Multiple sclerosis and ionizing radiation.
The etiology of multiple sclerosis (MS) may involve exposure to infectious, chemical or physical agents damaging the blood-brain barrier and an autoimmune reaction against myelin breakdown products. Here we report a pooled analysis of 174 MS cases and 815 population controls from two case-control studies with regard to such a potentially damaging exposure, namely X-ray examinations, radiological work and treatment with ionizing radiation. Exposure was assessed by questionnaires to the subjects. We obtained odds ratios of 4.4 (95% confidence interval, CI, 1.6-11.6) and 1.8 (95% CI 1.2-2.6) for radiological work and X-ray examinations, respectively; 5 cases, but no controls, in one of the studies had been treated with ionizing radiation. Our data and some other observations reported in the literature suggest a contributory role for ionizing radiation to the development of MS in some cases.
Axelson
O
O
Division of Occupational and Environmental Medicine, Department of Health and Environment, Linköping University, Linköping, Sweden. olav.axelson@ymk.liu.se
Landtblom
A M
AM
Flodin
U
U
D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D004781:Environmental Exposure; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000453:epidemiology / Q000209:etiology*; D016273:Occupational Exposure; D016017:Odds Ratio; D011832:Radiation Injuries; D011859:Radiography / Q000009:adverse effects; D011878:Radiotherapy / Q000009:adverse effects