Time filter

Source Type

San Mateo, CA, United States

Klonoff D.C.,Mills Peninsula Health Services | Reyes J.S.,Diabetes Technology Society
Journal of Diabetes Science and Technology | Year: 2013

Blood glucose monitors (BGMs) are approved by regulatory agencies based on their performance during strict testing conducted by their manufacturers. However, after approval, there is uncertainty whether BGMs maintain the accuracy levels that were achieved in the initial data. The availability of inaccurate BGM systems pose a public health problem because their readings serve as a basis for treatment decisions that can be incorrect. Several articles have concluded that BGMs in the marketplace may not consistently provide accurate results in accordance with the regulatory standards that led to approval. To address this growing concern, Diabetes Technology Society organized and conducted a 1-day public meeting on May 21, 2013, in Arlington, VA, presided by its president, David Klonof, M.D., FACP, Fellow AIMBE, to determine whether BGMs on the market meet regulatory standards. The meeting consisted of four sessions in which Food and Drug Administration diabetes experts as well as leading academic clinicians and clinical chemists participated: (1) How is BGM performance determined? (2) Do approved BGMs perform according to International Organization for Standardization standards? (3) How do approved BGMs perform when used by patients and health care professionals? (4) What could be the consequence of poor BGM performance? © Diabetes Technology Society.

Klonoff D.C.,Mills Peninsula Health Services
Journal of Diabetes Science and Technology | Year: 2012

Fluorescence represents a promising alternative technology to electrochemistry and spectroscopy for accurate analysis of glucose in diabetes; however, no implanted fluorescence glucose assay is currently commercially available. The method depends on the principle of fluorescence, which is the emission of light by a substance after absorbing light. A fluorophore is a molecule that will absorb energy of a specific wavelength and reemit energy at a different wavelength. A fluorescence glucose-sensing molecule can be constructed to increase or decrease in fluorescence from baseline according to the ambient concentration of glucose. A quantum dot is a semiconductor crystal that can serve as a sensor by fluorescing at a desired wavelength or color, depending on the crystal size and materials used. If receptor molecules for glucose can be adsorbed to single-wall carbon nanotubules, then the resulting binding of glucose to these receptors will alter the nanotubes' fluorescence. Fluorescence glucose sensors can provide a continuous glucose reading by being embedded into removable wire-shaped subcutaneous or intravenous catheters as well as other types of implanted structures, such as capsules, microcapsules, microbeads, nano-optodes, or capillary tubes. Fluorescence glucose-sensing methods, which are under development, ofer four potential advantages over commercially used continuous glucose monitoring technologies: (1) greater sensitivity to low concentrations of glucose, (2) the possibility of constructing sensors that operate most accurately in the hypoglycemic range by using binding proteins with disassociation constants in this range, (3) less need to recalibrate in response to local tissue reactions around the sensor, and (4) no need to implant either a transmitter or a power source for wireless communication of glucose data. Fluorescence glucose sensors also have four significant disadvantages compared with commercially used continuous glucose monitoring technologies: (1) a damaging foreign body response; (2) a sensitivity to local pH and/or oxygen, which can afect the dye response; (3) potential toxicity of implanted dyes, especially if the implanted fluorophore cannot be fully removed; and (4) the necessity of always carrying a dedicated light source to interrogate the implanted sensor. Fluorescence sensing is a promising method for measuring glucose continuously, especially in the hypoglycemic range. If currently vexing technical and engineering and biocompatibility problems can be overcome, then this approach could lead to a new family of continuous glucose monitors. © Diabetes Technology Society.

Klonoff D.C.,Mills Peninsula Health Services
Journal of Diabetes Science and Technology | Year: 2015

Precision medicine is a modern concept that has been used since 2011 to describe tailored accurate medical treatments selected according to individual characteristics of each patient. Each patient's disease is analyzed according to molecular data, genomics, and systems biology in this model to establish the patient's disease process at the molecular level and select appropriate treatments. The patient's response is then closely monitored with direct or surrogate measures such as biomarkers, and the treatments can then be adapted according to the patient's response. The combination of traditional gross and microscopic metrics combined with molecular profiling is precision medicine. © 2015 Diabetes Technology Society.

