Abstract
BACKGROUND: With an estimated 174 million undiagnosed cases of diabetes mellitus worldwide and 80% of them occurring in low- and middle-income countries an effective point-of-care diagnostic tool is key to fighting this global epidemic. Glycated hemoglobin has become a reliable biomarker for the diagnosis and prognosis of diabetes. OBJECTIVE: We assessed two point-of-care (POC) analyzers in multi-ethnic communities of the Amazon Rainforest in Peru where laboratory-based glycated hemoglobin (HbA1c) testing is not available. METHODS: 203 venous blood samples were tested for HbA1c by Afinion and DCA Vantage analyzers as well as a Premier Hb9210 high-performance liquid chromatography (HPLC) method as the reference standard. The coefficient of variation (CV) of each device was calculated to assess assay imprecision. Bland-Altman plots were used to assess bias. Ambient temperature, humidity, and barometric pressure were also evaluated for their effect on HbA1c results using multivariate regression. FINDINGS: There was a wide range of HbA1c for participants based on the HPLC test: 4.4-9.0% (25-75 mmol/mol). The CV for the Afinion was 1.75%, and 4.01% for Vantage. The Afinion generated higher HbA1c results than the HPLC (mean difference = +0.56% [+6 mmol/mol]; p < 0.001), as did the DCA Vantage (mean difference = +0.32% [4 mmol/mol] p < 0.001). Temperature and humidity were not related to HbA1c; however, barometric pressure was associated with HPLC HbA1c results for the Afinion. CONCLUSIONS: Imprecision and bias were not low enough to recommend either POC analyzer for HbA1c determinations in this setting.