The Evolution of Diabetes Technology - Options Towards Personalized Care

Advances in diabetes technology, especially in the last few decades, have transformed our ability to deliver care to persons with diabetes (PWD). Developments in glucose monitoring, especially continuous glucose monitoring systems (CGM), have revolutionized diabetes care and empowered our patients to manage their disease. CGM has also played an integral role in advancing automated insulin delivery systems. Currently available and upcoming advanced hybrid-closed loop systems aim to decrease patient involvement and are approaching the functionality of a fully automated artificial pancreas. Other advances, such as smart insulin pens and daily patch pumps, offer more options for patients and require less complicated and costly technology. Evidence to support the role of diabetes technology is growing, and PWD and clinicians must choose the right type of technology with a personalized strategy to manage diabetes effectively. Here, we review currently available diabetes technologies, summarize their individual features and highlight key patient factors to consider when creating a personalized treatment plan. We also address current challenges and barriers to the adoption of diabetes technologies.

Commutability of external quality assessment materials for point-of-care glucose testing using the Clinical and Laboratory Standards Institute and International Federation of Clinical Chemistry approaches

Objectives

The aim of this study was to assess the commutability of three external quality assessment (EQA) materials for point‐of‐care (POC) glucose testing using two approaches, to identify suitable EQA materials to evaluate and monitor the quality of POC testing.

Methods

Commercial control materials (CCMs), pooled human serum samples (PHSs), and homemade human whole‐blood samples (HWBs) were measured along with 33 individual clinical samples using five POC instruments and a Hitachi 7600 analyzer. Data were analyzed by Deming regression analysis with a 95% prediction interval as described in Clinical and Laboratory Standards Institute (CLSI) EP30‐A, and by difference in bias analysis as described by the International Federation of Clinical Chemistry (IFCC) Working Group on Commutability.

Results

Using the CLSI approach, HWBs, CCMs, and PHSs were commutable with five, one, and two instruments, respectively. With the IFCC approach, HWBs were commutable with two instruments, while CCMs and PHSs were largely inconclusive or non‐commutable on five instruments.

Conclusions

HWBs were commutable on all instruments by the CLSI approach and may be a suitable EQA material for POC testing. Although some results differed between the IFCC and CLSI approaches, both indicated that HWBs were far superior to CCMs and PHSs in commutability.

Historical perspectives in clinical pathology: a history of glucose measurement

This is the second in the series of historical articles dealing with developments in clinical pathology. As one of the most commonly measured analytes in pathology, the assessment of glucose dates back to the time of the ancient Egyptians. It was only in the 19th century that advances in chemistry led to the identification of the sugar in urine being glucose. The following century witnessed the development of more chemical and enzymatic methods which became incorporated into the modern analysers and point-of-care instruments which are as ubiquitous as the modern day cellphones. Tracking the milestones in these developments shows the striking paradigms and the many parallels in the development of other clinical chemistry methods.

Glucose meters - fit for clinical purpose

Glucose meters have improved considerably since they were first introduced in 1960, but many questions are being asked about their accuracy and reliability in certain clinical situations. These questions have arisen because of the widespread use of these meters into clinical areas they have not been designed for such as critical care. The lack of understanding by some health professionals on factors that affect glucose results, such as sample type, glucose test strip methodologic limitations, calibration to recognized reference methods, and interferences, leads to misleading results that may affect patient care. Much debate continues on the quality specifications for glucose meters. Because there is an extensive use of these meters in different clinical scenarios, the setting of quality specifications will remain a challenge for regulatory and professional organizations. In this article, we have attempted to collect and provide relevant information addressing the limitations above. Pivotal to obtaining the best quality of results is education, particularly for diabetic patients monitoring their glucose. The International Federation of Clinical Chemistry and Laboratory Medicine through its Point-of-Care Testing Task Force and its Working Group on Glucose Point-of-Care Testing is actively working toward improving the quality of glucose results by improving education and working with the industry to improve strip performance and work toward the better standardization of strips.

