Can J Diabetes 37 (2013) 408e414
Contents lists available at ScienceDirect
Canadian Journal of Diabetes journal homepage: www.canadianjournalofdiabetes.com
Original Research
Psychological Correlates of Eating Disorder Symptoms and Body Image in Adolescents with Type 1 Diabetes Laura A. Kaminsky PhD a, b, *, Deborah Dewey PhD c, d, e a
Department of Paediatrics, University of Calgary, Calgary, Alberta, Canada Diabetes Clinic, Alberta Children’s Hospital, Calgary, Alberta, Canada Departments of Paediatrics and Community Health Sciences, University of Calgary, Calgary, Alberta, Canada d Behavioural Research Unit, Alberta Children’s Hospital, Calgary, Alberta, Canada e Alberta Children’s Hospital Research Institute for Child and Maternal Health, Alberta, Canada b c
a r t i c l e i n f o
a b s t r a c t
Article history: Received 1 March 2013 Received in revised form 24 June 2013 Accepted 28 June 2013
Objective: To examine eating disorder symptoms and body image in adolescents with type 1 diabetes and to investigate the associations among social support, self-esteem, health locus of control, eating disorder symptoms and body image. Methods: Forty-six adolescents with type 1 diabetes and 27 healthy comparison adolescents completed questionnaires. Results: No significant differences were identified in eating disorder symptoms and body image between adolescents with type 1 diabetes and healthy comparison adolescents. Regression analyses were completed with the full sample of adolescents with type 1 diabetes and healthy comparison adolescents. Higher levels of social support and being male were associated with a more positive body image, less body dissatisfaction and a lower drive for thinness. A belief by the adolescents that parents or healthcare providers (i.e. external powerful others locus of control) were in control of their health was associated with a more positive body image and less body dissatisfaction. Higher self-esteem was associated with a greater drive for thinness and a higher level of body dissatisfaction. Conclusions: Social support, health locus of control and self-esteem appear to be important correlates of eating disorder symptoms and body image in adolescents with diabetes and their typically developing peers. Ó 2013 Canadian Diabetes Association
Keywords: adolescents body image eating disorders type 1 diabetes
r é s u m é Mots clés : adolescents image corporelle troubles du comportement alimentaire diabète de type 1
Objectif : Examiner les symptômes du trouble de comportement alimentaire et l’image corporelle chez les adolescents ayant le diabète de type 1 et explorer les liens entre le soutien social, l’estime de soi, le locus de contrôle de la santé, et les symptômes du trouble du comportement alimentaire et l’image corporelle. Méthodes : Quarante-six (46) adolescents ayant le diabète de type 1 et 27 adolescents témoins en santé ont rempli les questionnaires. Résultats : Aucune différence significative n’a été observée dans les symptômes du trouble du comportement alimentaire et l’image corporelle entre les adolescents ayant le diabète de type 1 et les adolescents témoins en santé. Les analyses de régression ont été effectuées à partir de l’échantillon complet des adolescents ayant le diabète de type 1 et des adolescents témoins en santé. Les niveaux plus élevés de soutien social et du fait d’être de sexe masculin ont été associés à une image corporelle plus positive, à moins d’insatisfaction corporelle et à une plus faible volonté de mincir. Le fait pour les adolescents de croire que les parents ou les prestataires de soins (c.-à-d. d’autres locus de contrôle externes forts) prenaient en charge leur santé a été associé à une image corporelle plus positive et à moins d’insatisfaction corporelle. Une plus grande estime de soi a été associée à une plus grande volonté de mincir et à un niveau plus élevé d’insatisfaction corporelle. Conclusions : Le soutien social, le locus de contrôle de la santé et l’estime de soi semblent être d’importants corrélats des symptômes du trouble du comportement alimentaire et de l’image corporelle chez les adolescents et leurs pairs ayant un développement normal. Ó 2013 Canadian Diabetes Association
* Address for correspondence: Laura A. Kaminsky, PhD, Diabetes Clinic, Alberta Children’s Hospital, 2888 Shaganappi Trail NW, Calgary, Alberta T2T 5C7, Canada. E-mail address: [email protected]. 1499-2671/$ e see front matter Ó 2013 Canadian Diabetes Association http://dx.doi.org/10.1016/j.jcjd.2013.06.011
L.A. Kaminsky, D. Dewey / Can J Diabetes 37 (2013) 408e414
Introduction Type 1 diabetes is a common chronic illness of childhood (1). It is managed by a complex treatment regimen that aims at maintaining good glycemic control to reduce the risk of short- and long-term medical complications. Adolescence is a particularly challenging time for maintaining optimal glycemic control as a result of physiological changes and a decrease in diabetes treatment adherence secondary to various psychosocial factors (2). Intensified treatment protocols for type 1 diabetes have been found to result in weight gain, which may be distressing to adolescents. To control weight, some adolescents with diabetes omit insulin or engage in disordered eating behaviours, such as reducing caloric intake or binge eating (3). Studies focusing exclusively on adolescent girls found that 10% to 14% reported deliberate insulin omission as a weight control practice (4e6). Additional factors that may contribute to the development of disordered eating in adolescents with type 1 diabetes are the dietary focus and dietary restraints required by the treatment regimen (7), pubertal changes (8) and internalization of media messages that express a cultural ideal of thinness (9). The prevalence of eating disorders in adolescents with type 1 diabetes ranges from 14% to 27% (5,10,11). In contrast, the rates of specific eating disorders in healthy adolescent females are 0.3% for anorexia nervosa, 1% for bulimia nervosa and 2.4% for an eating disorder not otherwise specified (12). Adolescent girls with type 1 diabetes have been reported to be at higher