Mal de Debarquement Syndrome: a survey on subtypes, misdiagnoses, onset and associated psychological features

INTRODUCTION: Mal de Debarquement Syndrome (MdDS) is a neurological condition typically characterized by a sensation of motion, that persists longer than a month following exposure to passive motion (e.g., cruise, flight, etc.). The most common form of MdDS is motion triggered (MT). However, recently it has been acknowledged that some patients develop typical MdDS symptoms without an apparent motion trigger. These cases are identified here as spontaneous or other onset (SO) MdDS. This study aimed to address similarities and differences between the MdDS subtypes. Diagnostic procedures were compared and extensive diagnostic guidelines were proposed. Second, potential triggers and associated psychological components of MdDS were revealed. METHODS: This was a retrospective online survey study for MT and SO MdDS patients. Participants were required to respond to a set of comprehensive questions regarding epidemiological details, as well as the diagnostic procedures and onset triggers. RESULTS: There were 370 patients who participated in the surveys. It is indicated that MdDS is often misdiagnosed; more so for the SO group. In addition to the apparent self-motion, both groups reported associated levels of stress, anxiety and depression. DISCUSSION: It appears at present that both MdDS subtypes are still poorly recognised. This was the first attempt to evaluate the diagnostic differences between MdDS subtypes and to propose a set of comprehensive diagnostic guidelines for both MdDS subtypes. In addition, the current research addressed that associated symptoms such as stress, anxiety and depression should also be considered when treating patients. We hope this study will help the medical community to broaden their awareness and diagnostic knowledge of this condition. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s00415-017-8725-3) contains supplementary material, which is available to authorized users.