علائم خود تصویر و اختلال تغذیه ای در نوجوانان عادی و بالینی

Eating disorders (ED) are psychiatric disorders of multifactorial origin, predominantly appearing in adolescence. Negative self-image is identified as risk factor, but the association between self-image and ED in adolescents or sex differences regarding such associations remains unclear. The study aimed to investigate the relationship between specific self-image aspects and ED symptoms in normal and clinical adolescents, including sex differences. Participants included 855 ED patients (girls = 813, boys = 42) and 482 normal adolescents (girls = 238, boys = 244), 13–15 years. Stepwise regression demonstrated strong associations between self-image and ED in normal adolescents (girls: R2 = .31, boys: R2 = .08), and stronger associations in patients (girls: R2 = .64, boys: R2 = .69). Qualitative sex differences were observed in patients. Connections between specific self-image aspects and ED have implications for clinical management of ED. The strong link between self-image variables and ED symptoms in normal girls, but not boys, is discussed in terms of the continuity–discontinuity hypothesis.

Adolescence is a critical developmental period involving identity formation, physical, cognitive, social and sexual development, and increased self-awareness. Although the majority of adolescents make this transition without significant difficulties, some encounter psychological and behavioral problems with more lasting effects (Bongers et al., 2003 and Ybrandt, 2007). Eating disorders (ED) are one such problem area, predominantly found in females, usually appearing in adolescence and often with a chronic course. The female-to-male ratio of any ED changes from about 4:1 during adolescence to about 10:1 in adulthood (Reijonen et al., 2003 and Striegel-Moore and Bulik, 2007), and a Norwegian study on 14 to 15 year-olds (Kjelsås, Børnstrøm, & Götestam, 2004) found total ED point prevalence rates of 7.6% among girls (counting anorexia nervosa, AN; bulimia nervosa, BN; and eating disorders not otherwise specified, EDNOS) and 2.2% among boys. Many more have sub-clinical symptoms, hence at risk for developing ED. Early detection and treatment of ED improve the chances for a better outcome (Berkman, Lohr, & Bulik, 2007), making research on risk factors and their relationship to normal-spectrum psychological variables important (Fichter, Quadflieg, & Hedlund, 2006). Besides being a young female and dieting, poor self-esteem has been identified as an important risk factor for ED (Fairburn et al., 1999, Fairburn et al., 2003 and Ghaderi and Scott, 2001). Cervera et al. (2003) found that high self-esteem protected from ED, while low self-esteem was related to subsequent development of ED in a sample of women aged 12–21. Patients with ED have in general lower self-esteem than normal controls (Ghaderi and Scott, 2001 and Sassaroli et al., 2008). However, there is insufficient evidence for positive effects of prevention programs targeting self-esteem (Pratt and Woolfenden, 2008 and Stice et al., 2007). One possible reason for this is that self-esteem as a concept is too global and undifferentiated, hence unable to capture all aspects of a person's self-image potentially important when developing ED. Rosenberg (1989) defines self-esteem as overall appraisal of self-worth; how much one values oneself. As a construct, the self might however be defined as a set of cognitions, knowledge, and opinions about the self, with a descriptive component of both internal and external attributes (self-concept), an evaluative component of both general personal worth (self-esteem), and own competencies and coping resources (self-confidence), as well as self-regulation strategies. Usually in research, one aspect is in focus at the time, most often self-esteem. One model that incorporates both self-image as a two-dimensional construct and theoretical implications for interpersonal behavior is the Structural Analysis of Social Behavior (SASB, Benjamin, 1974 and Benjamin, 2000). It is based on interpersonal- and attachment theory and self-image is seen as a product of interpersonal interactions (Benjamin, 1993), continuously affecting social behavior (Henry, 1994). The SASB model is circumplex with two dimensions: Affiliation (Self-love to Self-hate) and Autonomy (Self-control to Self-freeing), and the theory describes how these relate to corresponding interpersonal behaviors. Fig. 1 shows the Introject surface of the model with the above-mentioned dimensions represented on two axes (Affiliation horizontally and Autonomy vertically). Points along the perimeter illustrate combinations of the underlying dimensions and divide into eight clusters. Full-size image (27 K) Fig. 1. The SASB Introject cluster model. The model displays the eight clusters and the two axes (Affiliation and Autonomy). From: Benjamin, L.S. (1996). Interpersonal diagnosis and treatment of personality disorders, 2nd Ed. N.Y.: The Guilford Press. © The Guilford Press. Figure options The affiliation dimension conceptually approximates self-esteem (Pincus, Gurtman, & Ruiz, 1998). SASB has been used previously in ED research (Birgegård et al., 2009, Björck et al., 2003, Björck et al., 2007, Björk et al., 2009, Humphrey, 1989, Pincus et al., 1998 and Ratti et al., 1996). More specifically, SASB self-image improves more in patients completing treatment compared to patients who drop out (Björk et al., 2009). Self-image successfully distinguishes between treatment dropouts and completers and predicts dropout (Björck et al., 2007). Furthermore, ED patients present with distinct interpersonal profiles significantly more negative than controls (Björck et al., 2003); high levels of self-hate increase the risk of poor outcome in ED (Björck et al., 2007), and different aspects of self-image predict outcome in BN and AN (Birgegård et al., 2009). In this research however, adult populations have been in focus. Little research has investigated whether the sex difference in ED prevalence is accompanied by psychological differences. Some gender differences in ED have been noted: Geist, Heinmaa, Katzman, and Stephens (1999) found that females scored higher than males on drive for thinness and body dissatisfaction, Lewinsohn, Seeley, Moerk, and Striegel-Moore (2002) showed that women were more likely than men to seek treatment despite being at comparable levels of problematic eating behaviors; Støving, Andries, Brixen, Bilenberg, and Hørder (2011) found that illness duration among patients with AN was shorter for males (3 years) than for females (7 years). Their results also suggested better outcome for males. In normal samples, gender difference in self-esteem is a fairly robust finding (Feingold, 1994 and Hall, 1984), with boys reporting higher self-esteem than girls during adolescence (Frost and McKelvie, 2004 and Mäkinen et al., 2012). With regard to gender differences in self-image as measured by SASB, little has been reported. In the only SASB study of gender differences, antisocial adolescent girls reported a more negative self-image than a corresponding subsample of boys. No such differences were found in a normal comparison group (Östgård-Ybrandt & Armelius, 2004). Nothing has yet been reported about gender differences in the association between self-image and ED in normal or clinical groups. We aimed to identify associations between ED symptoms and distinct aspects of self-image in adolescents, and to compare these associations in a clinical sample versus a non-clinical sample, and in boys versus girls. While for example the importance of general self-esteem for ED has been investigated previously, we wanted to expand on this body of research using a more multi-faceted self-image operationalization. Higher precision regarding self-image factors related to ED detected before ED symptoms is fully established, may inform and improve both prevention programs and ED treatments. Contrasting normal and clinical samples may further our understanding of psychological variables in ED.