Fasting blood glucose in determining the prevalence of diabetes in a large, homogeneous population of Caucasian middle-aged women

J Intern Med. 1995 Jun;237(6):537-41. doi: 10.1111/j.1365-2796.1995.tb00882.x.

Abstract

Objectives: To determine the usefulness of a single, fasting blood glucose (FBG) value in measuring the prevalence of diabetes mellitus in a large, homogeneous population.

Design: Fasting blood glucose and 2-h oral glucose tolerance test (OGTT) values were determined. Based on the results of the OGTT, the sensitivity and specificity of different cut-off levels of FBG for the diagnosis of diabetes were assessed. ROC (receiver operating characteristic) analysis was performed on the data.

Setting: A health screening unit at the University Hospital in Malmö, Sweden.

Subjects: A total of 1843 Caucasian women without known diabetes aged 55-57 years.

Results: The prevalence of previously undiagnosed diabetes was 3.9% and the prevalence of impaired glucose tolerance (IGT) was 27.9% using the WHO cut-off values for 2-h blood glucose values after an OGTT. With an FBG cut-off value of 6.7 mmol L-1, the sensitivity of a single FBG value was 36.6%. Reducing the cut-off value to 6.0 mmol L-1 increased the sensitivity to 53.4%. At a cut-off level of 4.8 mmol L-1, the sensitivity reached the high value of 85.9%, but the specificity was only 45% and the predictive value of a positive test as low as 5.9%. ROC analysis showed that the optimal cut-off value for FBG in this population was 5.3 mmol L-1, giving a sensitivity and specificity of 77% but a positive predictive value of only 11.9%.

Conclusions: This study has shown that in a large and homogeneous Caucasian population of women aged 55-57 years with a high prevalence of IGT, a single FBG value is not useful as a screening tool for diabetes mellitus.

MeSH terms

  • Blood Glucose* / metabolism
  • Diabetes Mellitus / diagnosis*
  • Diabetes Mellitus / epidemiology*
  • Diabetes Mellitus / ethnology
  • European Continental Ancestry Group*
  • Fasting
  • Female
  • Glucose Tolerance Test
  • Humans
  • Middle Aged
  • Predictive Value of Tests
  • Prevalence
  • Sweden / epidemiology

Substances

  • Blood Glucose