title: Diabetes and abnormal glucose tolerance in subjects with tuberculosis in a South African urban center.
abstract: Primary health care clinics.
  
  
  
  To determine the prevalence of diabetes mellitus (DM) in tuberculosis (TB) patients using glycated haemoglobin (HbA1c), and to compare the performance of laboratory and point-of-care (POC) HbA1c measurement.
  
  
  
  This was a cross-sectional study of 325 patients. Screening was at POC using laboratory HbA1c methods; DM was confirmed by the oral glucose tolerance test (OGTT). Multivariate regression analysis was performed to determine predictors of HbA1c.
  
  
  
  Mean laboratory-derived HbA1c was significantly higher than mean POC HbA1c (P = 0.007). Of 83 subjects who underwent OGTT, 2 (2.4%) were diagnosed with DM, 3 (3.60%) with impaired fasting glucose and 15 (18.1%) with impaired glucose tolerance. Twelve (14.5%) had an HbA1c of 6.50% using POC HbA1c and 21 (25.3%) using laboratory HbA1c. In multivariate regression analysis, age and weight were positively associated with both laboratory and POC HBA1c, while duration of anti-tuberculosis treatment was negatively associated with both.
  
  
  
  Glucose and HbA1c levels fell with increased duration of anti-tuberculosis treatment, suggesting that the optimal time for DM screening in this population was at least 5 months after TB was first diagnosed. Our data suggest that the use of HbA1c is inappropriate for testing glycaemia in patients with TB.
authors.affiliation: Department of Chemical Pathology, National Health Laboratory Services, University of the Witwatersrand, Johannesburg, South Africa.
authors.forename: V
authors.initials: V
authors.lastname: Mcebula
authors.affiliation: Department of Chemical Pathology, National Health Laboratory Services, University of the Witwatersrand, Johannesburg, South Africa.
authors.forename: N J
authors.initials: NJ
authors.lastname: Crowther
authors.affiliation: Department of Chemical Pathology, National Health Laboratory Services, University of the Witwatersrand, Johannesburg, South Africa.
authors.forename: S E
authors.initials: SE
authors.lastname: Nagel
authors.affiliation: Department of Chemical Pathology, National Health Laboratory Services, University of the Witwatersrand, Johannesburg, South Africa, Department of Chemical Pathology, National Health Laboratory Services, University of the Witwatersrand, Johannesburg, South Africa.
authors.forename: J A
authors.initials: JA
authors.lastname: George
mesh_terms: D000328:Adult; D003430:Cross-Sectional Studies; D003920:Diabetes Mellitus / Q000175:diagnosis / Q000453:epidemiology*; D005260:Female; D018149:Glucose Intolerance / Q000453:epidemiology*; D005951:Glucose Tolerance Test; D006442:Glycated Hemoglobin / Q000032:analysis*; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D000067716:Point-of-Care Testing; D011320:Primary Health Care; D012044:Regression Analysis; D013019:South Africa; D014376:Tuberculosis / Q000453:epidemiology*; D019037:Urban Health Services
chemical_list: D006442:Glycated Hemoglobin; C517652:hemoglobin A1c protein, human