A nine-year follow-up of people diagnosed with multiple chemical sensitivities.

The authors assessed self-reported health status and clinical symptoms in people reporting multiple chemical sensitivities (MCS) at a 9-year follow-up interview using structured and semistructured instruments and self-report questionnaires. Of the original sample, 18 people (69%) consented to an interview. By use of the best estimate diagnostic method, 15 subjects (83%) met DSM-IV criteria for a lifetime mood disorder, 10 (56%) for a lifetime anxiety disorder, and 10 (56%) for a lifetime somatoform disorder. None of the subjects met the criteria for a substance use disorder (current or lifetime). The Illness Behavior Questionnaire and the Symptom Check-list-90-Revised results showed little change from 1988 and remained significantly different from the control group on many subscales. The authors conclude that the subjects remain strongly committed to the diagnosis of MCS, and although improved since their original interview, many remain symptomatic and continue to report ongoing lifestyle changes.