Taking a Deeper Dive Into OSFED Subtypes: A Meta-Analysis and Systematic Review

A meta-analysis of mortality rates in eating disorders: An update of the literature from 2010 to 2024

Elevated mortality rates have been reported in individuals with eating disorders (EDs). However, no meta-analysis in the past decade has provided an updated, comprehensive synthesis of mortality across all ED diagnoses while exploring potential moderating factors. We conducted a systematic search in four databases (PsycINFO, MEDLINE, Embase and Web of Science) from 2010 to 29 Oct 2024. Studies that reported standardized mortality ratios (SMRs) in individuals with a diagnosed ED (including formal diagnoses and self-reports) were included. Random-effects meta-analyses were conducted to pool estimates across studies. Meta-regression was conducted to examine predictors of heterogeneity. Meta-analysis of SMRs of effect sizes revealed elevated mortality risk for individuals with an ED (regardless of ED subtype); weighted SMR = 3.39 (95 % CIs: 2.90, 3.95), p < .001, I2 = 95.1 %, Q(df=73) = 1492.39, p < .001. SMRs were highest for individuals with anorexia nervosa (5.21; k = 30), followed by eating disorder not otherwise specified (2.51; k = 8); bulimia nervisa (2.20; k = 18) and binge eating disorder (1.46; k = 3). Individuals with EDs demonstrate markedly heightened mortality rates, especially among those with anorexia nervosa. Our findings are crucial for identifying key factors influencing mortality in EDs, guiding targeted interventions to reduce preventable deaths.

A Narrative Review on the Neurocognitive Profiles in Eating Disorders and Higher Weight Individuals: Insights for Targeted Interventions

Background/Objectives: Recent research has increasingly explored the cognitive processes underlying eating disorders (EDs), including anorexia nervosa (AN), bulimia nervosa (BN), binge eating disorder (BED), other specified feeding or eating disorders (OSFEDs), and individuals with higher weight (HW). This critical narrative review focuses on neurocognitive findings derived from mainly experimental tasks to provide a detailed understanding of cognitive functioning across these groups. Where experimental data are lacking, we draw on self-report measures and neuroimaging findings to offer supplementary insights. Method: A search of major databases that prioritized meta-analyses and recent publications (last 10 years) was conducted. Using comprehensive search terms related to EDs, HW, and neurocognition, eligible studies focused on human neurocognitive outcomes (e.g., cognitive flexibility, attentional bias, etc.) published in English were selected. Results: We found that some neurocognitive characteristics, such as cognitive rigidity, impulsivity, emotion processing difficulties, and dysregulated reward processing, appear transdiagnostic, spanning multiple ED subtypes and HW populations. We also revealed neurocognitive features specific to ED subtypes and HW. For instance, individuals with AN demonstrate an enhanced focus on detail, and BN and BED are characterized by a pronounced attentional bias toward food-related stimuli. In individuals with HW, cognitive processes underpin behaviours associated with overeating and weight gain. Conclusions: These findings highlight the critical importance of understanding both the unique and shared neurocognitive patterns across ED subtypes and HW populations. By identifying transdiagnostic factors, such as cognitive rigidity and reward processing, alongside ED subtype/HW-specific vulnerabilities, researchers and clinicians can develop more nuanced, evidence-based interventions that address the core mechanisms driving disordered eating behaviours.

Guidelines for Rigorous and Reproducible Research on Other Specified Feeding or Eating Disorder: Commentary on Dang et al. (2024)

Dang et al.'s review concludes that atypical anorexia nervosa (atypical AN), purging disorder (PD), and night eating syndrome (NES) are clinically significant and severe eating disorders (EDs). However, findings are unlikely to alter their status in future editions of the DSM due to limitations in the literature to date. Guidelines are offered to promote rigorous and reproducible research on other specified feeding or eating disorder OSFED. First, published research diagnostic criteria for atypical AN, PD, and NES should be consistently used to ensure findings across studies reflect the same conditions. Second, operational definitions are recommended for "recurrent" as at least twice within a 3-month period, minimum duration as at least 1 month, and "significant weight loss" as >5% BMI reduction within 1 month. Third, Thomas's and Gydus's trumping scheme for differential diagnosis of OSFED subcategories is endorsed but should prioritize identifying treatment targets based on medical morbidity over mirroring existing diagnostic algorithms. Fourth, a systematic approach for establishing clinical significance is recommended that explicitly notes medical risk associated with malnutrition, purging and nonpurging behaviors, and relevance of marked distress related to binge eating and body image disturbance. Adoption of these guidelines will facilitate necessary research on clinical utility.

Balancing Objective Markers and Subjective Experience in Eating Disorder Diagnoses: Commentary on Dang et al. (2024)

The results of Dang et al.'s recent systematic review and meta-analysis suggested that individuals diagnosed with other specified feeding or eating disorder (OSFED) and those diagnosed with specified eating disorders (EDs, such as bulimia nervosa) endorse similar, elevated levels of ED-related cognitions (but not behaviors). The DSM has traditionally conceptualized EDs primarily as disturbances in eating behavior, and the diagnostic boundaries for EDs are based on objective markers, such as behavioral frequencies and weight. Although focusing on objective markers for ED diagnoses and severity indices has advantages (e.g., clinical communication, measurement), pitfalls include diagnostic migration and low emphasis on ED cognitions. Dang et al.'s findings provide a basis for rethinking DSM's conceptualization of EDs as primarily behavioral. This commentary discusses the potential merits and challenges of emphasizing subjective cognitions when assigning ED diagnoses. We explore how objective markers (e.g., behavioral frequency, weight) and subjective experience (e.g., fear of weight gain) may be balanced to improve the clinical utility of ED diagnoses. In all, research that more deeply phenotypes the subjective experiences of people with EDs across contexts, identities, and cultures will enrich our understanding of eating pathology and may inform diagnostic revisions.

Drowning in Medicalization? Commentary on: Dang et al. "Taking a Deeper Dive Into OSFED Subtypes: A Systematic Review and Meta-Analysis"

The study by Dang and colleagues in this issue is a timely reminder of the need for careful consideration when it comes to the inclusion of putative new diagnoses in the diagnostic and statistical manual of mental disorders (DSM). The authors conclude that findings from their systematic review and meta-analysis of recent literature bearing on the DSM-5 other specified feeding and eating disorders (OSFED) category "support the conceptualization of atypical AN, PD and NES as clinically significant EDs with similar severity to full-threshold EDs." This commentary attempts to provide some additional context, historical context in particular, that the author believes may be helpful when considering the potential implications of Dang and colleagues' findings. This is achieved through reference to the construct, well-known in the sociology and feminist literature, of medicalization and by highlighting certain issues relevant to the determination of "clinical significance." I hope that readers approaching Dang and colleagues' research from the currently dominant, medical-model perspective might be persuaded of the importance of considering alternative perspectives when interpreting findings from research of this kind.