Subtype criteria for bulimia nervosa: short- versus long-term compensatory behaviors

Weight control methods used by a group of bulimic patients were studied, analyzing the relationship among compensatory strategies and other clinical variables. Sixty-nine female consecutive patients who sought help for DSM-IV bulimia nervosa were recruited for the study. The prevalence and frequency of use of binge eating and six compensatory methods (vomiting, laxatives, diuretics, diet pills, fasting, and compulsive exercise) were assessed in each patient. Factor analysis was used to group the variables, and a cluster analysis was performed on a second step. The clinical variables were finally analyzed in each of the groups isolated through cluster analysis. According to the results of the factor analysis, the compensatory strategies were identified as short-term compensatory methods (vomiting), long-term methods (diet pills, diuretics, and laxatives), and nonpurging methods (dieting and exercise). Three groups of patients were isolated through cluster analysis: short-term purgers (vomiting), long-term purgers (laxatives + diet pills + diuretics), and a mixed group (vomiting + laxatives). Long-term purgers were older and heavier, had a greater prevalence of past overweight, and used more compensatory methods. These results confirm the necessity to continue investigating alternative ways of classifying bulimia nervosa patients based on compensatory behaviors, considering the existence of clinical dimensions rather than rigid clinical subtypes.