Point-of-care testing of HbA1c and blood glucose in a remote Aboriginal Australian community.

OBJECTIVES To assess the accuracy of point-of-care (POC) measurements of capillary blood glucose and glycosylated haemoglobin (HbA(1c)) levels in a remote Aboriginal community with high diabetes prevalence. DESIGN Cross-sectional study comparing POC capillary glucose and HbA(1c) results with those from corresponding venous samples measured in a reference laboratory. PARTICIPANTS AND SETTING 152 residents aged 11-76 years (representing 76% of population aged over 11 years) had POC glucose measurement in November 2003; 88 with POC glucose level > or = 5.0 mmol/L, or self-reported diabetes, had POC HbA(1c) and laboratory glucose and HbA(1c) measurements. MAIN OUTCOME MEASURES POC fasting capillary levels of glucose (HemoCue Glucose 201 analyser, Medipac Scientific, Sydney) and HbA(1c) (DCA 2000+ analyser, Bayer Australia, Melbourne); correlation and mean difference between capillary POC and venous blood laboratory measurements of glucose and HbA(1c). RESULTS Mean and median POC capillary glucose levels were 7.99 mmol/L and 6.25 mmol/L, respectively, while mean and median laboratory venous plasma glucose concentrations were 7.63 mmol/L and 5.35 mmol/L. Values for POC capillary HbA(1c) and laboratory HbA(1c) were identical: mean, 7.06%; and median, 6.0%. The correlation coefficient r for POC and laboratory results was 0.98 for glucose and 0.99 for HbA(1c). The mean difference in results was 0.36 mmol/L for glucose (95% CI, 0.13-0.62; limits of agreement [LOA], - 2.07 to 2.79 mmol/L; P = 0.007) and < 0.01% for HbA(1c) (95% CI, - 0.07% to 0.07%; LOA, - 0.66% to 0.66%; P = 0.95), respectively. CONCLUSIONS POC capillary HbA(1c) testing, in particular, offers an accurate, practical, community-friendly way of monitoring diabetes in rural and remote clinical settings. POC capillary glucose results should be confirmed by a laboratory test of venous plasma if the results are likely to significantly influence clinical decisions.