Objectives To assess the level of deterioration in functioning of ED patients during confinement, due to COVID-19, and examine potential contributing factors (coping strategies, anxiety-depressive symptomatology and personality traits). Methods A total of 74 ED patients in treatment before the COVID-19 outbreak, contributed to this study. Baseline pre-treatment evaluation included the SCL-90R, TCI-R, EDI-2 and Y-FAS 2.0 questionnaires for general psychopathology, personality and ED severity indexes. ED symptoms, coping strategies, socio-demographic data and COVID-19 concerns were collected by clinicians through a semi-structured telephone survey during lockdown. Results A deterioration in ED symptoms and general psychopathology (anxiety and depression), during lockdown, was associated with low self-directedness. Higher ED symptomatology during confinement was associated with less-adaptive coping strategies to deal with lockdown situation leading to an increase in weight. Conclusions These specific vulnerability factors to further confinement or stressful situations may help design personalized preventive and therapeutic approaches.