How many diabetics need dialysis?

Big problem. Diabetes is the most common cause of new patients requiring dialysis, accounting for about 45 percent of cases in the United States. I am not sure what percentage of diabetics develop end-stage kidney disease, but it is declining due to a number of factors.
Depends. Diabetics can develop nephropathy where their kidney function deteriorates with time. The higher the blood sugars the faster the decline in kidney function which can lead to complete failure eventually needing dialysis. Certain medications such as ace inhibitors have been shown to delay the onset of kidney disease in diabetics.