© American Diabetes Association ®, Inc., 2002 Eating Disorders in Adolescent Girls and Young Adult Women With Type 1 Diabetes
Dennis Daneman, MB, BCh, FRCPC Gary Rodin, MD, FRCPC Teens with type 1 diabetes face two clashing realities. On the one hand, the results of studies such as the Diabetes Control and Complications Trial (DCCT) provide irrefutable evidence of the link between diabetes control and the onset and progression of diabetes-related microvascular complications.1 The DCCT message was loud and clear: Control counts! On the other hand, there are numerous studies, including the DCCT, demonstrating that, during adolescence, metabolic control tends to be poorest and that the goals of intensive diabetes management are more difficult to achieve.2,3 What are the reasons for poor glycemic control in adolescents with type 1 diabetes? I believe that it results from the complex interplay between biological (e.g., insulin resistance of puberty) and psychosocial (e.g., noncompliance, family environment) factors. Our group has focused on one specific contributing factor, namely, eating disorders in teenage girls with type 1 diabetes. This From Research to Practice section offers a review of this topic by our research group at the University of Toronto. This is a departure from the usual format of Diabetes Spectrum research sections in that the entire section comprises contributions from a single research group. A number of groups around the world have made substantial contributions to this field, and we have been as diligent as possible in citing their enormous contributions. However, we do hope that our group has been able to provide a unifying view of the pathophysiology and impact of eating disturbances in girls and young women with type 1 diabetes. Our aim is to sensitize readers to the manifestations of this common co-morbidity and to highlight areas where further research is warranted. Because this monograph-style presentation represents the combined efforts of all of the authors, we have listed only the primary contributors to the writing of each section. We have provided a single reference list at the end of the discussion to avoid unnecessary repetition of citations. In addition to myself, contributors to this research section include Gary Rodin, MD, FRCPC; Jennifer Jones, PhD; Patricia Colton, MD; Anne Rydall, MSc; Sherry Maharaj, PhD; and Marion Olmsted, PhD of the Eating Disorders and Diabetes Research Group at the University of Toronto; the University Health Network; and the Hospital for Sick Children, in Toronto.
Since the early 1980s, there has been increasing attention paid to the possible relationship between type 1 diabetes and eating disorders in young women. Initial interest was sparked by individual case reports of adolescent girls or young adult women with diabetes who also suffered from anorexia nervosa.46 The outcome of this combination is often catastrophic, with poor metabolic control, growth delay, recurrent diabetic ketoacidosis (DKA), earlier-than-expected onset of diabetes-related complications, and premature mortality. These clinical observations sparked a more systematic attempt to define the relationship between diabetes and eating disorders. Subsequent research by our group and others has allowed us to reach the following evidence-based conclusions:
This From Research to Practice section presents a review of the data regarding eating disorders in young women with type 1 diabetes in order to alert health care professionals to the prevalence, presentation, and associated problems of this co-morbidity. The contributors to this monograph are all members of the Eating Disorders and Diabetes Research Group at the University of Toronto that comprises a multidisciplinary team of health care professionals including a pediatric endocrinologist (DD), psychiatrist (GR), clinical psychologists (MO, SM), research coordinator (AR), population health scientist (JJ), and graduate students and postdoctoral fellows (AR, JJ, SM, PC). We include here a description of our model for the interaction between type 1 diabetes and eating disorders, a review of the evidence to support this linkage, and consideration of its relevance for health care professionals involved in the care of adolescent girls and young adult women with type 1 diabetes.
1. Model for the Interaction Between Type 1 Diabetes and Eating Disorders
Primary contributors: Jennifer Jones, PhD, and Patricia Colton, MD
In Brief A substantial number of studies have investigated the prevalence of eating disorders in adolescent girls and young adult women with type 1 diabetes. Systematic studies have determined that eating disturbances, including subthreshold and clinical (full-syndrome) eating disorders as well as milder behavioral disturbances, are common in young women with diabetes and are associated with poor metabolic control and increased long-term diabetes-related morbidity and mortality. However, the results of studies that have compared the prevalence of eating disorders in adolescent girls and adult women with type 1 diabetes to that of their peers without diabetes have varied considerably.7,2329 The outcomes of these studies appear to depend heavily on the sample studied, the methodology employed, and the diagnostic criteria for eating disorders applied. A few studies have assessed the occurrence of diabetes in clinical samples of patients with eating disorders. Not surprisingly, virtually all have failed to show a high prevalence of type 1 diabetes.5,3033 However, in the majority of studies that have assessed eating psychopathology in samples with diabetes, the results have been more varied. While some of these studies have shown similar rates of eating disturbances as those reported in populations without diabetes,3437 others have reported significantly higher rates.10,22,31,3843 Most of the early studies relied on self-report measures rather than standardized interviews to diagnose eating disorders and did not include control groups. Further, all of these studies have had relatively small samples of female subjects with diabetes within the age range at highest risk for eating disorders, namely, older adolescence and young adulthood. This has limited their generalizability and power to detect meaningful differences.
