Diabetic microangiopathy is in its developed form a serious complication for patients with diabetes, in particular diabetes type 1. An important aspect of prevention of organ damage is early assessment of factors which accelerate the development of microangiopathy. In the submitted paper the authors draw attention assessment of plasma fibrinogen, thrombocyte aggregation in relation to renal functions in type 1 diabetics as well as other indicators which promote the development and acceleration of diabetic nephropathy. In patients with diabetic nephropathy a correlation was found between fibrinogen and thrombocyte aggregation as well as between the rate of urinary albumin excretion, systolic and median blood pressure which are risk factors which increase the mortality of patients with type 1 diabetes.