NEW YORK (Reuters Health) – The results of a 30-year study indicate that intensive glucose control can substantially reduce the rates of retinopathy, nephropathy, and cardiovascular disease in patients with type 1 diabetes.

“The demonstration that near-normal glucose control substantially lowers microvascular and cardiovascular complications has heralded a new era of type 1 diabetes care,” lead author Dr. David M. Nathan, from Massachusetts General Hospital, Boston, said in a statement.

“The remarkable improvement in long-term outcomes achieved with glucose control,” he added, “should encourage clinicians and patients alike to implement intensive therapy as early in the course of type 1 diabetes as possible,” he added.

The new findings, reported in the Archives of Internal Medicine for July 27, stem from a follow-up study of 1441 patients who were enrolled in the Diabetes Control and Complications Trial (DCCT) from 1983 to 1993.

As part of DCCT, subjects were randomized to intensive or conventional therapy. The goal with the former was to achieve near-normal glucose levels by using three or more insulin injections per day or with an insulin pump. With the latter therapy, by contrast, just 1 or 2 daily insulin injections were given with no attempt to achieve specific glucose levels. In 1993, DCCT became an observational study and, in light of the encouraging results with intensive therapy, this treatment was recommended for all patients.

Also included in the current analysis were 161 patients from the Pittsburgh Epidemiology of Diabetes Complications (EDC) study who had received conventional therapy. Subjects from this cohort and from the DCCT study were followed through 2005.

In the DCCT conventional therapy group, the rates of proliferative retinopathy, nephropathy, and cardiovascular disease were 50%, 25%, and 14%, respectively. The corresponding rates in the EDC conventional therapy group were similar: 47%, 17%, and 14%. The DCCT intensive therapy group, by contrast, had much lower rates: 21%, 9%, and 9%.

The results also show that less than 1% of patients treated with intensive therapy became blind, required kidney transplantation, or had a diabetes-related amputation.

“These data give clinicians a realistic description of the clinical outcomes they can discuss with their patients,” Dr. Nathan said. “When intensive therapy, now the standard of care, is implemented early in the course of diabetes, most patients with type 1 diabetes should be able to avoid the disastrous long-term complications that were so common in the past.”

Reference:
Arch Intern Med 2009;169:1307-1316.