Plasma glucose reference interval in a low-risk population. 2. Impact of the new WHO and ADA recommendations on the diagnosis of diabetes mellitus.
The aim of the study was to establish a reference interval of fasting venous plasma glucose (FPG) from healthy individuals. A prospective modified cross-sectional population-based study was made with random selection of 2100 persons in age-stratified groups > or = 18 years identified from the local Personal Identification Register. The invitation was accepted by 755 persons, of which 726 aged 18-92 years were eligible. They did not have a diabetes diagnosis, were non-pregnant and capable of fasting for 8 h. All participants filled in a questionnaire on medical risk factors. Blood for the FPG and haemoglobin Alc (HbAlc) measurements was drawn in accordance with a standardized procedure. A total of 302 participants carried diabetes risk indicators and were ruled out. The FPG concentrations in the remaining low-risk population (n=424) was ln Gaussian distributed. The FPG 97.50 centile in this group was 6.4 mmol/L (95% CI: 6.3-6.5 mmol/L), in contrast to the WHO and ADA theoretical limit of 6.1 mmol/L. Their diagnostic decision limit of 7.0 mmol/L FPG corresponded to the 99.86 centile of the FPG reference distribution (95% CI: 6.8-7.1). Subclassification of the reference population showed increasing FPG with increasing BMI and age and was higher in men than in women. The study determined the FPG 95% interfractile reference interval in a healthy population. The interval in glucose concentration between the 97.5 centile of the reference interval and the ADA-WHO diagnostic limit is very narrow. The clinical application of the diagnostic discriminator and the interpretation of the WHO-ADA grey zone from 6.1 to 7.0 mmol/L FPG may consequently be biased because of poorly defined limits and influence from BMI, age and gender.
Jørgensen
L G
LG
Clinical Biochemistry, The Laboratory Center, Vejle County Hospital, Denmark. lgmj@ofir.dk
Stahl
M
M
Brandslund
I
I
Hyltoft Petersen
P
P
Borch-Johnsen
K
K
de Fine Olivarius
N
N
D000293:Adolescent; D000328:Adult; D000368:Aged; D001786:Blood Glucose / Q000032:analysis*; D002624:Chemistry, Clinical / Q000592:standards*; D003430:Cross-Sectional Studies; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000175:diagnosis* / Q000453:epidemiology; D005260:Female; D017408:Guidelines as Topic; D006801:Humans; D008297:Male; D008875:Middle Aged; D016011:Normal Distribution; D011446:Prospective Studies; D012016:Reference Values; D012307:Risk Factors; D012955:Societies, Medical / Q000592:standards; D014944:World Health Organization
D001786:Blood Glucose