Abstract: Eighty two patients with isolated optic neuritis were studied prospectively to determine the frequency with which multiple sclerosis developed and the factors which increased its risk. Patients were followed for 6 to 264 months (mean, 57 months). Twenty six patients (32%) developed clinically definite or probable multiple sclerosis during the period of follow-up. Actuarial analysis predicted that 42% would develop multiple sclerosis by 7 years. Of those patients who developed multiple sclerosis, 92% had symptoms within 4 years of the first attack of optic neuritis. The highest incidence of multiple sclerosis occurred in the 21-40 year age group. There was an increased risk of MS in patients with HLA-DR2 and HLA-B7 tissue types. The frequency of HLA-DR4 was increased in patients with optic neuritis alone compared to controls and to patients with multiple sclerosis, but further studies are required to confirm this finding. 
Question: Does the abstract contain any numerical data?
Yes