An empirical study of the classification of eating disorders

Objective: The nosology for eating disorders, despite having been extensive ly revised over time, may not capture the natural clustering of eating-rela ted pathology as it occurs in general population samples. Method: Detailed information about anorectic and bulimic behaviors was asse ssed through personal interviews of 2.163 Caucasian female twins from a pop ulation-based registry. Latent class analysis was applied to nine eating di sorder symptoms to develop an empirically based topology. Demographic, como rbidity, personality, and co-twin diagnosis data were used to validate the resultant classes. Results: A six-class solution provided the best fit. One class displayed di storted eating attitudes without low body weight. Two classes demonstrated low weight without the psychological features of eating disorders. Three cl asses broadly resembled the DSM-IV classifications of anorexia nervosa, bul imia nervosa, and binge-eating disorder. For all classes, and especially fo r the three that reflected current diagnoses of eating disorders, monozygot ic twins resembled one another much more in terms of class membership than did dizygotic twins. Conclusions: The authors found within a community sample, and through an em pirical method, classes of eating-related pathology that broadly resembled the current classifications of anorexia nervosa, bulimia nervosa, and binge -eating disorder. Additional classes were marked by either the psychologica l features of eating disorders or low body weight. Individuals in the three eating-disorder classes had similar personality profiles but displayed dif ferences in symptom expression and co-twin risk fur anorexia nervosa, bulim ia nervosa, and obesity.