Challenges for the implementation of the in-vitro diagnostics regulations in the light of â??real-lifeâ?? performance of blood glucose self-monitoring devices

Abstract

Objective: Accurate and reliable blood glucose monitoring devices (BGMDs) are required for adequate self-monitoring and management for people suffering from diabetes mellitus. To ensure a high level of safety for patients and users of in vitro diagnostic devices, an updated In Vitro Diagnostic Regulation (IVDR 2017/746) has been published, including new safety and performance prerequisites. However, BGMD accuracy may be limited by certain ‘real-life’ environmental factors, which should be respected in the performance evaluation. Methods: The temperature-and humidity-dependent performance of 4 different BGMD using up to 440 capillary blood samples was determined. BGMDs with associated test strips were stored at 15°C, 25°C and 35°C resp. at a relative humidity of 40% and 80% in order to imitate potential ‘real-life’ performance settings. Glucose measurements were compared to blood glucose values determined using standardized Laboratory equipment and were analyzed based on the ISO 15197:2013 system accuracy criteria. Results: Two out of three BGMDs provided consistent results across temperature ranges based on the medical threshold of a mean glucose change less than 15 mg/dl, although blood glucose difference of up to 96 mg/dl was found at an individual patient level after pairwise temperature comparison. For one device up to 31.2% of patients’ values were outside the defined limits when comparing 15o C to 35o C. Changes in humidity levels did not significantly influence the mean values across the BGMDs, although high deviations were observed at patients’ individual glucose levels. Conclusion: Moderate temperature and humidity changes can affect the accuracy of point-ofcare devices to a profound extent at an individual patient level. These ‘real-life’ environmental factors need to be included in the performance evaluation as required in the IVDR 2017/746 in order to provide a solid testing system for novel point-of-care-devices.