<prompt> Which of the following is the most impoant factor in determining the development of diabetic nephropathy?Duration of the diseaseHypeensionPre-existing renal diseaseControl with treatment  <response>: Most impoant risk factor for development of diabetic nephropathy is the duration of diabetes. 30 of patients with type 1 diabetes develop microalbuminuria after 20 years of onset of diabetes. 5 -25 of patients develop clinically significant renal failure at the time of diagnosis and 30 develop ESRD at 20years duration. 