Continuous relationships between non-diabetic hyperglycaemia and both cardiovascular disease and all-cause mortality: the Australian Diabetes, Obesity, and Lifestyle (AusDiab) study.
OBJECTIVE
Hyperglycaemia is a risk factor for cardiovascular disease (CVD) and all-cause mortality in individuals without diabetes. We investigated: (1) whether the risk of all-cause and CVD mortality extended continuously throughout the range of fasting plasma glucose (FPG), 2 h plasma glucose (2hPG) and HbA(1c) values; and (2) the ability of these measures to improve risk prediction for mortality.


METHODS
Data on 10,026 people aged >or=25 years without diagnosed diabetes were obtained from the population-based Australian Diabetes, Obesity and Lifestyle study. Between 1999 and 2000, FPG, 2hPG and HbA(1c) were assessed and all-cause (332 deaths) and CVD (88 deaths) mortality were obtained after 7 years.


RESULTS
Both 2hPG and HbA(1c) exhibited linear relationships with all-cause and CVD mortality, whereas FPG showed J-shaped relationships. The adjusted HR (95% CI) for all-cause mortality per SD increase was 1.2 (1.1-1.3) for 2hPG and 1.1 (1.0-1.2) for HbA(1c). The HR for FPG <5.1 mmol/l (per SD decrease) was 2.0 (1.3-3.0); for FPG >or=5.1 mmol/l (per SD increase) the HR was 1.1 (1.0-1.2). Corresponding HRs for CVD mortality were 1.2 (1.0-1.4), 1.2 (1.0-1.3), 4.0 (2.1-7.6) and 1.3 (1.1-1.4). The discriminative ability of each measure was similar; no measure substantially improved individual risk identification over traditional risk factors.


CONCLUSIONS
In individuals without diagnosed diabetes, 2hPG and FPG, but not HbA(1c) were significant predictors of all-cause mortality, whereas all measures were significant predictors of CVD mortality. However, these glucose measures did not substantially improve individual risk identification.
Barr
E L M
EL
Baker IDI Heart and Diabetes Institute, 250 Kooyong Road, Caulfield, 3162, VIC, Australia. Elizabeth.Barr@bakeridi.edu.au
Boyko
E J
EJ
Zimmet
P Z
PZ
Wolfe
R
R
Tonkin
A M
AM
Shaw
J E
JE
D001315:Australia / Q000453:epidemiology; D001786:Blood Glucose / Q000378:metabolism; D001794:Blood Pressure; D002318:Cardiovascular Diseases / Q000453:epidemiology* / Q000401:mortality; D003920:Diabetes Mellitus / Q000097:blood / Q000453:epidemiology* / Q000401:mortality; D005260:Female; D005500:Follow-Up Studies; D006442:Glycated Hemoglobin / Q000032:analysis; D006339:Heart Rate; D006801:Humans; D006943:Hyperglycemia / Q000453:epidemiology* / Q000401:mortality; D008019:Life Style; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000453:epidemiology* / Q000401:mortality; D016016:Proportional Hazards Models; D014280:Triglycerides / Q000097:blood; D049629:Waist-Hip Ratio
D001786:Blood Glucose; D006442:Glycated Hemoglobin; D014280:Triglycerides