Diabetes Care, Vol 18, Issue 4 463-466, Copyright © 1995 by American Diabetes Association
Screening for diabetes mellitus in adults. The utility of random capillary blood glucose measurements
MM Engelgau, TJ Thompson, PJ Smith, WH Herman, RE Aubert, EW Gunter, SF Wetterhall, ES Sous and MA Ali
Division of Diabetes Translation, Centers for Disease Control and Prevention, Atlanta, GA 30341-3724, USA.
OBJECTIVE--Because half of the people with non-insulin-dependent diabetes
mellitus (NIDDM) are undiagnosed and because near-normal glycemic control
can prevent diabetic complications, we evaluated the use of field-based
random capillary blood glucose measurement as a screening test for NIDDM.
RESEARCH DESIGN AND METHODS--A cross-sectional sample of 828 Egyptians >
or = 20 years of age underwent both a random capillary blood glucose
measurement performed with a portable reflectance meter in the field and an
oral glucose tolerance test in the laboratory. The sensitivity and
specificity of random capillary blood glucose measurements in predicting
the presence of NIDDM were evaluated. RESULTS--Multivariate analyses showed
that the screening test performed better when subjects had eaten shortly
before the test (area under receiver operating characteristic curve, 0.87
for a 1-h postprandial period compared with 0.69 for an 8-h postprandial
period) and that the optimal capillary blood glucose cutoff points to
define a positive test increased with age. For a postprandial period of 1
h, cutoff points of 115 mg/dl for individuals 30 years of age and 140 mg/dl
for those 75 years of age yielded similar performance characteristics
(sensitivity 82% and specificity 78% for those 30 years old; sensitivity
81% and specificity 80% for those 75 years old). CONCLUSIONS--Adjusting
random capillary blood glucose measurements for the postprandial period and
using age-specific cutoff point values can improve performance of the
screening test.