risk of developing eating disorders than healthy adolescent females (10,13); however, this has not been supported consistently in the research literature (11,14). Adolescents with type 1 diabetes who develop eating disorders are at high risk for developing both acute and long-term complications of diabetes including retinopathy and nephropathy (10,15e17). Thus, eating disorders can play a significant role in the diabetes health outcomes of adolescents. Body image is defined as an individual’s perspective and feelings about their body (18). Much of the research on body image has examined body dissatisfaction, that is, having a negative body image typically associated with a desire to be thinner (18). Body dissatisfaction is more common in adolescents with chronic illnesses than in healthy adolescents, and distortions in body image, body dissatisfaction and preoccupation with body weight have been linked to eating disorders (i.e. anorexia nervosa, bulimia nervosa) and milder eating disturbances (i.e. eating disorder not otherwise specified, subclinical eating disorders) (18). Recent reviews have linked deficits in self-concept and lower self-esteem, which often are used interchangeably, to an increased vulnerability to eating disturbances (8,19,20). There is limited research, however, on whether these and other factors such as social support and locus of control are protective against eating disturbances and body image distortions. Maharaj et al (17) found that self-concept deficits, maternal disordered eating or maternal weight control behaviours and impaired mother-daughter relationships were significant predictors of eating disorders in adolescent girls with type 1 diabetes. Olmsted et al (21) reported that lower self-esteem related to physical appearance, lower overall self-esteem, depression, and weight and shape concerns were more common among 9to 13-year-old girls with type 1 diabetes who developed disordered eating over a 5-year period. However, social acceptance from peers was not associated significantly with disordered eating. Gerner and Wilson (22) found that in girls without any chronic health conditions, lower peer acceptance, perceived social support from friends and friendship intimacy were associated with body image concerns. These findings suggest that self-esteem and social support could be important factors in facilitating a healthy adjustment in adolescents with type 1 diabetes. To date, no studies have examined whether locus of control and overall social support (i.e.
409
support from parents, teachers and peers) are associated with eating disorders and body image in adolescents with type 1 diabetes; however, a review of the literature suggested that these correlates are worthy of study (23). The main purpose of the present study was to investigate eating disorder symptoms and body image in adolescents with type 1 diabetes. It was hypothesized that adolescents with type 1 diabetes would report significantly more symptoms of eating disorders and a less positive body image compared with adolescents without health problems. It also was hypothesized that higher self-esteem and social support, and an internal locus of control (an individual’s belief that they have the ability to control and impact their health) (24) would be associated with fewer body image concerns and fewer symptoms of eating disorders. A cross-sectional descriptive study using adolescents’ self-reports on questionnaires was used to examine the hypotheses. This study adds to the literature because it investigates protective factors that may be associated with eating disorder symptoms and body image in adolescents with type 1 diabetes. Methods Participants Adolescents, 12 to 18 years of age, were recruited from a pediatric hospital diabetes clinic. The clinic population is 49.8% female and 50.2% male. All participants had been diagnosed with diabetes for at least 6 months. Approximately 90% of the clinic population is Caucasian and 10% are from other ethnic backgrounds. Three hundred adolescents with diabetes were selected randomly from the clinic database and were approached as potential participants. Twenty-seven adolescent girls and 19 adolescent boys (mean age, 15 years; standard deviation, 1.62) volunteered to participate in the study. Adolescents from the orthopedics clinic were chosen as a comparison sample because they were treated in the same hospital setting as the patient with diabetes but not for a chronic health condition. Four hundred potential comparison participants from the orthopedics clinic were contacted. Twenty-seven adolescents, 13 girls and 14 boys, between 12 and 18 years of age (mean age, 14.9 years; standard deviation, 1.64) volunteered to participate. These adolescents had been seen for bone fractures and were no longer active patients. There were no limitations on their physical activity or ambulation at the time of their participation. Most comparison participants did not have chronic health conditions; however, 2 had asthma and 1 had a chronic orthopedic condition. The study was approved by the University of Calgary Conjoint Health Research Ethics Board. Procedures Consent/assent forms and questionnaires were mailed to the families. Questionnaires were mailed to potential participants from the diabetes and orthepedic clinic. Two weeks after the initial questionnaire package was sent, a reminder telephone call was made to all families asking them to return the questionnaires. No compensation was offered to participants. Parents provided informed consent; adolescents completed the assent form and the questionnaires independently. The Eating Disorders Inventory-II, Body Esteem Scale for Adolescents and Adults, Social Support Scale for Children, Self-Perception Profile for Adolescents, Multidimensional Health Locus of Control Scale and Pubertal Development Scale were completed by the adolescents. Parents completed a demographics questionnaire. The questionnaires were returned to the investigators in a stamped return envelope. Families were invited to contact the principal investigator if they had any concerns or questions about the study.
