Diagnostic Accuracy and Feasibility of Point-Of-Care Glycosylated Hemoglobin Estimation in Field Conditions in India

Abstract

Background: Measurement of glycosylated hemoglobin (HbA1c) levels is standard of care in assessment of glycemic control among diabetes mellitus patients. Traditional high performance liquid chromatography (HPLC) based tests are expensive, need specialized equipment, and have a longer turn-around-time. Point-of-care tests to estimate HbA1c levels are now commercially available but with only limited studies from developed nations. We performed this study to understand diagnostic accuracy of two commercially available HbA1c point-of-care test. Methods: The study was conducted in an urban and a rural outpatient clinic in central India. We compared HbA1c estimated from two index tests (Hemocue Hb501, Sweden; SD Biosensor, South Korea) from capillary blood samples and compared it with HPLC, as a reference standard in an independent and a blinded manner. We estimated diagnostic accuracy of the index tests as compared to the reference standard. Results: The area under Reciever Operating Curve (ROC) for SDBiosensor device was 0.935 (95% CI = 0.886–0.983), and for HemocueHb501 device was 0.938 (95% CI = 0.893–0.984). A SDBiosensor device HbA1c value of above 7.0% = 53 mmol/mol (positive test) correctly predicted poor glycemic control 92% times (vs. 81.58% for HemocueHb501divice). A HemocueHb501device HbA1c value of less than 7.0% = 53 mmol/mol (negative test) correctly predicted optimal glycemic control 91% times (vs. 85% by SDBiosensor device). There were 4, and 11 device failures, and 14 and 12 test failures with SDBiosensor device and HemocueHb501 device respectively. Ambient air temperatures were no different for the test failure rates as compared to the test success events. Conclusion: Commercially available point-of-care tests evaluated in this study are comparable and an acceptable alternative to HPLC based measurements for assessment of glycemic control. Tests and device failure rates of both the index tests were similar.