Ophthalmological Side Effects of Hepatitis C Treatment are Related to Vascular Endothelial Growth Factor Levels

Ophthalmological side effects, including vision problems, are sometimes reported by patients receiving interferon-based therapy for chronic hepatitis C.

To determine the incidence and cause of these adverse events, researchers prospectively screened interferon-treated patients for vascular ophthalmological side effects, and looked for evidence of activation of angiogenesis (proliferation of new blood vessels).

The study included 34 chronic hepatitis C patients; 18 were treated with 180 micrograms/week of pegylated interferon alfa-2a (Pegasys) plus 800 mg/day of ribavirin, while 16 received 1.5 micrograms/kg/week of pegylated interferon alfa-2b (Peg-Intron) plus 800-1200 mg/day of ribavirin.

Complete ophthalmological evaluation and serum levels of vascular endothelial growth factor (VEGF) -- a cytokine that promotes blood vessel proliferation -- were assessed before and at the end of therapy.

Results

13 patients (38.2%) developed vascular ophthalmological side effects during interferon therapy; 8 patients (23.5%) developed subconjunctival hemorrhage, and 5 (14.7%) had evidence of retinopathy.

In 3 of the 13 patients, visual acuity was affected, and 2 had residual lesions during post-treatment follow-up.

These side effects were not associated with age, sex, HCV genotype, antiviral schedule, type of interferon, or response to therapy.

At the end of treatment, the group with vascular ophthalmological side effects had significantly higher serum VEGF levels than the group without detectable ophthalmological side effects (281 vs 117 pg/mL; P = 0.05).

These differences increased when VEGF values were adjusted for platelet count.

In the ophthalmological side effects group, baseline VEGF (164 vs 64 pg/mL, P = 0.046) and VEGF/platelet values (0.920 vs 0.320 pg/106 platelets, P = 0.024) were also significantly higher.

In a multivariate model, VEGF/platelet values at the end of treatment and hepatic fibrosis stage were the only predictors of vascular ophthalmological side effects.

Conclusion

The authors concluded that in this exploratory study, antiviral therapy for chronic hepatitis C "frequently induces vascular ophthalmological side effects, apparently through an activation of angiogenesis."

7/21/06

Reference
R J Andrade, F J Gonzalez, L Vazquez, and others. Vascular ophthalmological side effects associated with antiviral therapy for chronic hepatitis C are related to vascular endothelial growth factor levels. Antiviral Therapy 11(4): 491-498. 2006.