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L.A. Kaminsky, D. Dewey / Can J Diabetes 37 (2013) 408e414
Measures Primary outcomes The Eating Disorder Inventory-III (EDI-III) contains 91 items that assess attitudes and behaviours associated with eating disorders and questions about height and weight, which was used to calculate body mass index (25). The EDI-III is composed of 3 Eating Disorder Risk Scales (i.e. Body Dissatisfaction, Drive for Thinness and Bulimia). Participants rate their level of agreement with test items on a 6-point Likert scale (ranging from “always” to “never”). The EDI-III is a reliable and valid measure of eating disorder symptoms and body attitudes. Internal consistencies in the present study for the 3 subscales were as follows: 0.76 for the Body Dissatisfaction scale, 0.71 for the Drive for Thinness scale and 0.79 for the Bulimia scale. The Body Esteem Scale for Adolescents and Adults (BESAA) was used to assess body image (26). It includes 23 statements. Individuals rate how often they agree with each statement on a 5point Likert scale ranging from never (0) to strongly agree (4). The questionnaire is divided into 3 main categories: body esteem (BE) regarding appearance (e.g. “I feel ashamed of how I look”), BE regarding weight (e.g. “I really like what I weigh”) and BE regarding attribution (e.g. “Other people consider me good looking”). Factor analysis has shown 3 factors that correspond to these 3 categories (24). The BESAA total score was used for the purposes of this study. High internal consistency was found for each category with Cronbach alpha reliability coefficients of 0.92 for BE regarding appearance, 0.94 for BE regarding weight and 0.81 for BE regarding attribution. Test-retest reliabilities for the categories were high (BE regarding appearance: r ¼ 0.89, BE regarding weight: r ¼ 0.92, and BE regarding attribution: r ¼ 0.83 and convergent validity was established by comparing participants’ results on this measure with their results on 2 general measures of self-esteem, the Rosenberg Self-Esteem Scale and the Global Self-Worth subscale of the SelfPerception Profile for College Students (24). Alpha reliability for the BESAA total score was 0.78 in this study. Correlates of eating disorders symptoms and body image The Social Support Scale for Children, a 24-item self-report scale, assesses children’s and adolescents’ perceptions of support from their parents, teachers, classmates and a close friend (27). Six items are used to measure each of these 4 sources of support. Children are asked to choose which of 2 opposing statements are true for them and then to identify whether the statement is “sort of true” or “really true.” Higher scores indicate greater social support. The overall score on this measure of social support was used in the present study. Children’s overall scores have been found to correlate moderately with children’s reports of self-worth. Alpha reliability for the overall social support scale in this study was 0.75. The Self-Perception Profile for Adolescents is a 45-item selfreport scale that assesses an adolescents’ sense of self-esteem (28). It includes an overall self-esteem scale, Global Self-Worth, which was used in the present study. Adolescents were asked to choose which of 2 opposing statements are true for them and then to identify whether the statement was “sort of true” or “really true.” Harter (28) reported that the measure has good validity and reliability. The alpha reliability for the Global Self-Worth scale in the present study was 0.78. The Multidimensional Health Locus of Control, Form A (29,30) consists of 18 questions about individuals’ perceptions of their control over their health. Individuals responded on a 6-point Likert scale ranging from (“strongly disagree” to “strongly agree”). Three 6-item subscales are contained in the measure (internality; e.g. “I am in control of my health”), powerful others externality (e.g. “health professionals control my health”) and chance externality (e.g. “If it is meant to be I will stay healthy”). Acceptable levels of
reliability and validity have been reported for this measure (29,31). In the present study, the internal consistencies for the 3 subscales were as follows: 0.67 internal, 0.72 chance external and 0.66 powerful others external. Adolescent and family characteristics Parents completed a questionnaire that asked about maternal and paternal education level, maternal and paternal marital status and family income. The adolescents answered questions about their age and completed the Pubertal Development Scale. This scale includes items for both boys and girls to answer, which inquire about height, growth, body hair growth and skin changes (32). Two additional items that are specific to boys’ development and 3 items specific to girls’ development also are included. Participants respond on a 4-point Likert scale, which ranges from 1 (“not yet started”) to 4 (“seems complete”). The item that inquires about the onset and age of menarche in girls does not use a Likert scale. Based on their scores, adolescents are classified as prepubertal, early pubertal, midpubertal, late pubertal and postpubertal. The categoric maturation scores are designed to be similar to Tanner staging categories. The validity of the Pubertal Development Scale is supported by strong correlations between physician and adolescent self-reports of pubertal stage, as