Hemorheological effects of intensive diabetes management in the DCCT

Article type: Research Article

Authors: McMillan, Donald E. | Malone, John I.

Affiliations: University of South Florida College of Medicine and James A. Haley Veterans Hospital, Tampa, Florida, USA

Abstract: The Diabetes Control and Complications Trial (DCCT), an NIH-sponsored study at 29 institutions in the U.S. and Canada, began in 1983 to examine the effects of intensive blood glucose management on the complications of type I diabetes. About half of the 1441 patients studied were randomized into a conventional treatment group and half into an intensive management group. About half of each treatment group had diabetes of 1–5 years duration and no retinopathy at randomization (primary) and half had diabetes of 1–15 years duration and minimal retinopathy at randomization (secondary). Hemoglobin A1c levels were regularly measured. Information about complications collected systematically included retinal photographs, nerve conduction velocity assessment and evaluation of albuminuria and renal function. Differences in mean Hemoglobin A1c level between the intensively-treated group and the group continuing their usual treatment were sustained and substantial. Mean hemoglobin A1c levels were 1% compared to 3% above the normal range. We measured fibrinogen, haptoglobin, albumin and total protein levels of 1347 patients from April to August of 1991. Mean fibrinogen (measured both by coagulation quantification and clotting time after dilution) and haptoglobin were elevated and albumin level modestly depressed in the overall DCCT group and gender-based differences were also noted. Despite past reports linking diabetes control to plasma protein levels, no trend to normalization was found in the intensively treated group. In fact, mean haptoglobin level was modestly higher in the intensively treated compared to the conventional group. The primary and secondary prevention components had a well-defined difference in total plasma globulin, linked to marginal differences in albumin and total protein level. The globulin was higher in the secondary prevention group, who by study design manifested more microvascular changes. Intensive management of diabetes has no direct favorable effect on the levels of the major blood proteins that influence blood's flow properties.

Keywords: diabetes mellitus, type I diabetes, fibrinogen, haptoglobin, plasma albumin

DOI: 10.3233/CH-1994-14403

Journal: Clinical Hemorheology and Microcirculation, vol. 14, no. 4, pp. 481-488, 1994