Interaction between HLA-DR2 and abnormal brain MRI in optic neuritis and early MS

The association of the human leukocyte antigen (HLA)-DR2 allele with brain MRI signal. abnormalities and with the development of MS was assessed in 17 8 patients enrolled in the Optic Neuritis Treatment Trial. HLA haplotype DR 2 was present in 85 (48%) of the 178 patients. Its presence was associated with increased odds of probable or definite MS at 5 years (odds ratio, 1.92 ; 95% confidence interval, 1.01 to 3.67; p = 0.04). The association was mos t apparent among patients with signal abnormalities on baseline brain MRI.