well as parent and adolescent reports (32). The Pubertal Development Questionnaire was included in the present study to ensure that there were no significant differences in pubertal stage between adolescents with type 1 diabetes and comparison adolescents that should be controlled for in statistical analysis. Statistical analyses Chi squares and analyses of variance were used to investigate group differences on adolescent and family variables. Analyses of variance also were used to investigate group differences on body image and eating disorder symptoms and differences in the measures of social self-concept, social support and locus of control. Regression analysis and correlations were used to examine the associations among measures of self-concept, social support and locus of control, and body image and eating disorder symptoms. Correlation analyses were conducted to investigate relationships between eating disorder symptoms and body image. Results Characteristics of adolescents and their families No differences were found between adolescents with type 1 diabetes and healthy comparison adolescents on any variables examined (Table 1). Eating disorder symptoms and body image On the EDI-III, adolescents with diabetes did not report significantly greater symptoms of bulimia or body dissatisfaction compared with the comparison group (Table 2). There was a trend for adolescents with diabetes to have a greater drive for thinness. For both groups, average scores on the EDI-III subscales were in the normal range. Seven participants with diabetes (15%) and 3 comparison participants (11%) had increased scores on at least 1 of the EDI-III subscales. These individuals were seen for further assessment of their eating disorder symptoms and were offered intervention if a need was identified. No significant differences were found between adolescents with diabetes and the comparison group on the measure of body image (i.e. BESAA) (Table 2). For both groups, total scores were in the normal range. Because no significant differences were found between the adolescents with diabetes and the comparison adolescents on the
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Table 1 Family and Adolescent Characteristics Variable Family Demographic Variables Mother’s Education Level n. (%) < High School High School Some Post Secondary Post Secondary Diploma University Degree Father’s Education Level n. (%) < High School High School Some Post Secondary Post Secondary Diploma University Degree Mother’s Marital Status n. (%) Married Never Married Separated Divorced Common Law Widowed Father’s Marital Status n (%) Married Never Married Separated Divorced Common Law Widowed Family Income Per Year, n (%) $10-20,000 $21-30,000 $31-40,000 $41-50,000 $51-60,000 $61-70,000 $71-80,000 $81-90,000 $91,000+ Adolescent Descriptive Variables Age Pubertal Stage Mean (SD). Pre-Pubertal Early Pubertal Mid Pubertal Late Pubertal Post Pubertal Body Mass Index Mean (SD) Weight (pounds) Height (feet)
Diabetes (n¼ 46)
Comparison (n¼27)
F and X2 values X2(4, n¼73)¼1.32, p¼.86
5 10 2 10 19
(10.9) (21.7) (4.3) (21.7) (41.3)
4 5 2 6 10
(14.8) (18.5) (7.4) (22.2) (37.0)
3 7 3 10 22
(6.6) (15.6) (6.7) (22.2) (48.9)
3 2 0 9 13
(11.1) (7.4) (0) (33.3) (48.1)
40 1 2 2 0 0
(88.9) (2.2) (4.4) (4.4) (0) (0)
20 1 2 2 1 1
(74.0) (3.7) (7.4) (7.4) (3.7) (3.7)
40 1 2 1 0 0
(90.9) (2.3) (4.5) (2.3) (0) (0)
22 0 2 2 1 0
(81.5) (0) (7.4) (7.4) (3.7) (0)
0 1 2 2 3 5 4 5 20
(0) (2.4) (4.8) (4.8) (7.1) (11.9) (9.5) (11.9) (47.6)
2 0 0 2 2 0 3 2 16
(7.4) (0) (0) (7.4) (7.4) (0) (11.1) (7.4) (59.3)
X2(4, n¼73)¼4.37, p¼.50
X2(5, n¼72)¼6.72, p¼.24
X2(5, n¼71)¼3.70, p¼.45
X2(8, n¼71)¼10.92, p¼.21
15.00 (1.70) 1 1 12 12 20 22.42 136.10 5.41
(2.2) (2.2) (26.1) (26.1) (43.5) (3.95) (27.04) (.33)
measures of eating disorder symptoms and body image, they were combined into 1 group and the correlations between body image and the 3 EDI subscales were examined. Significant negative correlations were found between body image and body dissatisfaction (r¼0.76, p
Contents lists available at ScienceDirect
Canadian Journal of Diabetes journal homepage: www.canadianjournalofdiabetes.com
Original Research
Psychological Correlates of Eating Disorder Symptoms and Body Image in Adolescents with Type 1 Diabetes Laura A. Kaminsky PhD a, b, *, Deborah Dewey PhD c, d, e a
Department of Paediatrics, University of Calgary, Calgary, Alberta, Canada Diabetes Clinic, Alberta Children’s Hospital, Calgary, Alberta, Canada Departments of Paediatrics and Community Health Sciences, University of Calgary, Calgary, Alberta, Canada d Behavioural Research Unit, Alberta Children’s Hospital, Calgary, Alberta, Canada e Alberta Children’s Hospital Research Institute for Child and Maternal Health, Alberta, Canada b c
a r t i c l e i n f o
a b s t r a c t
Article history: Received 1 March 2013 Received in revised form 24 June 2013 Accepted 28 June 2013