i. Methodological Considerations
In studies using the broad DSM-III criteria, a diagnosis of an eating disorder was made in 1735% of females with type 1 diabetes.38,39,42,43 The rate fell to 516% in studies using the far stricter DSM-III-R criteria.8,22-24,47,48 Finally, studies using DSM-IV criteria have reported the prevalence of eating disorders to range from 711% of adolescent and young adult females with type 1 diabetes.7,29,49 In all of the studies employing DSM-IV criteria, bulimia nervosa and ED-NOS are much more common than anorexia nervosa. This finding is not surprising, given that bulimia nervosa and its variants are more common than anorexia nervosa in the general population.46,50 In addition, the dietary dysregulation related to diabetes and the availability of insulin omission for purging may specifically increase the risk of bulimia-spectrum disorders rather than that of restricting-type disorders, such as anorexia nervosa.
ii. Controlled Prevalence Studies Using Diagnostic Interviews
Peveler and colleagues24 conducted a cross-sectional survey to determine the prevalence of eating disorders in 33 female and 43 male adolescents aged 1118 years with type 1 diabetes, compared to 76 matched control subjects without diabetes. Features of eating disorders were not found in any of the male subjects. In the females, no subjects met criteria for anorexia nervosa or bulimia nervosa, but 9% of the adolescent girls with diabetes and 6% of the female control subjects met criteria for ED-NOS. This 50% difference between groups was not statistically significant, leading the authors to conclude that the prevalence of eating disorders is not increased in young women with type 1 diabetes. However, this study had only a 7.5% chance of detecting a significant difference of this magnitude, based on the sample size and the prevalence rates found. Further, although 12% of the sample with diabetes admitted to current manipulation of insulin dose for weight and shape reasons, the DSM-III-R criteria used in this study did not include the manipulation of medication (including insulin) as an inappropriate compensatory behavior. These methodological factors may account for a lower prevalence rate in the diabetes sample and for the lack of a statistically significant difference between the diabetes and control groups. The same research group reported a similar study of an older group of 54 females with type 1 diabetes and 67 control subjects aged 1825 years,23 in which DSM-III-R eating disorders were diagnosed in 11% of the subjects with diabetes and in 7.5% of the control subjects. Again, this difference was not statistically significant, although the study had very low power (<20%) to detect the observed difference. Striegel-Moore et al.25 studied 46 girls with diabetes aged 818 years and 46 control subjects using the Eating Disorder Examination interview.51 No cases of eating disorders were detected in either group. However, 6.5% of the subjects with diabetes reported insulin misuse within the previous month. Only two of the control subjects and none of the subjects with diabetes reported feeling a loss of control over eating, and 33% of the girls with diabetes compared to 24% of the control subjects reported excessive weight control within the past month. While the authors suggested that there does not appear to be an increased prevalence of eating disorders in the diabetes population, they did concede that the relatively small sample size raises questions regarding the generalizability of their findings. Similar findings were reported by Vila and colleagues, who published two studies on the prevalence of eating disorders in young women with type 1 diabetes.26,28 In both, all subjects were within the age of highest risk for eating disorders and were interviewed using a semi-structured interview based on DSM-III-R diagnostic criteria. Eating disorders were diagnosed in 8% of the subjects with diabetes in both studies. No eating disorder cases were detected in the control group studied in 1993, and only 2% of control subjects met eating disorder criteria in the 1995 study. Although these findings were not statistically significant, the authors concluded that girls with diabetes are likely at increased risk for eating disorders. Mannucci and colleagues27 conducted a study of 62 men and women with diabetes and 148 control subjects without diabetes, aged 1560 years. The authors found that 1.6% of the subjects with diabetes and 0.9% of the control subjects met DSM-III-R criteria for anorexia nervosa; bulimia nervosa was diagnosed in 1.6% of the subjects with diabetes and 2.7% of controls; and ED-NOS was diagnosed in 4.9 and 2.7%, respectively. In addition, 33% of the subjects with diabetes met criteria for subthreshold disorders, compared to 22.5% of the control subjects. The average age of the subjects with diabetes was 34 years, which is beyond the peak age of highest risk for eating disorders, and the control sample was not randomly selected. Further, the inclusion of both men and women likely diluted the findings given the low risk of eating disorders in men. In a recently published population-based study by Engstrom and colleagues,29 89 adolescent females with type 1 diabetes and 89 matched control subjects completed an eating disorder screening package. Subjects who scored above a predetermined cut-off were then asked to complete a semi-structured diagnostic