 Complicated Grief and Autoimmune Diseases: The Other Epidemic? 
A little more than a century after the publication of “Mourning and Melancholia” by Freud, the impact of grief on the health of the deceased’s relatives, particularly in the case of complicated grief, has been widely established and extended to various psychological and/or somatic manifestations. The causality of autoimmune diseases in adults remains poorly understood and it is often stated that they have a multifactorial origin, with various environmental and genetic factors whose respective weights are unknown. In addition to infectious, toxic, medicinal and hormonal factors, psychological factors or “stress” are also regularly observed before the onset of an autoimmune disease. This article studies the hypothesis of a causal relationship between complicated grief and the occurrence of autoimmune diseases in adults. In the first part, data of interest from qualitative research carried out with patients suffering mainly from systemic lupus are analyzed, namely the data from the Brief Illness Perception Questionnaire from PSY-LUP multicenter study (Psychosocial Consequences of Systemic Lupus Erythematosus) patients; those from a specific survey on complicated grief (Lupus Mourning Survey), using the Inventory of Complicated Grief Revised and carried out among members of a lupus patients’ association; and, finally, the data of the INSIDE Study, a psychosomatic investigation of 50 patients suffering from various autoimmune diseases, carried out jointly by an internist and a psychologist/hypnotherapist. The second section includes an interdisciplinary scientific literature review involving the fields of medicine, neuro-immunology, ethology, anthropology, psychology and psychosomatics, organized according to Hill’s 9 criteria of causality. Finally, from the perspective of the biopsychosocial model, we discuss the possible implications and perspectives of our work in terms of avenues of research and management of patients suffering from autoimmune diseases, but also from other dysimmune pathologies such as cancer.