Changes in glycaemic control and risk of coronary artery disease in type 1 diabetes mellitus: findings from the Pittsburgh Epidemiology of Diabetes Complications Study (EDC).
OBJECTIVE
To complete a comparative analysis of studies that have examined the relationship between glycaemia and cardiovascular disease (CVD)/coronary artery disease (CAD) and perform a prospective analysis of the effect of change in glycosylated Hb level on CAD risk in the Pittsburgh Epidemiology of Diabetes Complications Study (EDC) of childhood-onset type 1 diabetes mellitus (n = 469) over 16 years of two yearly follow-up.


METHODS
Measured values for HbA(1) and HbA(1c) from the EDC were converted to the DCCT-standard HbA(1c) for change analyses and the change in HbA(1c) was calculated (final HbA(1c) minus baseline HbA(1c)). CAD was defined as EDC-diagnosed angina, myocardial infarction, ischaemia, revascularisation or fatal CAD after medical record review.


RESULTS
The comparative analysis suggested that glycaemia may have a stronger effect on CAD in patients without, than in those with, albuminuria. In EDC, the change in HbA(1c) differed significantly between CAD cases (+0.62 +/- 1.8%) and non-cases (-0.09 +/- 1.9%) and was an independent predictor of CAD.


CONCLUSIONS
Discrepant study results regarding the relationship of glycaemia with CVD/CAD may, in part, be related to the prevalence of renal disease. Measures of HbA(1c) change over time show a stronger association with CAD than baseline values.
Prince
C T
CT
Department of Epidemiology, University of Pittsburgh Graduate School of Public Health, 3512 Fifth Avenue, Second Floor, Pittsburgh, PA 15213, USA.
Becker
D J
DJ
Costacou
T
T
Miller
R G
RG
Orchard
T J
TJ
D000328:Adult; D001786:Blood Glucose / Q000378:metabolism*; D015992:Body Mass Index; D003327:Coronary Disease / Q000453:epidemiology*; D003922:Diabetes Mellitus, Type 1 / Q000097:blood* / Q000150:complications*; D003925:Diabetic Angiopathies / Q000453:epidemiology*; D005260:Female; D006442:Glycated Hemoglobin / Q000378:metabolism; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D010414:Pennsylvania; D012307:Risk Factors
D001786:Blood Glucose; D006442:Glycated Hemoglobin