Does glucose variability influence the relationship between mean plasma glucose and HbA1c levels in type 1 and type 2 diabetic patients?

TY - JOUR

T1 - Does glucose variability influence the relationship between mean plasma glucose and HbA1c levels in type 1 and type 2 diabetic patients?

AU - Kuenen, Judith C

AU - Borg, Rikke

AU - Kuik, Dirk J

AU - Zheng, Hui

AU - Schoenfeld, David

AU - Diamant, Michaela

AU - Nathan, David M

AU - Heine, Robert J

AU - ADAG Study Group

PY - 2011/8

Y1 - 2011/8

N2 - OBJECTIVE: The A1C-Derived Average Glucose (ADAG) study demonstrated a linear relationship between HbA(1c) and mean plasma glucose (MPG). As glucose variability (GV) may contribute to glycation, we examined the association of several glucose variability indices and the MPG-HbA(1c) relationship.RESEARCH DESIGN AND METHODS: Analyses included 268 patients with type 1 diabetes and 159 with type 2 diabetes. MPG during 3 months was calculated from 7-point self-monitored plasma glucose and continuous glucose monitoring. We calculated three different measures of GV and used a multiple-step regression model to determine the contribution of the respective GV measures to the MPG-HbA(1c) relationship.RESULTS: GV, as reflected by SD and continuous overlapping net glycemic action, had a significant effect on the MPG-HbA(1c) relationship in type 1 diabetic patients so that high GV led to a higher HbA(1c) level for the same MPG. In type 1 diabetes, the impact of confounding and effect modification of a low versus high SD at an MPG level of 160 mg/dL on the HbA(1c) level is 7.02 vs. 7.43 and 6.96 vs. 7.41. All GV measures showed the same tendency.CONCLUSIONS: In only type 1 diabetic patients, GV shows a significant interaction with MPG in the association with HbA(1c). This effect is more pronounced at higher HbA(1c) levels. However, the impact of GV on the HbA(1c) level in type 1 diabetes is modest, particularly when HbA(1c) is close to the treatment target of 7%.

AB - OBJECTIVE: The A1C-Derived Average Glucose (ADAG) study demonstrated a linear relationship between HbA(1c) and mean plasma glucose (MPG). As glucose variability (GV) may contribute to glycation, we examined the association of several glucose variability indices and the MPG-HbA(1c) relationship.RESEARCH DESIGN AND METHODS: Analyses included 268 patients with type 1 diabetes and 159 with type 2 diabetes. MPG during 3 months was calculated from 7-point self-monitored plasma glucose and continuous glucose monitoring. We calculated three different measures of GV and used a multiple-step regression model to determine the contribution of the respective GV measures to the MPG-HbA(1c) relationship.RESULTS: GV, as reflected by SD and continuous overlapping net glycemic action, had a significant effect on the MPG-HbA(1c) relationship in type 1 diabetic patients so that high GV led to a higher HbA(1c) level for the same MPG. In type 1 diabetes, the impact of confounding and effect modification of a low versus high SD at an MPG level of 160 mg/dL on the HbA(1c) level is 7.02 vs. 7.43 and 6.96 vs. 7.41. All GV measures showed the same tendency.CONCLUSIONS: In only type 1 diabetic patients, GV shows a significant interaction with MPG in the association with HbA(1c). This effect is more pronounced at higher HbA(1c) levels. However, the impact of GV on the HbA(1c) level in type 1 diabetes is modest, particularly when HbA(1c) is close to the treatment target of 7%.

KW - Adolescent

KW - Adult

KW - Aged

KW - Blood Glucose/metabolism

KW - Diabetes Mellitus, Type 1/blood

KW - Diabetes Mellitus, Type 2/blood

KW - Female

KW - Glycated Hemoglobin A/metabolism

KW - Humans

KW - Male

KW - Middle Aged

KW - Young Adult

U2 - 10.2337/dc10-2217

DO - 10.2337/dc10-2217

M3 - Journal article

C2 - 21700921

SN - 1064-9131

VL - 34

SP - 1843

EP - 1847

JO - Diabetes Care. Supplement

JF - Diabetes Care. Supplement

IS - 8

ER -