Vitamin D Levels in Patients With Central Retinal Vein Occlusion- a Prospective Controlled Study

The study will last one year and is expected to include 120 patients with RVO and 120 control patients. The first 10 RVO patients visiting St. Erik's Eye Hospital with disease duration of maximum 3 months will be included in the study each month. The control patients will be chosen randomly by the Central Bureau of Statistics and matched for age and gender according to disease distribution known from previous studies. The control group will receive a letter with information of the study, informed consent form and details about the blood sampling procedure. Every month 50 patients in the control group will be invited to participate in the study. Only the first 10 control subjects will be included in the study. Each month a blood sample will be taken from 10 patients with RVO and 10 subjects in the control group. All the subjects will only have one blood sample taken during the study. Blood will be analyzed to measure the vitamin D level. Vitamin D levels will be compared at the end of the study between groups and evaluated according to the time of year for sampling. All the blood sampling will be done by the laboratory at Karolinska University Hospital. Participation in the study is completely voluntary. The details of the study has been reviewed and approved by the Ethics Committee.