interview. None of the control subjects met criteria for a DSM-IV eating disorder, whereas 7% of the subjects with diabetes met criteria for ED-NOS. There were no cases of anorexia nervosa or bulimia nervosa in either group. However, due to the small sample of subjects who were actually interviewed (including only two control subjects), the validity and reliability of this study are questionable, and these findings must be interpreted with caution. The results of the above studies are difficult to interpret given their relatively small sample sizes. However, when we combined the results of these first seven prevalence studies,2329 we found that 28 of 388 subjects with diabetes (7.2%) and 17 of 453 control subjects (3.7%) met criteria for an eating disorder, giving an odds ratio (OR) of 1.99 (CI 1.13.7). Furthermore, when subthreshold eating disorders were documented, these were found in 56 of 212 (26.4%) and 40 of 242 (16.5%) of the diabetes and control groups, respectively, giving an OR of 1.78 (CI 1.12.8). The inconclusive findings reported above and the elevated ORs of the combined studies provided the impetus for us to perform a study with sufficient power to definitively answer the question of whether eating disorders are more common among adolescent females with type 1 diabetes than among their peers without diabetes. This allowed us to test the hypotheses for disease causation or interaction as illustrated in the model in Figure 1 (p. 85). In a large, multi-site, case-controlled study, we assessed the prevalence of disturbed eating attitudes, behavior, and clinical and subthreshold eating disorders in 356 adolescent girls with type 1 diabetes and 1,098 age-matched control subjects.7 The girls with diabetes were recruited from three large diabetes clinics in major cities in Canada (Toronto, Hamilton, and Ottawa), and the control subjects were recruited from eighteen schools distributed in these cities. The most striking finding was that DSM-IV eating disorders (see Table 1 for diagnostic criteria) were more than twice as common in the diabetes sample as in the control group. Ten percent of the subjects with diabetes compared to 4.5% of control subjects met criteria for a DSM-IV eating disorder (OR=2.4, CI 1.5-3.8). All of these disorders were bulimia nervosa or ED-NOS; no cases of full-syndrome anorexia nervosa were identified. An additional 14% of the diabetes group and 8% of the control subjects were engaging in disordered eating behavior that met criteria for a subthreshold disorder (OR=1.9, CI 1.3-2.8). This study is the first to have a large enough sample size of females in the age of highest risk for eating disorders to adequately address the question of prevalence. Of note, the prevalence rates of eating disorders in the diabetes and control groups in our study were similar to those reported elsewhere.23,24,2629 However, the previous studies lacked the sample sizes, and thus the power, to achieve statistical significance for observed differences between groups.
iii. Pre-Teens and Early Teens With Type 1 Diabetes We are presently carrying out a study of eating attitudes and behavior in a group of girls with diabetes aged 913 years. Preliminary analysis of the first 90 subjects suggests that weight- and shape-related body image disturbances are very common in this group, reported by almost half the subjects. In addition, although clinical eating disorders are very uncommon in this age group, almost one in six girls reported at least one current disturbed eating behavior, including dieting, binge eating, insulin omission, and intense, abnormal exercise for weight control.12
Summary
Primary contributor: Anne Rydall, MSc
In Brief The Diabetes Control and Complications Trial (DCCT),1,3,52 a 9-year, multi-center, randomized controlled trial of more than 1,400 individuals with type 1 diabetes, provided the most conclusive evidence that the risk of diabetes-related microvascular complications is closely linked to the level of long-term metabolic control. With intensive diabetes management, the DCCT1 clearly demonstrated that the onset of retinopathy can be significantly delayed by 76%, its progression slowed by 54%, and the development of proliferative and severe non-proliferative retinopathy reduced by 47%. In addition, intensive treatment reduced the occurrence of microalbuminuria and clinical nephropathy by 3954% and clinical neuropathy by 60%. Furthermore, the DCCT found that the cohort receiving intensive treatment during the trial continued to show a significantly lower risk of progression of retinopathy and nephropathy 4 years after conclusion of the study, compared to those who had received conventional treatment.53
i. Disordered Eating and Compensatory Weight-Loss Behavior In a study of adolescent girls aged 1218 years (mean age 15 years) with type 1 diabetes,10 we found that 45% of subjects admitted to binge eating, 38% to dieting for weight control, and 8 and 2% to self-induced vomiting and laxative abuse, respectively. Of note in this group, 14% admitted to deliberate insulin omission for the purpose of inducing glycosuria as a means of controlling weight. We re-evaluated this same cohort 4 years later (mean age 19 years at follow-up) and found significant increases in the percentage of subjects admitting to disordered eating and weight-loss behavior, including binge eating (now 53%), insulin omission (now 34%), and dieting (now 54%) (Figure 2).
