Fasting and post-prandial glycemia and their correlation with glycated hemoglobin in Type 2 diabetes.
OBJECTIVE
The relative contribution of fasting and post-prandial glucose to glycated hemoglobin (HbA1c) is controversial. In the present study, we assessed the relationship with HbA1c of fasting and post-prandial glucose measured in a more naturalistic setting, through home glucose self-monitoring or with a continuous glucose monitoring system (CGM).


METHODS
A consecutive series of 300 patients with Type 2 diabetes were enrolled in the study, provided that they performed blood glucose self-monitoring. HbA1c and fasting plasma glucose (FPG) were measured at enrolment.


RESULTS
Both fasting plasma and capillary glucose showed a significant correlation with HbA1c (r=0.66 and 0.61, respectively; p<0.001). When home glucose monitoring was considered, both mean fasting and post-prandial glucose showed a significant correlation with HbA1c (r=0.71 and 0.73, respectively). In patients in the lower tertile of body mass index (BMI), HbA1c showed a significant correlation at multivariate analysis with post-prandial glucose, but not with fasting glucose. In patients with HbA1c >7%, both fasting and post-prandial glucose showed a significant correlation, after adjustment for age and BMI, with HbA1c (both p<0.01); conversely, in those with HbA1c < or =7%, such a correlation could be observed for fasting (p<0.01), but not for post-prandial glucose.


CONCLUSIONS
In conclusion, both fasting and post-prandial glucose contribute to the determination of HbA1c . Home glucose self-monitoring appears to provide a more accurate assessment of metabolic control than a single plasma glucose measurement in experimental conditions. Fasting glucose could provide a greater contribution to HbA1c in patients with lower HbA1c, while post-prandial glucose seems to play a major role in leaner Type 2 diabetic subjects.
Monami
M
M
Geriatric Unit, Department of Critical Care, University of Florence Medical School, 50141 Florence, Italy. mmonami@libero.it
Lamanna
C
C
Lambertucci
L
L
Longo
R
R
Cocca
C
C
Addante
F
F
Lotti
E
E
Masotti
G
G
Marchionni
N
N
Mannucci
E
E
D000368:Aged; D001786:Blood Glucose / Q000032:analysis*; D015190:Blood Glucose Self-Monitoring / Q000706:statistics & numerical data; D001794:Blood Pressure; D015992:Body Mass Index; D002784:Cholesterol / Q000097:blood; D003924:Diabetes Mellitus, Type 2 / Q000097:blood*; D005215:Fasting / Q000097:blood*; D005260:Female; D006442:Glycated Hemoglobin / Q000032:analysis*; D006801:Humans; D008297:Male; D008875:Middle Aged; D019518:Postprandial Period; D013223:Statistics as Topic
D001786:Blood Glucose; D002784:Cholesterol; D006442:Glycated Hemoglobin