method. We are unable to locate the young females who dropped out of local schools or those who start working after completing primary education. However, these minorities are of high potential and interest in research because they have distinctively different social and cultural backgrounds from school students and may show different prevalence in the symptoms of ED. On the other hand, in the screening in schools, the number of subjects available is dependent on the schools that are willing to participate in the study. We aim to reach the target number of participants yet we also understand the reservations held by schools that may limit the number of subjects achieved. The food diary that is attached in the Health and Nutritional Assessment can introduce recall bias when it is inevitable for subjects to recall the accurate amount of food that they have consumed in the past weekend instead of recording them as they eat. The response rate of the survey can potentially ruin the otherwise well-designed research study. Some members of the sample simply refuse to respond. Others have the best of intention, but may not find the time to send in the questionnaires by the due date, or misplace the instrument. The only limitation is the lack of incentive to motivate and boost the rate of response. Resolution such as phone calls reminder and post back service can be effective in minimizing the drop out rate. The implication of incentives will be proposed to increase the responsiveness from the samples when necessary. REFERENCE Risto Lehtonen and Erkki J. Pahkinen, Practical Methods for Design and Analysis of Complex Surveys, Pg

5

6