[Evaluation of risk factors of interferon-associated retinopathy in patients with type C chronic active hepatitis]

The risk factors of retinopathy associated with administration of interferon have not been fully clarified. We prospectively examined the retinal condition in 50 patients with type C chronic active hepatitis during alpha-interferon treatment. 43 patients (86%) were shown to have retinopathy during the course of interferon treatment, and were divided into three groups. Grades I, II and III were patients having a single episode of transient retinopathy with soft exudate or hemorrhage (34%), frequent episodes of retinopathy (42%), and exacerbating retinopathy requiring change or cessation of interferon treatment (10%), respectively. The patients with grade II and III were found to have the first retinal changes within 8 weeks after initiation of the interferon therapy. Early onset of retinopathy and presence of systemic disease such as diabetes mellitus or hypertension were risk factors for serious retinopathy with statistical significance. The grades of retinopathy were also well correlated with dosage and duration of interferon treatment. These results suggest that careful fundus examination is required up to 8 weeks after initiation of interferon treatment, especially for the patients with risk factors such as early onset of retinopathy, presence of systemic diseases, and large dosages and long duration of interferon therapy, in order to prevent serious ocular complications.