Objective: To examine eating disorder symptoms and body image in adolescents with type 1 diabetes and to investigate the associations among social support, self-esteem, health locus of control, eating disorder symptoms and body image. Methods: Forty-six adolescents with type 1 diabetes and 27 healthy comparison adolescents completed questionnaires. Results: No significant differences were identified in eating disorder symptoms and body image between adolescents with type 1 diabetes and healthy comparison adolescents. Regression analyses were completed with the full sample of adolescents with type 1 diabetes and healthy comparison adolescents. Higher levels of social support and being male were associated with a more positive body image, less body dissatisfaction and a lower drive for thinness. A belief by the adolescents that parents or healthcare providers (i.e. external powerful others locus of control) were in control of their health was associated with a more positive body image and less body dissatisfaction. Higher self-esteem was associated with a greater drive for thinness and a higher level of body dissatisfaction. Conclusions: Social support, health locus of control and self-esteem appear to be important correlates of eating disorder symptoms and body image in adolescents with diabetes and their typically developing peers. Ó 2013 Canadian Diabetes Association
Keywords: adolescents body image eating disorders type 1 diabetes
r é s u m é Mots clés : adolescents image corporelle troubles du comportement alimentaire diabète de type 1
Objectif : Examiner les symptômes du trouble de comportement alimentaire et l’image corporelle chez les adolescents ayant le diabète de type 1 et explorer les liens entre le soutien social, l’estime de soi, le locus de contrôle de la santé, et les symptômes du trouble du comportement alimentaire et l’image corporelle. Méthodes : Quarante-six (46) adolescents ayant le diabète de type 1 et 27 adolescents témoins en santé ont rempli les questionnaires. Résultats : Aucune différence significative n’a été observée dans les symptômes du trouble du comportement alimentaire et l’image corporelle entre les adolescents ayant le diabète de type 1 et les adolescents témoins en santé. Les analyses de régression ont été effectuées à partir de l’échantillon complet des adolescents ayant le diabète de type 1 et des adolescents témoins en santé. Les niveaux plus élevés de soutien social et du fait d’être de sexe masculin ont été associés à une image corporelle plus positive, à moins d’insatisfaction corporelle et à une plus faible volonté de mincir. Le fait pour les adolescents de croire que les parents ou les prestataires de soins (c.-à-d. d’autres locus de contrôle externes forts) prenaient en charge leur santé a été associé à une image corporelle plus positive et à moins d’insatisfaction corporelle. Une plus grande estime de soi a été associée à une plus grande volonté de mincir et à un niveau plus élevé d’insatisfaction corporelle. Conclusions : Le soutien social, le locus de contrôle de la santé et l’estime de soi semblent être d’importants corrélats des symptômes du trouble du comportement alimentaire et de l’image corporelle chez les adolescents et leurs pairs ayant un développement normal. Ó 2013 Canadian Diabetes Association
* Address for correspondence: Laura A. Kaminsky, PhD, Diabetes Clinic, Alberta Children’s Hospital, 2888 Shaganappi Trail NW, Calgary, Alberta T2T 5C7, Canada. E-mail address: [email protected]. 1499-2671/$ e see front matter Ó 2013 Canadian Diabetes Association http://dx.doi.org/10.1016/j.jcjd.2013.06.011
L.A. Kaminsky, D. Dewey / Can J Diabetes 37 (2013) 408e414
Introduction Type 1 diabetes is a common chronic illness of childhood (1). It is managed by a complex treatment regimen that aims at maintaining good glycemic control to reduce the risk of short- and long-term medical complications. Adolescence is a particularly challenging time for maintaining optimal glycemic control as a result of physiological changes and a decrease in diabetes treatment adherence secondary to various psychosocial factors (2). Intensified treatment protocols for type 1 diabetes have been found to result in weight gain, which may be distressing to adolescents. To control weight, some adolescents with diabetes omit insulin or engage in disordered eating behaviours, such as reducing caloric intake or binge eating (3). Studies focusing exclusively on adolescent girls found that 10% to 14% reported deliberate insulin omission as a weight control practice (4e6). Additional factors that may contribute to the development of disordered eating in adolescents with type 1 diabetes are the dietary focus and dietary restraints required by the treatment regimen (7), pubertal changes (8) and internalization of media messages that express a cultural ideal of thinness (9). The prevalence of eating disorders in adolescents with type 1 diabetes ranges from 14% to 27% (5,10,11). In contrast, the rates of specific eating disorders in healthy adolescent females are 0.3% for anorexia nervosa, 1% for bulimia nervosa and 2.4% for an eating disorder not otherwise specified (12). Adolescent girls with type 1 diabetes have been reported to be at higher risk of developing eating disorders than healthy adolescent females (10,13); however, this has not been supported consistently in the research literature (11,14). Adolescents with type 1 diabetes who develop eating disorders are at high risk for developing both acute and long-term complications of diabetes including retinopathy and nephropathy (10,15e17). Thus, eating disorders can play a significant role in the diabetes health outcomes of adolescents. Body image is defined as an individual’s perspective and feelings about their body (18). Much of the research on body image has examined body dissatisfaction, that is, having a negative body image typically associated with a desire to be thinner (18). Body