Psychological features of subjects with idiopathic environmental intolerance

Objectives: Idiopathic environmental intolerance (IEI) is associated with u nexplained symptoms attributed to nonnoxious levels of environmental substa nces. Clinically, some of the symptoms of IEI overlap with those of panic d isorder (PD). We have recently reported a link between IEI and panic respon ses to a single inhalation of 35% carbon dioxide (CO2), a reliable panic in duction challenge. This study assessed depression, stress, anxiety, and ago raphobic symptoms among IEI subjects from our previous study versus healthy controls. Methods: Thirty-six IEI and 37 control subjects with no preexist ing psychiatric history were compared on self-report psychological question naires. Results: IEI subjects scored significantly higher than controls on the Agoraphobic Cognitions Questionnaire (ACQ), Depression Anxiety Stress S cales (DASS), and Mobility Inventory for Agoraphobia (MI) (Student's t, P < .05). Conclusions: IEI subjects represent a group with morbidity significa ntly higher than a control population but less than what would be expected for a clinical psychiatric population. (C) 2001 Elsevier Science Inc. All r ights reserved.