(a) Deliberate insulin omission for weight control Individuals with type 1 diabetes have a unique weight control method available to them, namely, the deliberate omission or reduction of insulin in an effort to induce glycosuria, a form of calorie purging. This has been recognized in the Diagnostic and Statistical Manual of Mental Disorders (Fourth Edition) (DSM-IV) eating disorder criteria46 as an inappropriate compensatory purging behavior included under "misuse of medications for weight loss." Individuals with diabetes are often aware that insulin therapy can lead to weight gain20,21,54 and that reduction or omission of their prescribed insulin dosage can result in weight loss.17,22 This extremely dangerous method of promoting weight loss or preventing weight gain is common among young women with diabetes, with reported rates ranging from 5 to 39%, depending on the age range of the samples studied.7,10,2224,42,43,48,55,56 In general, the studies that include a predominantly mid-adolescent cohort have yielded prevalence rates of insulin omission in the 1115% range,7,10,22,24,25 whereas those including a somewhat older cohort (older adolescents and young adults) have reported considerably higher rates in the 3039% range.10,11,23,55 Further-more, in a preliminary study of pre-teen and early teenage girls with type 1 diabetes (mean age 11.8 years), we have found that insulin omission occurs with a frequency of only 1%.12 Taken together, these studies suggest that insulin omission is a problem of increasing importance as these girls make the transitions from early to mid-adolescence and into young adulthood. Figure 3 shows the prevalence of insulin omission in these different age groups taken from the studies performed by our group.10,12
Apart from dieting for weight loss, deliberate insulin omission is the most commonly employed weight-loss strategy among adolescent girls and young adult women with diabetes.7,10,22,23 The easy availability of this weight-loss method may explain the lower prevalence of other purging behaviors, such as extreme exercise, self-induced vomiting, and laxative or diuretic use, reported among young women with diabetes.7,17,22,23
(b) Binge eating It has been suggested that the quantity of food consumed during a binge episode should not be considered of diagnostic significance.5962 This seems particularly relevant for individuals with diabetes, for whom binges frequently involve the consumption of much smaller quantities of food than would normally be associated with an eating disorder.17 Even binges of smaller quantity can involve feeling a loss of control, guilt, self-loathing, and a desire to purge,62 and when associated with diabetes, are still likely to affect metabolic control. Furthermore, among some individuals with diabetes, binge eating may be triggered by episodes of hypoglycemia.
(c) Persistence of disordered behavior One-third of our sample reported highly or moderately disordered behavior at both assessments, and there was a significant tendency for disordered eating status to persist, with more than 60% of those with disordered behavior at baseline continuing to exhibit such behavior 4 years later. The behaviors present at baseline, including binge eating, self-induced vomiting, and dieting for weight loss, showed a significant tendency to persist. In addition, we found that disordered behavior tended to increase in frequency over time, which was not surprising given that our sample had moved further into the age of highest risk for eating disorders at follow-up (i.e., older adolescence and young adulthood).
ii. Screening for Disordered Behavior We demonstrated that subjects with highly disordered behavior at baseline had a threefold increase in the presence of diabetic retinopathy at 4-year follow-up compared to those with non-disordered behavior. Those who reported moderately disordered behavior also showed complications at a frequency midway between the highly and non-disordered groups, suggesting that even less frequent disordered eating and weight-loss behavior may still increase the subsequent risk of complications. We compared the value of self-report screening for disordered behavior with a diagnostic interview (the Eating Disorder Examination,51 modified by our group for diabetes) in 60 young women with diabetes from our longitudinal study.10 Among those who screened positive for one or more of the four disordered behaviors described above, there was 100% sensitivity and 74% specificity in identifying subjects who met DSM-IV criteria for an eating disorder based on the interview (kappa, 0.75, negative predictive value, 1.0, and positive predictive value, 0.68) (Unpublished data, AR,GR, MO, DD). Given the prevalence of eating disorders and their subthreshold variants in teenage girls and young adult women with type 1 diabetes, we recommend that health care professionals in diabetes clinic or office settings routinely ask specific questions about eating and weight and shape concerns. Direct questioning about dieting for weight control, binge eating, insulin omission or manipulation, laxative abuse, and self-induced vomiting should be part of regular diabetes care. Early identification of such behavior would help in detecting those with previously undiagnosed clinical or subthreshold eating disorders, and in instituting measures to prevent progression from disordered behavior to more serious clinical disorders.
