Cognitive Behavioral Therapy and Lisdexamfetamine, Alone and Combined, for Binge-Eating Disorder With Obesity: A Randomized Controlled Trial

Binge-eating disorder (BED) is a prevalent, costly public health problem associated with serious functional impairments and heightened rates of psychiatric and medical comorbidities. Few evidence-based treatments are currently available for BED. We tested the effectiveness of cognitive-behavioral therapy (CBT), lisdexamfetamine (LDX), and combined CBT+LDX, for BED comorbid with obesity. Randomized controlled trial was conducted March 2019 to September 2023 at a single site. N=141 patients with BED (83.7% women, mean age 43.6, mean BMI 38.6 kg/m2) were randomized to one of three 12-week treatments: CBT (N=47), LDX (N=47), or CBT+LDX (N=47); 87.2% completed independent posttreatment assessments. Mixed models revealed binge-eating frequency decreased significantly in all treatments, with CBT+LDX having the largest reduction and significantly outperforming CBT and LDX, which did not differ. Intention-to-treat binge-eating remission rates differed significantly between treatments, with CBT+LDX having the highest remission rate (70.2%) followed by CBT (44.7%) and LDX (40.4%). Mixed models revealed percent weight loss increased significantly throughout treatment with LDX and CBT+LDX but remained unchanged in CBT. LDX and CBT+LDX had significantly greater percent weight loss than CBT starting after one month and through posttreatment. Intention-to-treat rates of attaining ≥5% weight loss differed across treatments, with LDX having the highest (53.2%), followed by CBT+LDX (42.6%) and CBT (4.3%). Analyses revealed significant reductions in eating-disorder psychopathology; CBT+LDX had largest reductions and significantly outperformed CBT and LDX. CBT, LDX, and CBT+LDX showed significant improvements in BED, with a consistent pattern of the combined CBT+LDX being superior to the two individual treatments, which differed little.