Developing Case Definitions for Symptom-based Conditions: the Problem of Specificity

Hypersensitivity to exposure to electric and magnetic fields (EMFs) has been reported for nearly 20 years; however, the literature on the subject is still very limited. Nearly all the literature published concerns a dermatological syndrome that consists of mainly subjective symptoms (itching, burning, dryness) and a few objective symptoms (redness, dryness) appearing after individuals begin working with video display units and decreasing during absence from work. Case-control studies as well as some good but limited double-blind trials have not found any clear relationship between this syndrome and exposure to EMFs. A "general syndrome" with more general symptoms has been rarely described but seems to have a worse prognosis. The symptoms often associated with skin disorders are mainly of neurasthenic type and can cover a lot of nonspecific symptoms present in other atypical syndromes such as multiple chemical sensitivity or chronic fatigue. Most of these symptoms are allegedly triggered by exposure to different sources of EMFs, but there have been no valid etiological studies published on this more general syndrome. It appears that the so-called hypersensitivity to environmental electric and magnetic fields is an unclear health problem whose nature has yet to be determined.

Section: Discussionmentioning

confidence: 99%

Section: Experimental Studiesmentioning

confidence: 99%

Hypersensitivity of human subjects to environmental electric and magnetic field exposure: a review of the literature.

Levallois

2002

“…For example, multiple chemical sensitivity reflects, in the minds of some investigators, respectively, irritation in underlying chronic sinusitis, conditioned psychological responses to external stimuli, misinterpretation of a normal sensation, and an obsessive-compulsive personality disorder. Case definitions do not imply cause (54,55). No case definitions even exist for sick building syndrome.…”

Section: Symptoms Exposures and Disabilitymentioning

confidence: 99%

Indoor environmental exposures and symptoms.

Hodgson

2002

The label "sick building syndrome" is often used to imply the absence of a physiologic basis for symptoms in the built environment. Although building-related illness is widely recognized but considered rare, several well-studied mechanisms may be responsible for many symptoms in buildings. These mechanisms do not explain why some individuals perceive disability. Until researchers distinguish physiologic mechanisms from other aspects of disease and study them systematically, poorly defined symptoms will remain poorly understood. The disability associated with such symptoms and syndromes, not the physiology, is the primary interest and generates controversy.

“…A number of terms that describe a majority of these clusters of medically unexplained symptoms have been accumulating in the literature for several decades. These terms include somatization, somatization symptoms, medically unexplained physical symptoms, multiple medically unexplained symptoms, persistent symptom syndromes, symptombased conditions (Hyams 1998), functional somatic symptoms, and functional somatic syndromes, among others.…”

Section: Nosological Issuesmentioning

confidence: 99%

Medically unexplained physical symptoms in medical practice: a psychiatric perspective.

Escobar

Hoyos-Nervi

Gara

2002