The momentary associations of negative affect, anxiety and stress with symptoms in individuals with anorexia nervosa: a scoping review

Negative affect, anxiety, and stress are common in individuals with anorexia nervosa (AN), but their momentary link to symptoms remains unclear. This review aims to (1) examine how negative affect, anxiety, and stress are associated with eating-disorder-related symptoms in the moment in individuals with AN and (2) explore how these concepts are conceptualised and measured across studies in this field. A systematic search following PRISMA-ScR guidelines was conducted across 11 databases. Eligible studies included individuals with a diagnosis of (atypical) AN, examined negative affect, anxiety, or stress, and reported outcomes related to AN symptoms. We identified 95 eligible studies, which we categorised into retrospective self-report, qualitative, experimental, and daily life studies. Across experimental paradigms, negative affect was primarily examined in relation to disorder-specific cognitions. In daily life studies, negative affect was associated with binge eating and purging, while associations with restriction and physical activity were mixed. Mealtime anxiety was related to caloric intake. Stress investigated using general stress paradigms yielded mixed findings for eating-disorder behaviours, with notable divergences between subjective and physiological stress responses. Few studies directly compared negative affect, anxiety, and stress within the same design, limiting conclusions regarding their relative importance. Negative affect, anxiety and stress are associated with disorder-specific cognitions and urges, though the translation into observable behaviour varies by context and subtype. Future research must address current gaps by adopting multi-modal assessments. Strengthening methodological consistency will be important for advancing the understanding of the interplay between affective states and symptoms in AN. People with anorexia nervosa often experience strong negative emotions, anxiety, and stress. This review brought together 95 studies to understand how these momentary feelings are linked to eating-disorder thoughts and behaviours in daily life and in research settings. The studies used many different approaches. Some relied on questionnaires or interviews, while others created emotional situations in a laboratory or tracked people’s feelings and behaviours in real time during everyday life. When emotions were deliberately triggered in laboratory studies, negative emotions were linked to stronger eating-disorder-related thoughts. In daily life studies, negative emotions were associated with binge eating and purging. However, findings were less consistent for eating less food or engaging in high levels of physical activity. Anxiety, especially around mealtimes or related to eating and body concerns, was often linked to how many calories a person consumed. Stress was usually studied using general stress tasks, such as social challenges. Its effects on eating behaviours were mixed, and people’s reported stress did not always match their body’s physical stress responses.