12-year followup study of epidemic Spanish toxic oil syndrome.

OBJECTIVE: To determine the longterm clinical and functional outcome among a large group of patients with toxic oil syndrome (TOS). METHODS: One hundred individuals with onset in 1981 were randomly selected for followup in 1993 from a national TOS database. Clinical and laboratory data for 1981 were collected by retrospective chart review. Ninety-one survivors were reevaluated in 1993 by direct interview, examination, the Health Assessment Questionnaire (HAQ), and the visual analog scale (VAS) for pain. A semiquantitative Total Clinical Score (TCS) was created to assess relative global outcome in 1993, for comparison with the HAQ, and for developing a predictive model based on disease manifestations at onset. RESULTS: Fifty-eight percent continue to have symptoms consisting predominantly of muscle cramping (60%), fatigue (55%), arthralgias (43%), subjective cognitive impairment (44%), psychiatric disease (27%), and soft tissue tenderness (22.5%). Severe neuromuscular sequelae, sclerodermatous skin disease, or pulmonary hypertension were not detected. The most notable laboratory findings at followup were hypercholesterolemia (55%) and hyperglycemia (14.5%). A good correlation was demonstrated between both the HAQ and the VAS for pain with the TCS. A statistical model indicated that alopecia, Raynaud's phenomenon, and sensory neuropathy were predictive of outcome. CONCLUSION: TOS is commonly associated with longterm neuromuscular and articular disease. Multiple factors implicated in the adaptation to chronic disease may contribute to this morbidity.