Inhibitory Control Training for Binge-Spectrum Eating Disorders

We recruited adults with clinically significant binge-spectrum EDs (N = 63), including BN-spectrum and BED, from the community for participation in a parent trial of CBT-E augmented by inhibitory control training (clinicaltrials.gov identifier: NCT04076553). Participants were included in the parent trial if they were between 18 and 55 years old, experienced an average of at least one objective binge eating episode per week over the previous 12 weeks, had stable psychiatric medication for the past 3 months (if applicable), had a reliable Internet connection, and were located in the USA and willing and able to participate in remote intervention and assessments. Participants were excluded if they were not fluent in English, were below a BMI of 18.5, were planning to begin (in the next 6 months) or currently participating in another weight loss treatment or psychotherapy for binge eating and/or weight loss. Participants were not eligible if they had a diagnosis of autism spectrum disorder or intellectual disability, were currently experiencing other severe psychopathology that would limit their ability to engage in the treatment program (e.g., severe depression, substance dependence, active psychotic disorder), or demonstrated high levels of inhibitory control (and thus would not benefit from the inhibitory control training portion of the treatment). Participants were also excluded from the parent trial if at least half of their binge episodes were composed nearly entirely of fruit/vegetables (i.e., 80% or more of the total food consumed during binges were raw fruits and vegetables) because of the intention to test inhibitory control training toward more traditional binge foods (e.g., pizza, ice cream). Participants were not eligible if they had experienced a recent head trauma, neurological condition, or brain condition that would interfere with completion of daily computer trainings.
The current study represents a secondary analysis of data from the parent trial. For the current study’s analyses, participants were included if they completed at least one session of treatment. Of these 63 individuals, 11 (17.5% of sample) dropped out of treatment prior to completing all 12 sessions. Attrition rates in our study are comparable to rates in other trials of CBT for EDs [3 (link)]. Participants completed 10.48 treatment sessions on average (SD = 3.51). In the current sample, 29 participants were randomized to the “sham” training condition, and 34 to the inhibitory control training condition. Table 1 depicts participant demographic information, diagnoses, and BMI.Table 1

Participant demographics and baseline characteristics by diagnosis (N = 63)

	Bulimia nervosa (incl. subthreshold; n = 27)		Binge eating disorder (n = 36)
	Mean or n	SD or %	Mean or n	SD or %
Age	37.2	12.7	42.9	9.6
Gender
Male	1	3.7%	6	16.7
Female	26	96.3%	30	83.3
Race
White	21	77.8%	31	86.1%
African American	2	7.4%	4	11.1%
Asian	2	7.4%	0	0%
Multiracial	1	3.7%	1	2.8%
Unknown/prefer not to say	1	3.7%	0	0%
Ethnicity
Hispanic/Latinx	4	14.8%	3	8.3%
Non-Hispanic	23	85.2%	33	91.7%
Disordered eating behaviors
Binge episodes past 3 months	91.4	58.9	91.3	48.6
Compensatory behaviors 3 months	71.7	77.3	0.5	1.4
BMI	31.3	8.3	36.2	12.6
Fear of weight gain
GFFS 10-item scores	30.9	5.7	23.8	7.4

BMI body mass index, GFFS Goldfarb Fear of Fat Scale