dissatisfaction is more common in adolescents with chronic illnesses than in healthy adolescents, and distortions in body image, body dissatisfaction and preoccupation with body weight have been linked to eating disorders (i.e. anorexia nervosa, bulimia nervosa) and milder eating disturbances (i.e. eating disorder not otherwise specified, subclinical eating disorders) (18). Recent reviews have linked deficits in self-concept and lower self-esteem, which often are used interchangeably, to an increased vulnerability to eating disturbances (8,19,20). There is limited research, however, on whether these and other factors such as social support and locus of control are protective against eating disturbances and body image distortions. Maharaj et al (17) found that self-concept deficits, maternal disordered eating or maternal weight control behaviours and impaired mother-daughter relationships were significant predictors of eating disorders in adolescent girls with type 1 diabetes. Olmsted et al (21) reported that lower self-esteem related to physical appearance, lower overall self-esteem, depression, and weight and shape concerns were more common among 9to 13-year-old girls with type 1 diabetes who developed disordered eating over a 5-year period. However, social acceptance from peers was not associated significantly with disordered eating. Gerner and Wilson (22) found that in girls without any chronic health conditions, lower peer acceptance, perceived social support from friends and friendship intimacy were associated with body image concerns. These findings suggest that self-esteem and social support could be important factors in facilitating a healthy adjustment in adolescents with type 1 diabetes. To date, no studies have examined whether locus of control and overall social support (i.e.
409
support from parents, teachers and peers) are associated with eating disorders and body image in adolescents with type 1 diabetes; however, a review of the literature suggested that these correlates are worthy of study (23). The main purpose of the present study was to investigate eating disorder symptoms and body image in adolescents with type 1 diabetes. It was hypothesized that adolescents with type 1 diabetes would report significantly more symptoms of eating disorders and a less positive body image compared with adolescents without health problems. It also was hypothesized that higher self-esteem and social support, and an internal locus of control (an individual’s belief that they have the ability to control and impact their health) (24) would be associated with fewer body image concerns and fewer symptoms of eating disorders. A cross-sectional descriptive study using adolescents’ self-reports on questionnaires was used to examine the hypotheses. This study adds to the literature because it investigates protective factors that may be associated with eating disorder symptoms and body image in adolescents with type 1 diabetes. Methods Participants Adolescents, 12 to 18 years of age, were recruited from a pediatric hospital diabetes clinic. The clinic population is 49.8% female and 50.2% male. All participants had been diagnosed with diabetes for at least 6 months. Approximately 90% of the clinic population is Caucasian and 10% are from other ethnic backgrounds. Three hundred adolescents with diabetes were selected randomly from the clinic database and were approached as potential participants. Twenty-seven adolescent girls and 19 adolescent boys (mean age, 15 years; standard deviation, 1.62) volunteered to participate in the study. Adolescents from the orthopedics clinic were chosen as a comparison sample because they were treated in the same hospital setting as the patient with diabetes but not for a chronic health condition. Four hundred potential comparison participants from the orthopedics clinic were contacted. Twenty-seven adolescents, 13 girls and 14 boys, between 12 and 18 years of age (mean age, 14.9 years; standard deviation, 1.64) volunteered to participate. These adolescents had been seen for bone fractures and were no longer active patients. There were no limitations on their physical activity or ambulation at the time of their participation. Most comparison participants did not have chronic health conditions; however, 2 had asthma and 1 had a chronic orthopedic condition. The study was approved by the University of Calgary Conjoint Health Research Ethics Board. Procedures Consent/assent forms and questionnaires were mailed to the families. Questionnaires were mailed to potential participants from the diabetes and orthepedic clinic. Two weeks after the initial questionnaire package was sent, a reminder telephone call was made to all families asking them to return the questionnaires. No compensation was offered to participants. Parents provided informed consent; adolescents completed the assent form and the questionnaires independently. The Eating Disorders Inventory-II, Body Esteem Scale for Adolescents and Adults, Social Support Scale for Children, Self-Perception Profile for Adolescents, Multidimensional Health Locus of Control Scale and Pubertal Development Scale were completed by the adolescents. Parents completed a demographics questionnaire. The questionnaires were returned to the investigators in a stamped return envelope. Families were invited to contact the principal investigator if they had any concerns or questions about the study.