iii. Impaired Metabolic Control We and others have consistently shown that eating disturbances in association with diabetes lead to significant impairments in metabolic control.7,8,10,22,23,26,27,32,42,54,63,68 In an early review of 57 case reports in which diabetes and an eating disorder were documented, Marcus and Wing69 reported that more than 75% evidenced poor metabolic control. In our longitudinal follow-up study of 91 adolescent girls and young adult women with diabetes,10 we documented the association of disordered eating and weight-loss behavior with impaired metabolic control, both at baseline and 4 years later. We found that A1C levels at baseline were significantly higher among those classified with highly disordered behavior (11.1%) than among those with moderately disordered (8.9%) or non-disordered (8.7%) behavior (P < 0.001). At follow-up 4 years later, those classified as highly or moderately disordered (9.7% and 9.6%, respectively) had significantly higher A1C levels than those in the non-disordered group (8.2%) (P = 0.005) (Figure 4).
We10 further divided our sample into groups based on good (A1C <8%), intermediate (89%), and poor (>9%) levels of control, as suggested by the DCCT findings.1 We found that 100% (n = 9) of our subjects in the highly disordered group at initial assessment had A1C levels reflecting poor metabolic control, compared to 53% of the moderately disordered group and 38% of the non-disordered group. Not surprisingly, the 14 subjects who reported persistent highly or moderately disordered behavior (i.e., at both baseline and 4-year follow-up) had persistently poor A1C levels at both times (9.5 and 9.9%, respectively). While there was little change in A1C levels over time in the 43 subjects who did not engage in disordered behavior, there was both a statistically significant and clinically meaningful improvement in A1C (mean decrease of >2%; 9.7 to 7.6%, P = 0.002) in the nine subjects who showed improved eating status at the 4-year follow-up. Also, in the 11 new cases (i.e., those reporting highly or moderately disordered behavior at follow-up, but not at baseline), there was a trend toward worsening metabolic control, although this did not reach statistical significance (Figure 5).10
In addition, in our multi-site prevalence study of eating disorders in 356 adolescent girls with type 1 diabetes,7 we found that subjects who met criteria for a DSM-IV eating disorder had significantly higher A1C levels (9.4%) than those without an eating disorder (8.6%; P = 0.04). A1C levels for subjects with a subthreshold disorder (9.1%) were intermediate between those in the DSM-IV and non-disordered groups.
iv. Short-term Diabetes-Related Complications Although the most common types of eating disorders found in this population appear to be bulimia nervosa and its less severe variants,7 there have been a number of documented cases of restricting-type disorders.8,32,38 These disorders may not present with impaired metabolic control,4 but rather with recurrent episodes of hypoglycemia precipitated by food restriction despite insulin administration.38,70 In one of our studies,10 one young woman identified with highly disordered eating at follow-up (eating disorder not otherwise specified; anorexic-type), reported 20 episodes of severe hypoglycemia in the preceding year. Other complications can include delays in normal growth and pubertal development38 and osteoporosis,75 likely due to chronic food restriction and the inadequate administration of insulin.17
v. Long-term Diabetes-Related Microvascular Complications We demonstrated the relationship between disordered eating and weight-loss behavior and microvascular complications in our 4-year follow-up study of 91 adolescent girls with type 1 diabetes.10 These girls were 1218 years of age at baseline, with a mean duration of diabetes of 8 years. A subset of our group at 4-year follow-up underwent a series of medical evaluations, including eye examinations and seven-field stereoscopic color fundus photography to detect diabetic retinopathy and 1- and 24-h urine collections to evaluate urinary albumin excretion rates, an indicator of early diabetic nephropathy. The most striking finding was that some degree of diabetic retinopathy (mild background retinopathy or worse) was present at follow-up in 86% of young women with highly disordered eating at baseline, compared to 43% with moderately disordered eating and 24% with non-disordered eating (P = 0.004; Figure 6).
