Introduction: The increased platelet activity is recognized to play a role in the development of vascular complications of diabetes mellitus. Increased platelet activity is characterized by larger and young platelets. The mean platelet volume (MPV) is an indicator of the average size and activity of platelets. HbA1c indicates severity and propensity to develop complications. Diabetic retinopathy is one of the microvascular complications. Objectives

1. To estimate the mean platelet volume (MPV) in patients with diabetic retinopathy (DR).
2. To compare the MPV in patients with and without DR.
3. To assess the relationship between glycaemic control and MPV in diabetics.

Materials and methods: A cross sectional study conducted in 100 diabetic patients to assess the MPV, HbA1c levels and retinopathy due to diabetes. The patients were selected by systematic random sampling. They were examined in medicine ward and blood investigations were performed in KVGMCH laboratory. Observations: MPV in patients with and without diabetic retinopathy was estimated to be 9.15 ± 0.94 and 8.73 ± 0.85 respectively. The mean platelet volume in patients with diabetic retinopathy is more than those patients without retinopathy. This difference is statistically significant with p value < 0.05. As HbA1c value increase, MPV also increases significantly. This indicates that MPV is a reliable marker of vascular complications i.e. Diabetic retinopathy. Conclusion: Changes in MPV reflect the state of thrombogenesis. High MPV is emerging as a new risk factor for the vascular complications of DM of which atherothrombosis plays a major role. MPV can be used as a simple tool to monitor the progression and control of DM and its cardio-vascular complications.