Comparison of fasting plasma glucose and haemoglobin A1c point-of-care tests in screening for diabetes and abnormal glucose regulation in a rural low income setting.
OBJECTIVE
Glycated haemoglobin (HbA1C) has been suggested to replace glucose tests in identifying diabetes and pre-diabetes. We assessed agreement between fasting plasma glucose (FPG) and HbA1C rapid tests in classifying abnormal glucose regulation (AGR), and their utility for preventive screening in rural Africa.


METHODS
A population-based survey of 795 people aged 35-60 years was conducted in a mainly rural district in Uganda. FPG was measured using On-Call® Plus glucometers, and classified using World Health Organization (WHO) and American Diabetes Association (ADA) criteria. HbA1C was measured using A1cNow® kits and classified using ADA criteria. Body mass index and blood pressure were measured. Percentage agreement between the two tests was computed.


RESULTS
Using HbA1C, 11.3% of participants had diabetes compared with 4.8% for FPG. Prevalence of HbA1C-defined pre-diabetes (26.4%) was 1.2 times and 2.5 times higher than FPG-defined pre-diabetes using ADA (21.8%) and WHO (10.1%) criteria, respectively. With FPG as the reference, agreement between FPG and HbA1C in classifying diabetes status was moderate (Kappa=22.9; Area Under the Curve (AUC)=75%), while that for AGR was low (Kappa=11.0; AUC=59%). However, agreement was high (over 90%) among negative tests and among participants with risk factors for type 2 diabetes (obesity, overweight or hypertension). HbA1C had more procedural challenges than FPG.


CONCLUSIONS
Although low in the general sample, agreement between HbA1C and FPG is excellent among persons who test negative with either test. A single test can therefore identify the majority at lower risk for type 2 diabetes. Nurses if trained can conduct these tests.
Department of Epidemiology, Biostatistics, Makerere University School of Public Health, Kampala, Uganda; Department of Public Health Sciences, Karolinska Institutet, Stockholm, Sweden. Electronic address: wromay2000@yahoo.co.uk.
Roy William
RW
Mayega
Department of Epidemiology, Biostatistics, Makerere University School of Public Health, Kampala, Uganda.
David
D
Guwatudde
Department of Epidemiology, Biostatistics, Makerere University School of Public Health, Kampala, Uganda.
Fredrick Edward
FE
Makumbi
Department of Internal Medicine, Mulago National Referral and Hospital, Kampala, Uganda.
Frederick Nelson
FN
Nakwagala
Department of Public Health Sciences, Karolinska Institutet, Stockholm, Sweden; Department of Health Policy, Planning and Management, Makerere University School of Public Health, Kampala, Uganda; International Maternal and Child Health Unit, Uppsala University, Uppsala, Sweden.
Stefan
S
Peterson
Department of Public Health Sciences, Karolinska Institutet, Stockholm, Sweden; Medical Management Centre (MMC), Department of Learning, Informatics, Management and Ethics (LIME), Karolinska Institutet, Stockholm, Sweden.
Göran
G
Tomson
Department of Molecular Medicine and Surgery, Endocrine and Diabetes Unit, Karolinska Institutet, Stockholm, Sweden.
Claes-Göran
CG
Ostenson
D000328:Adult; D001786:Blood Glucose / Q000378:metabolism*; D003924:Diabetes Mellitus, Type 2 / Q000097:blood* / Q000453:epidemiology; D005215:Fasting / Q000097:blood*; D005260:Female; D005951:Glucose Tolerance Test; D006442:Glycated Hemoglobin; D006801:Humans; D008297:Male; D008875:Middle Aged; D011203:Poverty; D011236:Prediabetic State / Q000097:blood* / Q000453:epidemiology; D015995:Prevalence; D011498:Protein Precursors / Q000097:blood*; D012307:Risk Factors; D012424:Rural Population; D014454:Uganda / Q000453:epidemiology
D001786:Blood Glucose; D006442:Glycated Hemoglobin; D011498:Protein Precursors; C040839:pre-hemoglobin A, glycosylated
Abnormal glucose regulation; Diabetes; Early detection; Fasting plasma glucose; Haemoglobin A(1C); Percentage agreement