Klonoff D.C.,Mills Peninsula Health Services
Journal of Diabetes Science and Technology | Year: 2013

mHealth is an emerging concept in health care and uses mobile communications devices for health services and information. Mobile phones, patient monitoring devices, tablets, personal digital assistants, and other wireless devices can be part of mHealth systems. With mHealth systems, glucose data can now be automatically collected, transmitted, aggregated with other physiologic data, analyzed, stored, and presented as actionable information. mHealth systems use mobile decision support software applications (or apps) to assist or direct health care professionals to make decisions, or they can assist or direct patients to make decisions without waiting for input from a clinician. With real-time decision support for patients, appropriate actions can be taken in real time without waiting to see a clinician. Decisions can be personalized if individual treatment goals and personal preferences for treatment are inputted into an app. Few mHealth apps for diabetes have been rigorously tested. Outcome studies of the use of mHealth for diabetes from the literature have shown the potential for benefits, but higher-quality studies are needed. Regulatory approval of mHealth products will require demonstration of safety and efectiveness, especially where information and trends are not just presented to patients, but used to make treatment recommendations. Three additional hurdles must be overcome to facilitate widespread adoption of this technology, including demonstration of the following: (1) privacy to satisfy regulators, (2) clinical benefit to satisfy clinicians, and (3) economic benefit to satisfy payers. mHealth for diabetes is making rapid strides and is expected to be a transforming technology that will be the next big thing. © Diabetes Technology Society.

Garg S.,University of Colorado at Denver | Brazg R.L.,Rainier Clinical Research Center | Bailey T.S.,AMCR Institute Inc. | Buckingham B.A.,Stanford University | And 5 more authors.
Diabetes Technology and Therapeutics | Year: 2012

Background: The efficacy of automatic suspension of insulin delivery in induced hypoglycemia among subjects with type 1 diabetes was evaluated. Subjects and Methods: In this randomized crossover study, subjects used a sensor-augmented insulin pump system with a low glucose suspend (LGS) feature that automatically stops insulin delivery for 2 h following a sensor glucose (SG) value ≤70 mg/dL. Subjects fasted overnight and exercised until their plasma glucose (measured with the YSI 2300 STAT Plus™ glucose and lactate analyzer [YSI Life Sciences, Yellow Springs, OH]) value reached ≤85 mg/dL on different occasions separated by washout periods lasting 3-10 days. Exercise sessions were done with the LGS feature turned on (LGS-On) or with continued insulin delivery regardless of SG value (LGS-Off). The order of LGS-On and LGS-Off sessions was randomly assigned. YSI glucose data were used to compare the duration and severity of hypoglycemia from successful LGS-On and LGS-Off sessions and to estimate the risk of rebound hyperglycemia after pump suspension. Results: Fifty subjects attempted 134 sessions, 98 of which were successful. The mean±SD hypoglycemia duration was less during LGS-On than during LGS-Off sessions (138.5±76.68 vs. 170.7±75.91 min, P=0.006). During LGS-On compared with LGS-Off sessions, mean nadir YSI glucose was higher (59.5±5.72 vs. 57.6±5.69 mg/dL, P=0.015), as was mean end-observation YSI glucose (91.4±41.84 vs. 66.2±13.48 mg/dL, P<0.001). Most (53.2%) end-observation YSI glucose values in LGS-On sessions were in the 70-180 mg/dL range, and none was >250 mg/dL. Conclusions: Automatic suspension of insulin delivery significantly reduced the duration and severity of induced hypoglycemia without causing rebound hyperglycemia. © 2012, Mary Ann Liebert, Inc.

Discover hidden collaborations