Psychological Predictors of Short- and Medium Term Outcome in Individuals with Idiopathic Environmental Intolerance (IEI) and Individuals with Somatoform Disorders

Abstract

Idiopathic environmental intolerance (IEI), also known as multiple chemical sensitivity (MCS), is defined as a chronic polysymptomatic condition that cannot be explained by an organic disease. Previous studies suggest that IEI may be a variant of somatoform disorders (SFD), because both disorders overlap with respect to symptoms and psychological features of somatization. However, little is known about the short- and medium-term outcome of IEI and psychological outcome predictors. Two clinical groups (IEI and SFD) and a comparison group (CG) were followed through 32 mo to assess both the outcome, and the extent to which trait anxiety and somatic symptom attribution (assessed at first examination) predict outcome presented 12 and 32 mo later. Outcome measures were the number of self-reported IEI symptoms, IEI triggers, IEI-associated functional impairments, and the number of somatoform symptoms. In addition, the course of the 2 syndromes over the 32-mo follow-up period was investigated with standardized screening scales. The 3 diagnostic groups consisted of 46 subjects with IEI, 38 subjects with SFD but without IEI, and 46 subjects (CG) with neither IEI nor SFD. Syndrome stability was high over the 32-mo follow-up period, and at both follow-ups IEI and non-IEI subjects differed on all IEI outcome measures (symptoms, triggers, functional impairments). Both trait anxiety and somatic attribution (the tendency to attribute common somatic complaints to an illness) predicted outcome. In addition, somatic attribution was found to partially mediate the effect of trait anxiety on outcome in the IEI group. In conclusion, these results suggest that IEI is a chronic and disabling condition and that trait anxiety contributes to the maintenance of the disorder via somatic attributions.

Evaluation of subjective symptoms of Japanese patients with multiple chemical sensitivity using QEESI©

“…MCS, also known as idiopathic environmental intolerance (IEI), is a syndrome which progresses to multiple organ dysfunction, mainly involving the autonomic nervous system, with extremely low-level chemical exposure [2][3][4][5][6][7][8][9][10]. However, the pathogenesis and underlying mechanisms have not been fully clarified anywhere in the world, and internationally unified diagnostic criteria for MCS have not been established [1].…”

Chemical Intolerance in Primary Care Settings: Prevalence, Comorbidity, and Outcomes

“…26,27 A substantial subset of affected individuals also report multiple food intolerances, [28][29][30] and several studies have demonstrated food triggers in a subset of children with attention-defi cit/hyperactivity disorder (ADHD), migraine, and epilepsy, [31][32][33][34][35][36] as well as adults with schizophrenia. 37,38 Although some investigators label these patients as having somatoform spectrum disorder, 11,39,40 the mean age of onset is typically older than 30 years, 12 a fi nding that is inconsistent with the diagnostic criterion requirement for the earlier age of onset in the Diagnostic and Statistical Manual of Mental Disorders (4th Edition) (DSM-IV) for classic somatization disorder. 41 Apart from etiology, elevated levels of subjective mental distress (eg, somatization, anxiety, depression) are a major factor in increasing health care use across diagnoses in the general population.…”

Electromagnetic hypersensitivity in the light of empirical results

“…Ezúton végeredményben a prediszpozíciók (a szorongásra, a szomatizációra és a szomatoszenzoros amplifikációra való fokozott hajlam) megerôsítik a tünetek és a környezeti hatások vélt oksági kapcsolatát (Bailer, Witthöft, & Rist, 2008). Utolsó lépésként ezek az emberek elektromágne-sesen túlérzékenynek címkézik magukat, ami visszahatva, a médiát és a hatóságokat figyelmeztetésekre és óvintézkedésekre sarkallja.…”