Eating Disorders in Adolescence: When Should Prevention Occur?

Abstract

Disordered eating behaviors can have severe effects on medical, psychological, and social functioning (1,2), making these behaviors an important focus of multidisciplinary attention. The median age of onset of eating disorders across the population ranges from 18 to 21 years, depending on the condition, with the earliest age of onset at 10 years for anorexia nervosa and 15 years for other disorders (3). Subthreshold eating disorders, which are conditions that involve disordered eating but do not meet full criteria for an eating disorder, are common and frequently associated with increased levels of impairment (2,4). Recent data indicate that in adolescents age 13 to 18 with eating disorders, median age of onset ranges from 12.3 to 12.6 years across disorders (2). Treatment of these conditions is known to be challenging (5). These data, together with the observation that the presence of maladaptive eating attitudes and behaviors in adolescence has been linked to the subsequent development of eating disorders (6), underscore the importance of effective interventions to prevent and treat maladaptive eating patterns and eating disorders in adolescents. Longitudinal studies, such as the study presented in this issue of the Journal of the American Dietetic Association by Neumark-Sztainer and colleagues (7), that describe patterns of symptoms over time move the field an important step closer to developing effective prevention strategies by providing information about the appropriate population, timing, and content of prevention efforts. Neumark-Sztainer and colleagues (7) report on a 10-year longitudinal study of the prevalence of weight control and eating behaviors from early adolescence through middle young adulthood. Study participants included males (n1,030) and females (n1,257) in early adolescence (30% of sample; mean age 12.80.7 years) or middle adolescence (70% of sample; mean age 15.90.8 years) at baseline and in early to middle young adulthood at followup. Participants completed surveys at baseline (19981999) and at 10-year follow-up (2008-2009). A 48.2% follow-up response rate was attained, and data used in the study analyses were weighted to account for differences in attrition across demographic variables. The study sample was well-distributed across sex, ethnicity, and socioeconomic status. Specific weight-control and eating behaviors that were assessed included dieting, unhealthy and extreme weight-control behaviors, and binge-eating with loss of control. Trends in the prevalence of behaviors across time and intra-individual tracking of behaviors were explored. Results of the study suggest that the prevalence of dieting and unhealthy weight-control behaviors (eg, fasting, skipping meals, etc) remained fairly consistent over time across age and sexes, with the exception of increases in dieting among older males and decreases in unhealthy weight-control behaviors among older females. Extreme weight-control behaviors (ie, using diet pills/laxatives/ diuretics or vomiting) and binge-eating with loss of control, the less prevalent but arguably most concerning behaviors that were assessed given that these behaviors are part of the diagnostic criteria for clinical eating disorders, increased significantly across nearly all age groups and sexes, particularly among older adolescents. Increases in diet-pill use in all groups are particularly concerning given that long-term results of such medications are not completely clear, and pharmacotherapy for weight loss in adolescents is recommended only in rare cases (8,9). Intra-individual tracking analyses indicated that adolescents endorsing dieting and unhealthy weightcontrol behaviors were significantly more likely to continue endorsing such behaviors into young adulthood, across ages and sexes. This pattern was also found for extreme weight-control behaviors and binge-eating with loss of control, although almost exclusively among the older groups of male and female adolescents. The prevalence and continuity of disordered eating behaviors found in this study highlight the need to identify and develop prevention and intervention programs for adolescents to help curtail distressing and potentially dangerous symptoms in a timely way.