Following informed written consent 96 diabetic patients will be randomly assigned to receive either an oral dose of daily B-group vitamins (5 mg folic acid, 5mg vitamin B-2, 50 mg vitamin B-6, 0.4 mg vitamin B-12) and antioxidant vitamins [800 IU (727mg) of a-tocopherol and 500mg of vitamin C] [n=48], or no supplements [n= 48] daily for 90 days. All subjects will have three assessments, at baseline, 3, and 12 months post-randomisation. The assessment will include markers of inflammation, endothelial dysfunction, oxidative stress, antioxidants, total plasma homocysteine and risk of infections. A fasting 15-ml of blood will be taken for measurements of total plasma homocysteine concentration, markers of inflammation, endothelial dysfunction, oxidative damage and vitamin concentrations. Further information on clinical variables which may influence endothelial dysfunction, antioxidant capacity, immunity and diabetes control status will be collected and adjusted for during analysis.
Potential Significance- the study will help to clarify the temporal relationships between , markers of inflammation, endothelial dysfunction and oxidative stress and risk of infections and form the basis of appropriate intervention strategies to minimise the long-term complications associated with type 2 diabetes mellitus.