Can insulin prevent complications?

Someone posted the exact same long-winded rant about diabetes companies and stem cell research at several other blogs (not this one!). Although the author has some good points, others are purely misinformation. I just can't avoid commenting on one: he/she has the perverse notion that insulin "does not prevent the catastrophic side effects" of diabetes.

There is plenty of information that insulin can indeed prevent catastrophic side effects. The most obvious example is DKA: without insulin, diabetic ketoacidosis is the most catastrophic side effect of all, routinely resulting in death. Appropriate instructions to patients with T1DM to never withhold insulin therapy, even when sick and vomiting, has resulted in a dramatic decrease in this complication.

The DCCT, published way back in 1993, showed that tight control of blood sugar (with insulin, meal planning, exercise, and frequent BG testing) in people with T1DM resulted in an overwhelming difference in the chances of developing three major diabetic microvascular complications: there was a sixty-two percent reduction in relative risk of diabetic retinopathy, fifty-six percent less progression of kidney disease, and sixty percent less progression of neuropathy, in the intensively-treated group of patients, compared to those who were treated with "standard" care.

And for people with T2DM, the UKPDS showed the same: better blood glucose control reduces the risk of major diabetic eye disease by a quarter, and early kidney damage by a third.

The take-home message: Appropriate use of insulin will decrease the chances of complications.