Furthermore, disordered eating status accounted for more of the explained variance in predicting the presence of retinopathy at follow-up than did duration of diabetes, a well-established risk factor for the onset of microvascular complications.1 Although there was a trend in our data toward more abnormal urinary albumin excretion results among individuals with highly disordered eating at baseline, the mean duration of diabetes at follow-up (11 years) may not have been not long enough for incipient nephropathy to occur in sufficient numbers to be able to show a statistically significant association with disordered eating status (Figure 6). Others have reported a similar relationship between eating disorders and microvascular complications in smaller studies of young women with type 1 diabetes, including case reports8,32,69 and small cross-sectional and case-controlled studies.9,11,47,48,75,76 Only one study56 failed to find a significant association between eating disorder status or insulin omission and microvascular complications. In an uncontrolled study, Steel et al.8 found microvascular complications in 11 of 15 subjects (73%), aged 1625 years with clinically apparent eating disorders (12 anorexia nervosa, 3 bulimia nervosa). The mean duration of diabetes in this group was 12.5 years, and the mean glycated hemoglobin level was 14.8% (range 1118%). Sixty percent of their subjects identified with an eating disorder reported reducing insulin to control weight, and 67% reported bingeing and vomiting. Eleven of the 15 subjects had developed retinopathy, 6 had nephropathy as evidenced by persistent proteinuria, and 6 had peripheral neuropathy (4 with acute painful polyneuropathy). Although only those subjects with clinically apparent eating disorders were assessed, it was noted that only four of their 15 eating disordered subjects were free of microvascular complications. Two of the 4 subjects had only had diabetes for 16 years, suggesting that they may not have had diabetes long enough for clinical complications to become apparent. Colas et al.9 reported more severe retinal lesions and an earlier onset in 29 patients with type 1 diabetes and an eating disorder (9 anorexia nervosa plus bulimia, 20 bulimia nervosa alone) compared to similar patients with diabetes who were matched for age, duration of diabetes, and age of onset of diabetes. The mean age of the eating disorder subjects was 26 years, and their mean duration of diabetes was 9 years. Those in the eating disorder group had higher A1C levels compared to the control group (10.8 vs. 8.1%, respectively), more retinal lesions (62 vs. 20%), and autonomic neuropathy (10 vs. 0%). Polonsky et al.11 surveyed 341 women aged 1360 years (mean age 33 years) with type 1 diabetes (mean diabetes duration 15 years) to detect the presence of intentional insulin omission and its association with disordered eating attitudes and behavior, metabolic control, and long-term complications. Overall, 30% of this sample reported intentional insulin omission, with 8.8% reporting frequent omission, although only 13.5% admitted that this behavior was for weight-related reasons. In this study, insulin omission was not limited to the younger women, with 40% of 15- to 30-year-olds (16% reporting frequent omission), 30% of 31- to 45-year-olds, and 20% of 46- to 60-year-olds admitting to this behavior. Compared to non-insulin omitters, those omitting insulin for any reason reported more disordered eating, poorer glycemic control, more frequent diabetes-related hospitalizations, and higher rates of retinopathy (65 vs. 50%) and nephropathy (34 vs. 17%). Ward et al.75 presented findings from a retrospective review of a series of 17 of 21 subjects aged 2146 years (median age 27 years) with diabetes, presenting to a hospital-based eating disorder unit over a 4-year period. Diabetes-related complications were reported in 11 (65%) of the 17 patients, including 7 with retinopathy (4 requiring laser treatment), 6 with peripheral neuropathy, and 1 with necrobiosis lipoidica. Of the five women who underwent bone densitometry, all had osteoporosis. Cantwell and Steel47 surveyed 147 women with diabetes aged 1732 years and compared the 22 high scorers on the self-report Eating Attitudes Test77 to the 26 low scorers. This comparison revealed that high scorers (i.e., reflecting more disordered eating attitudes) misused insulin more frequently than low scorers (36 vs. 8%), and more had evidence of retinopathy (46 vs. 15%) and nephropathy (31 vs. 6%). Takii et al.76 compared a cohort of young women aged 1636 years with type 1 diabetes who had been referred for eating disorder treatment (22 bulimia nervosa, 11 binge eating disorder [BED]) with 32 subjects with diabetes but without an eating disorder. They found significantly poorer metabolic control in those with an eating disorder compared to those without (average A1C levels were 12.3% in those with bulimia nervosa, 9.7% in BED subjects, and 6.2% in the non-eating disordered group). They also found that retinopathy and nephropathy were significantly more common among subjects with bulimia nervosa (41 and 46%, respectively) compared to those with BED (0 and 9%, respectively) and those in the non-disordered group (6 and 6.3%, respectively). There is only one report in which diabetes-related complications were not associated with eating disturbances or disordered behavior. In an 8-year follow-up of 33 young women with type 1 diabetes (aged 1118 years at initial assessment; mean age 15 years), Bryden et al.56 reported that 46% of their subjects who developed complications omitted insulin for weight control. However, they did not find a statistically significant relationship between either disordered eating at baseline or insulin misuse and the onset of diabetes-related complications.
