Weight suppression as a predictor variable in the treatment of eating disorders: A systematic review.

WHAT IS KNOWN ON THE SUBJECT?: Weight suppression (WS) has been suggested to predict outcome following psychological treatment for an eating disorder (ED). Some findings are contradictory and have not been considered systematically. WHAT THE PAPER ADDS TO EXISTING KNOWLEDGE?: The review suggests that weight gain at post-treatment is reliably predicted by pretreatment WS, but findings regarding other outcomes (e.g., treatment dropout) are less consistent. Approximate effect sizes for observed relationships are identified, alongside support for biobehavioural theories of metabolic adaptation to weight loss. WHAT ARE THE IMPLICATIONS FOR PRACTICE?: Degree of WS at pretreatment is associated with weight gain and is important for clinicians to consider before offering treatment to patients with EDs. Patients high in WS might benefit from further support (e.g., psychoeducation) prior to beginning treatment. ABSTRACT: Introduction Weight suppression (WS-the difference between highest body weight and current body weight) has been proposed as a predictor of treatment outcome within eating disorders (EDs), although this hypothesis has not been consistently supported. Aim/Question Review the association between pretreatment WS and outcome following psychological treatment for EDs. Method A comprehensive electronic database search for published and unpublished literature from 1979 to 2017. Reference lists were also inspected. Eligibility criteria were determined according to relevant guidelines and a quality appraisal was conducted. Results Twelve studies met inclusion criteria (one was subsequently excluded based on insufficient data). Greater WS was generally associated with weight gain at post-treatment although not with other treatment outcomes. Discussion The existing evidence, with data from 1,566 participants, is summarized according to three main post-treatment outcomes: weight change; treatment completion; and symptom abstinence. Patients with disordered eating and greater WS may need to gain more weight than others during treatment to achieve good outcomes. Recommendations for future studies are provided. Implications for practice Evidence-based treatments for EDs may benefit from considering WS when planning treatment, such as further psychoeducation on weight changes. Societal interventions regarding promotion of healthy eating may also draw on these findings.

Who benefits most from guided self-help for binge eating? An investigation into the clinical features of completers and non-completers.

Guided self-help (GSH) is a recommended first step in treatment for bulimia nervosa (BN) and binge eating disorder (BED) (NICE, 2004). It remains unclear what makes some individuals more likely to respond to this form of treatment than others. Forty-eight patients participated in this study using a GSH programme for binge eating. Profiles of treatment completers and non-completers are compared, and reasons for non-completion explored. Completion of treatment was associated with significant improvements in mood, general functioning and on measures of dietary restraint, frequency of objective binge eating (OBE), laxative misuse, self-induced vomiting (SIV) and driven exercise. Improvements were maintained at follow-up. Treatment non-completers reported significantly higher pre-treatment levels of depression and weight concern, and lower levels of general health and vitality. Reasons for discontinuing treatment were related to perceptions of the GSH programme; practicalities of the programme; and readiness to change. Whilst GSH can be effective for a sub-group of patients, factors such as pre-morbid level of depression, degree of weight concern, perceptions of the programme, and readiness to change may increase the likelihood of non-completion.

Is being underweight associated with impairments in quality of life in the absence of significant eating disorder pathology?

Few studies have compared low-weight individuals with eating disorder (ED) pathology with similar-weight individuals without significant pathology despite the fact that body weight is often used as a key outcome within ED research. This study compared quality of life (QoL) in one group with high levels of ED pathology to a group with low ED pathology, matched by body mass index (BMI). The high ED group reported significantly lower ED-specific quality of life (EDQoL) than the low ED group. These findings suggest that young women with high levels of ED pathology report significantly more impaired QoL than comparable young women with no ED pathology, and that being underweight alone is not a primary contributor to poorer EDQoL.

Stimulus discriminability in free-operant and discrete-trial detection procedures.

Six pigeons were trained to discriminate different light intensities in four experimental procedures. Experiment 1 compared stimulus discriminability in a yes-no signal-detection task with discriminability measures obtained from two free-operant procedures. Discriminability estimates were significantly lower in the detection procedure. Experiment 2 showed this lowered discriminability to be a function of the delay between stimulus presentation and the availability of the choice-response keys in the standard detection task. In addition, reinforcement sensitivity was lowest when correct choice responses were intermittently, rather than continuously, reinforced.