Type 1 Diabetes Complications Halved by Intensive Glycemic Control

New research shows that the rates of serious complications among individuals with type 1 diabetes appear lower than reported historically, especially when patients are treated intensively.

Recognizing that few longitudinal studies “describe the clinical course of type 1 diabetes mellitus (T1DM) in the age of intensive therapy” an international team of researchers analyzed results of the Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions and Complications (DCCT/EDIC), and Pittsburgh Epidemiology of Diabetes Complications Experience (EDC), in order to “to describe the current-day clinical course of T1DM.”

Reported in the Annals of Internal Medicine the study found that in a DCCT cohort of 1441 subjects “and a subset of the EDC cohort (n = 161) selected to match DCCT entry criteria,” intensive therapy—3 or more daily insulin injections or an insulin pump—resulted in “substantially lower cumulative incidences” of proliferative retinopathy, nephropathy, and cardiovascular disease.

Cumulative incidences for conventional therapy—1 to 2 daily insulin injections with no specific glycemic targets—were 50% (retinopathy), 25% (nephropathy), and 14% (cardiovascular disease) in the DCCT group and 47%, 17%, and 14% in the EDC group. The intensive therapy group had incidences of 21%, 9%, and 9% “and fewer than 1% became blind, required kidney replacement, or had an amputation because of diabetes during that time.”

The authors note that there is difficulty in making exact historical comparisons due to various methods of establishing complications, but believe that results of the study can “supply clinicians with a realistic description of clinical outcomes that they can discuss with their patients who have had their type 1 diabetes mellitus in the past 25 years.”

Additionally, as intensive diabetes therapy is now the standard of care, the authors expect a “more than 50 percent reduction in the rates of complication over time,” recommending implementation “early in the course of diabetes” for the most “powerful salutary effect.”