Red blood cell distribution width predicts two-hours plasma glucose levels during OGTT

Red blood cell distribution width (RDW) is a numerical measure, reported as part of a standard complete blood count, usually employed for differential diagnosis of anemic state. Some lines of evidence demonstrate that RDW associates with type 2 diabetes incidence and its complications. To further explore the role of RDW as predictor of abnormal glucose metabolism, we have analyzed the relationship between RDW and 2-hours plasma glucose concentration during an oral glucose tolerance test (OGTT).

Forty-five outpatients were enrolled for the present study. Participants underwent 75 g OGTT and measurements of hematological parameters. Cardiovascular disease risk factors (blood pressure, blood lipids, cigarette smoking, obesity) were evaluated by routine methods.

In simple regression analysis 2-hours post-load glucose was directly associated with age (r = 0.36, p = 0.01), fasting glucose levels (r = 0.40, p = 0.002) and RDW (r = 0.31, p = 0.037). In multiple regression analysis fasting glucose, RDW, triglycerides and age significantly and independently predicted 2-hours plasma glucose (p <  0.01 for all coefficients).

The present findings demonstrate that RDW associates with plasma glucose concentration after a 75-g oral glucose tolerance test. Our results highlight the role of RDW as predictor of glucose metabolism disturbance.