PREDICTORS OF 1-YEAR TREATMENT OUTCOME IN BULIMIA-NERVOSA

We examined predictors of outcome 1 year after completion of a randomi zed clinical trial assessing the additive efficacy of two forms of exp osure with response prevention to a core of cognitive-behavioral thera py (CBT) for bulimia nervosa (BN). One hundred one women who met DSM-I II-R criteria for BN, and who completed the clinical trial, were avail able for follow-up at 1 year. Predictor variables were assessed prospe ctively and partitioned temporally to reflect lifetime history (includ ing personality), pretreatment clinical status, and posttreatment clin ical status. Outcome was based on the frequency of binging and purging in the 3 months before assessment based on carefully constructed life chart interviews. A series of stepwise logistic regressions were perfo rmed to determine independent predictors of 1-year outcome while contr olling for treatment received. Demographic variables were unrelated to treatment outcome. A history of obesity was predictive of poor outcom e, whereas a history of alcohol dependence decreased the odds of poor outcome, High self-directedness on the Temperament and Character Inven tory (TCI) predicted favorable outcome at 1 year, whereas personality disorder symptoms were not predictive. Pretreatment global functioning , bulimia scores on the Eating Disorders Inventory (EDI), and the pres ence of major depression predicted poor outcome. Posttreatment binging , food restriction, and urges to binge on a cue reactivity assessment predicted poor outcome at 1 year. The character trait of self-directed ness is a strong predictor of good outcome for CBT, and methods to enh ance this trait may be worthy of investigation. Low global functioning and the presence of major depression at presentation may require addi tional treatment than focused CBT for BN. Our results argue for treatm ent goals that include abstinence from binging and restricting and dec reases in urges to binge in response to high-risk cues. Copyright (C) 1998 by W.B. Saunders Company.