Activated protein C resistance in young adults with central retinal vein occlusion

Background-Central retinal vein occlusion is a disease that is most common in old people. While the disease in old people often is associated with atherosclerosis, hypertension, diabetes, or glaucoma, this is much less evident in young people. However, a new defect in the anticoagulant system has recently been discovered, activated protein C resistance. This hereditary defect may well be associated with central retinal vein occlusion, and so this factor was analysed in patients younger than 50 years with a history of central retinal vein occlusion. Methods-Blood samples were obtained from 31 patients younger than 50 years with a history of central retinal vein occlusion, and analysed for activated protein C resistance with standard clinical laboratory methods. Results-In this material 26% of all the patients and 36% of the patients younger than 45 years were resistant to activated protein C. The normal incidence of activated protein C resistance is 2-7%. Conclusion-Activated protein C resistance seems to be the most common known cause of central retinal vein occlusion in young people.