Conclusions
Primary contributor: Sherry Maharaj, PhD
In Brief A growing body of evidence has identified family functioning as a significant correlate of diabetes-related outcomes among teens with diabetes, as well as a potential risk factor for eating disorders in non-diabetic females. Problems with metabolic control and treatment compliance among teens with diabetes have been found in association with family environments characterized by high conflict and low cohesion, inadequate family structure and organization, impaired communication and problem-solving skills, and negative relationships defined by criticism and perceived rejection.7885 Similar patterns of family disturbance have been identified in association with eating disorders in non-diabetic females. The families of young women with bulimia nervosa have been found to demonstrate a pattern of hostile, disengaged, and less nurturing behaviors that negate the girls emotional needs.8688 Although research has consistently linked family dysfunction with eating disorders among non-diabetic females, as well as with the adequacy of diabetes management among teens with diabetes, there has been little systematic investigation into the relationship between family functioning, eating disorders, and diabetes-related outcomes. The etiology of eating disorders is multi-determined, likely arising from a complex interplay of biological, psychological, and sociocultural factors.89,90 Families have been shown to have a significant influence on adolescents overall psychosocial adaptation, as well as their adjustment to a chronic medical illness.91,92 The family environment plays a primary role in the emergence and differentiation of an adolescents self-concept. Family communications that support and validate teenagers experiences and perspective are key to promoting the emergence of their self-identity93,94 and facilitating the process of individuation. The latter is considered to be the primary developmental challenge of adolescence.93,95 Both clinical observation and theory have linked eating disorders in non-diabetic females to disturbances in the mother-child relationship, characterized by misattunement to the girls emotional needs and failure to respond empathically to child-initiated cues.9698 Failure to respond appropriately to a childs subjective experience may interfere with her ability to develop a separate and integrated sense of self and impair her capacity for individuation.96,98,99 Similarly, it has been suggested that a chronic medical illness such as diabetes may interfere with successful individuation among adolescents.100,101 Diabetes self-care involves a complex, multi-component treatment plan that poses difficulties for many teens102 and invariably requires a shared family effort.103 A chronic illness such as diabetes may increase adolescents dependence on family members at the very time they are struggling to achieve greater independence.104 This dependence, coupled with parental anxieties about the illness, may heighten normal conflict in the negotiation of autonomy.105 The added demands of diabetes may not only complicate the developmental challenges of adolescence,106 but also strain the adaptive resources of vulnerable individuals and their families and lower the threshold for the expression of psychiatric disturbance.83,107 A review of the literature during the past 15 years on the association between the family environment, eating disturbances, and diabetes outcomes among adolescent girls with type 1 diabetes revealed only three reports based on a cross-sectional study conducted by our research group.1315 Participants in the study included 113 girls with type 1 diabetes for at least 1 year [mean ± SD age = 15 ± 2.2 years; diabetes duration = 7 ± 3.7 years; hemoglobin A1c [A1C] = 9 ± 1.4 %)], attending the Diabetes Clinic at the Hospital for Sick Children in Toronto, and their mothers [mean age = 44 ± 5.5 years]. Girls were classified as non-eating disturbed (n = 56), mildly disturbed (n = 37), or highly eating disturbed (n = 20), based on their self-reported disturbances in eating attitudes and behavior. Our major study findings will be reviewed here in terms of the quality of family functioning; the role of eating disturbances as a moderator of the impact of the family environment on metabolic control; and maternal weight and shape concerns.
i. Quality of Family Functioning
In addition, eating disturbed girls and their mothers described their overall family environments as more conflicted, with less personal support and inadequate organization and structure in the planning of activities and responsibilities. While these families are perceived to provide inadequate support and structure, they simultaneously emphasize high levels of achievement and behavioral independence.13 These self-reported disturbances in family relationships were corroborated by videotaped observations of mother-daughter interaction patterns among diabetic girls with and without eating disturbances.15 Eighty-eight mothers and daughters from our sample of 113 participants were videotaped engaging in two, 7-minute problem-solving tasks (one was diabetes-related, the other was a general parent-teen dilemma). The quality of mother-daughter interactions was rated using the Autonomy and Intimacy Rating System (AIRS),108 which rates mothers and daughters communication patterns on 15 dimensions that reflect the ways in which autonomy (i.e., the experience of oneself as separate) and intimacy (i.e., the sense of relatedness to others) are negotiated in these relationships. Our findings demonstrated that eating disturbances in girls with diabetes are associated with observed impairments in mother-daughter interactions that constrain both the teens emerging sense of autonomy and emotional closeness in these relationships. Compared to mothers and non-eating disturbed daughters, interactions between mothers and eating disturbed girls were characterized by a negative mood and feeling tone with low levels of emotional attunement and genuine empathic support and misattunement around diabetes-related needs. These mothers and daughters exhibited limited perspective-taking abilities, used defensive communications that escalated conflict, and engaged in communication styles that tended to limit the teens expression of thoughts and feelings. Girls with eating disturbances demonstrated greater difficulties expressing themselves as separate, often exhibiting periods of withdrawal, confusion, or childish assertions (e.g., "I can take my insulin when I want, its my life!"). While their mothers encouraged the teens increasing independence around diabetes self-care, they failed to provide appropriate parental support (e.g., "I am not going to re-arrange my whole schedule when you should be the responsible one!"). While these interactional difficulties were found during the discussion of both problem-solving tasks, they were more pronounced during conversations about diabetes-related issues (Figure 8).
