Public Health Service study on Reye's syndrome and medications. Report of the pilot phase

Between February and May 1984, we conducted a pilot study to examine the methods for a larger study of a previously reported relation between Reye's syndrome and medications. Thirty patients with Reye's syndrome, whose diagnosis was confirmed by an expert panel, and 145 controls were matched for age, race (black or not black), and antecedent illness (respiratory infection, chickenpox, or diarrhea) and selected from the same hospital, emergency room, or school, or identified by random digit dialing. Significantly more cases (93 per cent, 28 of 30) than members of each of the four control groups or all controls combined (46 per cent, 66 of 145) had received salicylates during matched antecedent illnesses (odds ratio of all 30 cases vs. all controls = 16.1; lower 95 per cent confidence limit = 4.6). The prevalence and mean severity score of signs, symptoms, and selected events during the antecedent illness tended to be lower among cases than controls. Thus, differences in the severity of this illness between cases and controls did not explain differences in medication exposures. This pilot study suggests an association between Reye's syndrome and the use of salicylates during an antecedent illness.