Objective: Few studies have examined the characteristics of atypical restrictive anorexia nervosa (AN) with a well-powered design. The study aims to explore this issue, with particular attention paid to psychopathology and response to outpatient treatment.
Method: The sample consists of 365 participants with restrictive AN and 204 with atypical AN. Three types of atypical AN were included: subthreshold (all the criteria except weight); partial (AN without amenorrhea); and participants with AN without fear of gaining weight.
Results: Participants with AN without fear of weight gain reported the lowest lifetime BMI and subthreshold AN the highest. Participant with partial AN reported the highest levels of psychiatric symptoms and novelty seeking. All types of atypical AN showed high rates of dropout, whereas participants with subthreshold AN showed the highest level of full remission after treatment.
Discussion: Before considering a revision of the diagnostic criteria of AN, further studies on adequately large samples are needed.