The effect of glucose variability on the risk of microvascular complications in type 1 diabetes.
OBJECTIVE
It is not known whether glycemic instability may confer a risk of microvascular complications that is in addition to that predicted by the mean blood glucose (MBG) value alone. This study has analyzed data from the Diabetes Control and Complications Trial (DCCT) to assess the effect of glucose variability on the risk of retinopathy and nephropathy in patients with type 1 diabetes.


METHODS
Pre- and postprandial seven-point glucose profiles were collected quarterly during the DCCT in 1,441 individuals. The mean area under the curve glucose and the SD of glucose variability within 24 h and between visits were compared with the risk of retinopathy and nephropathy, having adjusted for age, sex, disease duration, treatment group, prevention cohort, and phase of treatment.


RESULTS
Multivariate Cox regression showed that within-day and between-day variability in blood glucose around a patient's mean value has no influence on the development or progression of either retinopathy (P = 0.18 and P = 0.72, respectively) or nephropathy (P = 0.32 and P = 0.57). Neither preprandial (P = 0.18) nor postprandial (P = 0.31) glucose concentrations preferentially contribute to the probability of retinopathy.


CONCLUSIONS
This study has shown that blood glucose variability does not appear to be an additional factor in the development of microvascular complications. Also, pre- and postprandial glucose values are equally predictive of the small-vessel complications of type 1 diabetes.
Kilpatrick
Eric S
ES
Department of Clinical Biochemistry, Hull Royal Infirmary, Anlaby Road, Hull HU3 2JZ. eric.kilpatrick@hey.nhs.uk
Rigby
Alan S
AS
Atkin
Stephen L
SL
D000293:Adolescent; D000328:Adult; D001786:Blood Glucose / Q000378:metabolism*; D003922:Diabetes Mellitus, Type 1 / Q000150:complications*; D003930:Diabetic Retinopathy / Q000209:etiology*; D005260:Female; D006801:Humans; D008297:Male; D015999:Multivariate Analysis; D012044:Regression Analysis; D012306:Risk
D001786:Blood Glucose