The Diabetes Control and Complications Trial (DCCT) was a
landmark study conducted from 1983 to 1993 designed to explore
whether intensive glucose control could delay or possibly even
prevent diabetes-related complications. In this study, intensive
control meant keeping hemoglobin A1C levels at 6% or less. Until
the DCCT, numerous studies pointed toward confirming the
hypothesis that lower glucose levels reduced the risk of
complications. But no long-term studies had conclusively proven
this. The study involved 1,141 volunteers, ages 13 to 39, with
type 1 diabetes and was conducted at 29 medical centers
throughout North America. The results of the 10-year study
showed that maintaining blood glucose levels in a more or less
normal range can slow the onset and progression of eye, kidney,
and nerve damage caused by diabetes. It further stated that any
lowering of blood sugar levels was beneficial even when the
person with diabetes had a history of poor glucose control. At
the close of the DCCT a follow-up study