Optimal parental responsiveness to normal adolescent strivings for autonomy requires a balance between fostering independence and providing parental support.93 For teenagers with diabetes, achieving this balance may be more difficult because the successful management of diabetes requires increasing parental involvement. Our research findings suggest that families of girls with diabetes and eating disturbances may be less able to appropriately balance the teens simultaneous needs for independence and supportive guidance. These girls tend to live in family environments that are perceived to emphasize high levels of behavioral independence and achievement, while providing inadequate levels of personal support, structure, and organization. Findings also suggest that these girls are not adequately supported in their efforts to develop independent thinking and self-determination in interactions with their mothers, nor are they provided with a supportive parental base from which to explore and validate their identity. These deficiencies may heighten feelings of helplessness and ineffectiveness among these girls and interfere with the development of an integrated, separate sense of self. Efforts to gain self-mastery and to bolster self-esteem through weight and shape control may be a consequence.
ii. Eating Disturbances, Family Functioning, and Metabolic Control Our group has demonstrated that the impact of family interaction patterns on metabolic control is moderated by the presence and severity of an eating disturbance in girls with diabetes.13 Among girls with no eating disturbances, we found that optimal metabolic control is associated with less rigidly controlled family environments that promote the open expression of thoughts and feelings. In contrast, good metabolic control among girls with more highly disturbed eating behavior is associated with family environments that are less affectively charged and more controlled and ordered (i.e., higher family control with less emphasis on behavioral independence). Thus, families of girls with diabetes must walk a precarious line between fostering adolescent autonomy and simultaneously providing supportive guidance appropriate to the needs of the individual girl.
iii. Maternal Weight and Shape Concerns Research in non-diabetic populations has demonstrated a significant association between problematic eating attitudes and weight-loss behavior in mothers and heightened body dissatisfaction, disordered eating, and weight-loss attempts in their daughters.111114 We have shown for the first time that eating disturbances in girls with diabetes are significantly associated with heightened weight and shape concerns in their mothers.14 Mothers of girls with eating disturbances reported more dissatisfaction with their own weight and were more likely to be on a diet, engage in binge eating, and exercise for weight-control purposes (Figure 9). Furthermore, maternal disturbances in eating and weight-control behavior were found to be a significant and independent predictor of eating disturbances in adolescent girls with diabetes.
Implications of Family-Based Research Findings Our study findings suggest that the family environment may enhance the risk for eating disturbances in girls with diabetes through two interrelated pathways: first, through family interaction patterns that fail to support the teens complementary needs for independence and supportive guidance; and second, through modeling and reinforcing the value of thinness for the female identity. Furthermore, the familys impact on diabetes-related outcomes, such as metabolic control, is moderated by the presence and severity of eating disturbances in these girls. We conclude from our findings that standard interventions designed to improve metabolic control, such as intensive diabetes management, are unlikely to be effective as long as eating disturbances and problematic family interactions persist. Effective treatment of girls with chronically poor diabetes control requires routine assessment of the presence of eating disturbances, as well as attention to goodness of fit between the characteristics of the family and the needs of the specific child. Specifically tailored family-based therapeutic interventions are needed to improve disturbed family interaction patterns that may heighten the risk for eating disturbances and poor diabetes outcomes among girls with diabetes. For example, families that fail to provide the necessary structure, order, and control may contribute to feelings of helplessness among girls with more problematic eating disturbances and place these vulnerable teens at risk for poor diabetes management. In such situations, treatment should include fostering appropriate structure and limit-setting within the family as a necessary concomitant of diabetes management. In addition, these mothers and daughters may benefit from learning to communicate in a manner that recognizes and supports individual differences while maintaining continued emotional closeness. In contrast, support for non-eating disturbed girls includes fostering a family environment without rigid rules and procedures and enhancing family support of the teenagers development of self-expression and self-mastery in managing their diabetes and other age-appropriate tasks. Health professionals should also assist families in de-emphasizing the focus on appearance and thinness and facilitate parental support of their daughters emerging self-mastery and self-esteem in multiple domains beyond weight and shape.
Primary contributor: Marion Olmsted, PhD
In Brief There is an extensive literature on the treatment of eating disorders, and comprehensive practice guidelines have been published by the American Psychiatric Association.115 Recommended treatments include cognitive-behavioral therapy (CBT), | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||