Analytical performance of glucose monitoring systems at different blood glucose ranges and analysis of outliers in a clinical setting

We investigated the analytical accuracy of 27 glucose monitoring systems (GMS) in a clinical setting, using the new ISO accuracy limits. In addition to measuring accuracy at blood glucose (BG) levels < 100 mg/dl and > 100 mg/dl, we also analyzed devices performance with respect to these criteria at 5 specific BG level ranges, making it possible to further differentiate between devices with regard to overall performance. Carbohydrate meals and insulin injections were used to induce an increase or decrease in BG levels in 37 insulin-dependent patients. Capillary blood samples were collected at 10-minute intervals, and BG levels determined simultaneously using GMS and a laboratory-based method. Results obtained via both methods were analyzed according to the new ISO criteria. Only 12 of 27 devices tested met overall requirements of the new ISO accuracy limits. When accuracy was assessed at BG levels < 100 mg/dl and > 100 mg/dl, criteria were met by 14 and 13 devices, respectively. A more detailed analysis involving 5 different BG level ranges revealed that 13 (48.1%) devices met the required criteria at BG levels between 50 and 150 mg/dl, whereas 19 (70.3%) met these criteria at BG levels above 250 mg/dl. The overall frequency of outliers was low. The assessment of analytical accuracy of GMS at a number of BG level ranges made it possible to further differentiate between devices with regard to overall performance, a process that is of particular importance given the user-centered nature of the devices' intended use.

Transitioning to a national (New Zealand) sole supply scheme for glucose meters: lessons learned, problems yet to be solved

This case study describes the clinical impact of moving to a single brand of glucose test strips. In 2013 the New Zealand public health system completed a move to procure test strips at a significant discount. The associated direct savings is estimated at around 40% of the total glucose strip budget. Half the local diabetes population undertake glucose monitoring using government-funded diabetes supplies. These patients no longer have a choice of brand of meters and strips. Although the majority of patients adapted well to this change, a small percentage did not. Also, some consumers expressed concerns about analytical performance of the new strips, when used in everyday life. A pragmatic postmarketing surveillance system, designed with consumer input, may help address these residual concerns.

Considerations for an institution for evaluation of diabetes technology devices to improve their quality in the European Union

All medical devices used for self-monitoring of blood glucose (BG), insulin injection, continuous subcutaneous insulin infusion, and continuous glucose monitoring in the European Union (EU) must have a Communauté Européenne (CE) mark. However, the approval process for obtaining this mark is different from that used by the European Medicines Agency in the EU for drugs or by the Food and Drug Administration in the United States for such medical and in vitro diagnostic devices. The notified bodies involved in the CE mark process perform this evaluation in cooperation with the manufacturers. They have only limited diabetes know-how; they have to handle all kinds of medical devices. There are devices for therapy on the market in the EU (i.e., they have market approval) that do not fulfill quality requirements, as indicated, for example, in the international norm ISO 15197 for BG test systems. Evaluation of the performance of such systems is usually provided by the manufacturers. What is missing in the EU is an independent institution that performs regular and critical evaluation of the quality of devices used for diabetes therapy before and also after their market approval. The work of such an institution would focus on BG test systems (these represent two-thirds of the market of medical devices for diabetes treatment) but would also evaluate the performance of other devices. It has to be clarified what legal framework is required for such an institution and how it can be financed; probably this can be done in a shared manner by the manufacturers of such devices and the health insurance companies. Positive evaluation results should be a prerequisite prior to any reimbursement for such devices.

Accuracy in blood glucose measurement: what will a tightening of requirements yield?

Nowadays, almost all persons with diabetes--at least those using antidiabetic drug therapy--use one of a plethora of meters commercially available for self-monitoring of blood glucose. The accuracy of blood glucose (BG) measurement using these meters has been presumed to be adequate; that is, the accuracy of these devices was not usually questioned until recently. Health authorities in the United States (Food and Drug Administration) and in other countries are currently endeavoring to tighten the requirements for the accuracy of these meters above the level that is currently stated in the standard ISO 15197. At first glance, this does not appear to be a problem and is hardly worth further consideration, but a closer look reveals a considerable range of critical aspects that will be discussed in this commentary. In summary, one could say that as a result of modern production methods and ongoing technical advances, the demands placed on the quality of measurement results obtained with BG meters can be increased to a certain degree. One should also take into consideration that the system accuracy (which covers many more aspects as the analytical accuracy) required to make correct therapeutical decisions certainly varies for different types of therapy. At the end, in addition to analytical accuracy, thorough and systematic training of patients and regular refresher training is important to minimize errors. Only under such circumstances will patients make appropriate therapeutic interventions to optimize and maintain metabolic control.

Towards more complete specifications for acceptable analytical performance - a plea for error grid analysis

Abstract We examine limitations of common analytical performance specifications for quantitative assays. Specifications can be either clinical or regulatory. Problems with current specifications include specifying limits for only 95% of the results, having only one set of limits that demarcate no harm from minor harm, using incomplete models for total error, not accounting for the potential of user error, and not supplying sufficient protocol requirements. Error grids are recommended to address these problems as error grids account for 100% of the data and stratify errors into different severity categories. Total error estimation from a method comparison can be used to estimate the inner region of an error grid, but the outer region needs to be addressed using risk management techniques. The risk management steps, foreign to many in laboratory medicine, are outlined.