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L.A. Kaminsky, D. Dewey / Can J Diabetes 37 (2013) 408e414
Measures Primary outcomes The Eating Disorder Inventory-III (EDI-III) contains 91 items that assess attitudes and behaviours associated with eating disorders and questions about height and weight, which was used to calculate body mass index (25). The EDI-III is composed of 3 Eating Disorder Risk Scales (i.e. Body Dissatisfaction, Drive for Thinness and Bulimia). Participants rate their level of agreement with test items on a 6-point Likert scale (ranging from “always” to “never”). The EDI-III is a reliable and valid measure of eating disorder symptoms and body attitudes. Internal consistencies in the present study for the 3 subscales were as follows: 0.76 for the Body Dissatisfaction scale, 0.71 for the Drive for Thinness scale and 0.79 for the Bulimia scale. The Body Esteem Scale for Adolescents and Adults (BESAA) was used to assess body image (26). It includes 23 statements. Individuals rate how often they agree with each statement on a 5point Likert scale ranging from never (0) to strongly agree (4). The questionnaire is divided into 3 main categories: body esteem (BE) regarding appearance (e.g. “I feel ashamed of how I look”), BE regarding weight (e.g. “I really like what I weigh”) and BE regarding attribution (e.g. “Other people consider me good looking”). Factor analysis has shown 3 factors that correspond to these 3 categories (24). The BESAA total score was used for the purposes of this study. High internal consistency was found for each category with Cronbach alpha reliability coefficients of 0.92 for BE regarding appearance, 0.94 for BE regarding weight and 0.81 for BE regarding attribution. Test-retest reliabilities for the categories were high (BE regarding appearance: r ¼ 0.89, BE regarding weight: r ¼ 0.92, and BE regarding attribution: r ¼ 0.83 and convergent validity was established by comparing participants’ results on this measure with their results on 2 general measures of self-esteem, the Rosenberg Self-Esteem Scale and the Global Self-Worth subscale of the SelfPerception Profile for College Students (24). Alpha reliability for the BESAA total score was 0.78 in this study. Correlates of eating disorders symptoms and body image The Social Support Scale for Children, a 24-item self-report scale, assesses children’s and adolescents’ perceptions of support from their parents, teachers, classmates and a close friend (27). Six items are used to measure each of these 4 sources of support. Children are asked to choose which of 2 opposing statements are true for them and then to identify whether the statement is “sort of true” or “really true.” Higher scores indicate greater social support. The overall score on this measure of social support was used in the present study. Children’s overall scores have been found to correlate moderately with children’s reports of self-worth. Alpha reliability for the overall social support scale in this study was 0.75. The Self-Perception Profile for Adolescents is a 45-item selfreport scale that assesses an adolescents’ sense of self-esteem (28). It includes an overall self-esteem scale, Global Self-Worth, which was used in the present study. Adolescents were asked to choose which of 2 opposing statements are true for them and then to identify whether the statement was “sort of true” or “really true.” Harter (28) reported that the measure has good validity and reliability. The alpha reliability for the Global Self-Worth scale in the present study was 0.78. The Multidimensional Health Locus of Control, Form A (29,30) consists of 18 questions about individuals’ perceptions of their control over their health. Individuals responded on a 6-point Likert scale ranging from (“strongly disagree” to “strongly agree”). Three 6-item subscales are contained in the measure (internality; e.g. “I am in control of my health”), powerful others externality (e.g. “health professionals control my health”) and chance externality (e.g. “If it is meant to be I will stay healthy”). Acceptable levels of
