[Capillary HbA1c determination on type 2 diabetes patients in a primary health centre]

Assessment of Two Diabetes Point-of-care Analyzers Measuring Hemoglobin A1c in the Peruvian Amazon

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.

Assessment of Two Diabetes Point-of-care Analyzers Measuring Hemoglobin A1c in the Peruvian Amazon

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.

Verification of a novel point-of-care HbA1c device in real world clinical practice by comparison to three high performance liquid chromatography instruments

Introduction

A real world clinical study was designed and conducted to evaluate the performance of a novel point-of-care device for determination of glycated haemoglobin A_1c (HbA_1c), A1C EZ 2.0, in daily clinical practice.

Materials and methods

Five hundred and fourteen subjects were included in this study, and divided into three groups. HbA_1c was measured by A1C EZ 2.0 and three different high performance liquid chromatography (HPLC) devices: Bio-Rad Variant II Turbo, Tosoh HLC-723 G8 and Premier Hb9210 separately. Precision of A1C EZ 2.0 was also evaluated.

Results

Results obtained from A1C EZ 2.0 and all HPLC devices are correlated. Passing-Bablok regression analysis shows the equation of A1C EZ 2.0 results against the mean of HPLC devices with corresponding 95% confidence intervals (95% CI) for the intercept and slope is y = 0.10 (- 0.17 to 0.10) + 1.00 (1.00 to 1.04) x. Bland-Altman difference plot shows that the mean relative difference between A1C EZ 2.0 and Variant II Turbo, G8, Hb9210 and all HPLC results is 2.5%, 0.6%, 0.4% and 1.1%, respectively. In addition, 121 pairs of results determined by using both venous and capillary blood prove that the difference of two kinds of blood sample causes no notable variation when measured by A1C EZ 2.0. Precision study gives 2.3% and 1.9% of total coefficient of variation for normal and abnormal HbA_1c sample in A1C EZ 2.0.

Conclusions

HbA_1c values measured by A1C EZ 2.0 were in good accordance with the results obtained with the reference HPLC devices.

[Introduction of capillary glycosylated haemoglobin determination in a Primary Care Health Area: Multicentre study of the evolution of patients with type 2 diabetes mellitus]

PURPOSE

The aim of this study was to evaluate the efficiency of a joint intervention that included educational components, self-assessment, and information to optimise diabetes control through the introduction of instant capillary glycosylated haemoglobin (HbA1c) determination in Primary Care.

MATERIALS AND METHODS

A multicentre prospective descriptive study was carried out over 3years in 10Primary Care Centres of the Area VII Murcia East. At the end of the study there were 804 patients with type 2 diabetes (DM2). Patients were divided into 4 groups based on initial values of HbA1c, and if changes in their treatment were needed. HbA1c, body mass index, and blood pressure were monitored. A financial assessment was also performed on the impact of the implementation of a protocol to measure instant capillary RESULTS: A significant reduction was observed in HbA1c values. The initial HbA1c mean value was 7.4±1.4%, which decreased to a final value of 6.9±1.0% (P<.001). At the end of the study, 71.4% of patients included reached diabetic control objectives. In addition, the financial assessment demonstrated that the implementation of this diabetes control system led to a decrease of the 24.7% in spending on glucose strips after the first year of study in Area VII Murcia Health Service.

CONCLUSIONS

The introduction of capillary HbA1c determination in Primary Care has demonstrated to improve diabetes control and the efficiency of the health personnel. Furthermore, a reduction in the health costs of patients with DM2 was also shown.