Lifetime patterns of comorbidity in eating disorders: An approach using sequence analysis

Objective: Eating disorders (EDs) have high rates of psychiatric comorbidity. This study aimed to characterize longitudinal patterns of comorbidities in adults with EDs. Methods: Sequence analysis and hierarchical clustering were applied to ages of onset and recency for select eating, substance, mood, and anxiety disorders from the 479 participants in the Collaborative Psychiatric Epidemiology Surveys with lifetime DSM-IV bulimia nervosa, binge eating disorder, or anorexia nervosa. External validators were compared across clusters using chi-square tests. Results: Five clusters were identified among individuals with any lifetime ED based on longitudinal sequence of psychiatric disorder onset and remission, characterized as: (1) multi-comorbid with early onset of comorbid disorder (46%); (2) moderate preeminent anxiety with moderate comorbidity and low ED persistence (20%); (3) late ED onset with low comorbidity (15%); (4) early onset, persistent ED with low comorbidity (14%); and (5) chronic, early onset depression (5%). Clusters were well differentiated by significant differences in age, body mass index, race, and psychiatric indicators. Conclusions: This study demonstrates a new method to assess clustering of comorbidity among individuals with lifetime EDs. Having a psychiatric diagnosis prior to an ED was associated with greater psychopathology and illness duration. Information on timing of diagnoses may allow for more refined comorbidity classification.