reliability and validity have been reported for this measure (29,31). In the present study, the internal consistencies for the 3 subscales were as follows: 0.67 internal, 0.72 chance external and 0.66 powerful others external. Adolescent and family characteristics Parents completed a questionnaire that asked about maternal and paternal education level, maternal and paternal marital status and family income. The adolescents answered questions about their age and completed the Pubertal Development Scale. This scale includes items for both boys and girls to answer, which inquire about height, growth, body hair growth and skin changes (32). Two additional items that are specific to boys’ development and 3 items specific to girls’ development also are included. Participants respond on a 4-point Likert scale, which ranges from 1 (“not yet started”) to 4 (“seems complete”). The item that inquires about the onset and age of menarche in girls does not use a Likert scale. Based on their scores, adolescents are classified as prepubertal, early pubertal, midpubertal, late pubertal and postpubertal. The categoric maturation scores are designed to be similar to Tanner staging categories. The validity of the Pubertal Development Scale is supported by strong correlations between physician and adolescent self-reports of pubertal stage, as well as parent and adolescent reports (32). The Pubertal Development Questionnaire was included in the present study to ensure that there were no significant differences in pubertal stage between adolescents with type 1 diabetes and comparison adolescents that should be controlled for in statistical analysis. Statistical analyses Chi squares and analyses of variance were used to investigate group differences on adolescent and family variables. Analyses of variance also were used to investigate group differences on body image and eating disorder symptoms and differences in the measures of social self-concept, social support and locus of control. Regression analysis and correlations were used to examine the associations among measures of self-concept, social support and locus of control, and body image and eating disorder symptoms. Correlation analyses were conducted to investigate relationships between eating disorder symptoms and body image. Results Characteristics of adolescents and their families No differences were found between adolescents with type 1 diabetes and healthy comparison adolescents on any variables examined (Table 1). Eating disorder symptoms and body image On the EDI-III, adolescents with diabetes did not report significantly greater symptoms of bulimia or body dissatisfaction compared with the comparison group (Table 2). There was a trend for adolescents with diabetes to have a greater drive for thinness. For both groups, average scores on the EDI-III subscales were in the normal range. Seven participants with diabetes (15%) and 3 comparison participants (11%) had increased scores on at least 1 of the EDI-III subscales. These individuals were seen for further assessment of their eating disorder symptoms and were offered intervention if a need was identified. No significant differences were found between adolescents with diabetes and the comparison group on the measure of body image (i.e. BESAA) (Table 2). For both groups, total scores were in the normal range. Because no significant differences were found between the adolescents with diabetes and the comparison adolescents on the
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Table 1 Family and Adolescent Characteristics Variable Family Demographic Variables Mother’s Education Level n. (%) < High School High School Some Post Secondary Post Secondary Diploma University Degree Father’s Education Level n. (%) < High School High School Some Post Secondary Post Secondary Diploma University Degree Mother’s Marital Status n. (%) Married Never Married Separated Divorced Common Law Widowed Father’s Marital Status n (%) Married Never Married Separated Divorced Common Law Widowed Family Income Per Year, n (%) $10-20,000 $21-30,000 $31-40,000 $41-50,000 $51-60,000 $61-70,000 $71-80,000 $81-90,000 $91,000+ Adolescent Descriptive Variables Age Pubertal Stage Mean (SD). Pre-Pubertal Early Pubertal Mid Pubertal Late Pubertal Post Pubertal Body Mass Index Mean (SD) Weight (pounds) Height (feet)
Diabetes (n¼ 46)
Comparison (n¼27)
F and X2 values X2(4, n¼73)¼1.32, p¼.86
5 10 2 10 19
(10.9) (21.7) (4.3) (21.7) (41.3)
4 5 2 6 10
(14.8) (18.5) (7.4) (22.2) (37.0)
3 7 3 10 22
(6.6) (15.6) (6.7) (22.2) (48.9)
3 2 0 9 13
(11.1) (7.4) (0) (33.3) (48.1)
40 1 2 2 0 0
(88.9) (2.2) (4.4) (4.4) (0) (0)
20 1 2 2 1 1
(74.0) (3.7) (7.4) (7.4) (3.7) (3.7)
40 1 2 1 0 0
(90.9) (2.3) (4.5) (2.3) (0) (0)
22 0 2 2 1 0
(81.5) (0) (7.4) (7.4) (3.7) (0)
0 1 2 2 3 5 4 5 20
(0) (2.4) (4.8) (4.8) (7.1) (11.9) (9.5) (11.9) (47.6)
2 0 0 2 2 0 3 2 16
(7.4) (0) (0) (7.4) (7.4) (0) (11.1) (7.4) (59.3)
X2(4, n¼73)¼4.37, p¼.50
X2(5, n¼72)¼6.72, p¼.24
X2(5, n¼71)¼3.70, p¼.45
X2(8, n¼71)¼10.92, p¼.21
15.00 (1.70) 1 1 12 12 20 22.42 136.10 5.41
(2.2) (2.2) (26.1) (26.1) (43.5) (3.95) (27.04) (.33)
measures of eating disorder symptoms and body image, they were combined into 1 group and the correlations between body image and the 3 EDI subscales were examined. Significant negative correlations were found between body image and body dissatisfaction (r¼0.76, p
