Is fasting glucose variability a risk factor for retinopathy in people with type 2 diabetes?
OBJECTIVE
Fasting plasma glucose variability strongly predicts the incidence of cardiovascular events in type 2 diabetic patients. We prospectively assessed whether fasting plasma glucose variability predicts the development/progression of retinopathy in a large cohort of type 2 diabetic outpatients.


METHODS
In the period 1996-1999, 1019 type 2 diabetic participants (aged 69+/-11 years) in the Verona Diabetes Study underwent at least 3 fasting plasma glucose (FPG) determinations and an eye examination by retinography. Of these, 746 underwent a 2nd eye examination in the period 2000-2004, while 273 did not (102 patients had died before undergoing the 2nd eye examination). For each patient, the mean (M-FPG) and the coefficient of variation of FPG (CV-FPG) were computed.


RESULTS
By the 2nd eye examination, 124 patients had either developed new retinopathy (79 patients) or progressed to a more severe degree of retinopathy (45 patients). In a multivariable logistic regression analysis, the development/progression of retinopathy was independently predicted by average glycaemia over time, expressed as glycated haemoglobin (odds ratio [OR] 1.82, 95%CI 1.40-2.38 for 1 SD increase) or M-FPG (OR 1.88, 1.47-2.41), but not by CV-FPG. Among other independent variables, HDL-cholesterol was inversely associated with the development/progression of retinopathy.


CONCLUSIONS
These results suggest that in elderly type 2 diabetic patients the magnitude of hyperglycaemia, but not fasting plasma glucose variability, strongly predicts the development/progression of diabetic retinopathy independently of other known risk factors.
Unit of Endocrinology and Metabolic Diseases, University of Verona, Verona Italy.
G
G
Zoppini
G
G
Verlato
G
G
Targher
S
S
Casati
E
E
Gusson
V
V
Biasi
F
F
Perrone
E
E
Bonora
M
M
Muggeo
D000368:Aged; D001786:Blood Glucose / Q000032:analysis*; D015331:Cohort Studies; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000150:complications*; D003930:Diabetic Retinopathy / Q000097:blood / Q000453:epidemiology* / Q000473:pathology; D018450:Disease Progression; D005215:Fasting / Q000097:blood; D005260:Female; D006442:Glycated Hemoglobin / Q000032:analysis*; D006801:Humans; D007558:Italy / Q000453:epidemiology; D016015:Logistic Models; D008297:Male; D015999:Multivariate Analysis; D016017:Odds Ratio; D011237:Predictive Value of Tests; D012307:Risk Factors; D012720:Severity of Illness Index
D001786:Blood Glucose; D006442:Glycated Hemoglobin