Structural brain deviations in chemical intolerance: : A voxel-based morphometry study

Sammanfattning: Chemical intolerance (CI) is a term that refers to an affliction where a normally harmless smell couldgive reactions similar to those of allergy. There is no strong physiological evidence explaining thisphenomenon and therefore renders the affliction medically unexplained. Furthermore, there issymptomatic overlap between somatoform disorders, depression and medically unexplainedsymptoms such as chronic fatigue syndrome, fibromyalgia and various definitions of CI. Functionaland structural magnetic imaging has demonstrated metabolic, and gray matter density deviations inindividuals experiencing these symptoms. Such differences have been found in several similarlyunexplained medical conditions like, for example, fibromyalgia and chronic fatigue syndrome. This isan explorative study applying voxelbasedmorphometry on MR pictures from a CI (n=26) and ahealthy control (n=31) group in order to investigate possible regional brain structure deviations inthe CI group. The participants are all women aged 18 to 70 years. The results indicate significantgraymatterreduction in hippocampus, caudate and 13 other areas, which provides physiologicalevidence for long term stress as a contributor to the etiology of the affliction.