ORLANDO (EGMN)—Progress towards an “artificial pancreas” for automatically controlling glucose levels in people with diabetes is happening in incremental steps that will start by minimizing hypoglycemic and hyperglycemic excursions.

“The artificial pancreas is not immediately going to be a system that you immediately plug on and walk away from your diabetes .... This is going to be an evolutionary, iterative process,” said Aaron J. Kowalski, at the annual meeting of the American Diabetes Association June 27. Dr. Kowalski is the assistant vice president for glucose control research at the Juvenile Diabetes Research Foundation. The foundation is funding much of the research into the development of “closed-loop” insulin delivery systems via its Artificial Pancreas Project.

Current areas of research focus include systems that would minimize hypo- and hyperglycemia, including a pump shut-off system that predicts impending nocturnal hypoglycemia and suspends delivery for up to 2 hours. The Medtronic Veo insulin pump that already contains such a mechanism is available in the United Kingdom but not the United States due to regulatory issues, Dr. Kowalski noted during a symposium.

Overnight closed-loop control is already possible with currently available technology, while improved sensors and insulin formulations will ultimately be needed in order to create a fully automated system that is envisioned as including a bihormonal system with glucagon as well as insulin, he said.

Dr. Roman Hovorka, of the Institute of Metabolic Science and the Department of Pediatrics at the University of Cambridge, U.K., presented new data on use of closed-loop overnight glucose control using currently-available insulin pumps and sensors along with an algorithm created by his team that utilizes adaptive model-predictive control in 17 children and 24 adults with type 1 diabetes.

Over 57 nights with the closed loop, the patients spent an average of 77% of the time in the target glucose range of 71-145 mg/dL, compared with just 47% of 45 nights with insulin pump therapy that did not use a closed-loop system. Similar benefit was seen in both the adults and the children, Dr. Hovorka said.

Marilyn Ritholz, Ph.D., a psychologist at the Joslin Diabetes Center, Boston, presented new qualitative data on attitudes toward the use of continuous glucose monitors in a focus group of 20 adults with type 1 diabetes who had participated in a JDRF-sponsored trial of the efficacy of CGM.

In semi-structured interviews, patients who had more success using CGM tended to use a problem-solving approach and used retrospective data to try and identify patterns, rather than simply relying on the minute-by-minute updates. Support from spouses and other loved ones was also important to achieving good results. On the other hand, patients who tended to react emotionally to the CGM readings and alarms were less likely to be successful, as were those whose spouses were disinterested or unsupportive.

And, while body image perception did not appear to predict success, certain themes emerged in that area that merit further exploration. From the patient’s perspective, “CGM needs to become a personal accessory and not a medical device,” Dr. Ritholz commented.

Dr. Kowalski and Dr. Ritholz stated that they have no conflicts of interest. Dr. Hovorka is on the advisory Panel for Animas, receives research support from MiniMed Medtronic, Abbott Diabetes Care, and Smiths Medical, and is on the speaker’s bureau for LifeScan, MiniMed Medtronic, Braun, and Novo Nordisk. He also receives license fees from Becton Dickinson.

Copyright (c) 2009 Elsevier Global Medical News. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.

奥兰多(EGMN)——用于糖尿病患者自动控制血糖水平的“人工胰腺”的开发正在逐步取得进展，其首先将尽可能地减少低血糖和高血糖事件的发生。

 

Aaron J. Kowalski博士在美国糖尿病学会年会上表示：“这种人工胰腺并非一种即用即可解决糖尿病问题的系统……这将是一种渐进的反复过程。”Kowalski博士是青少年糖尿病研究基金会(JDRF)血糖控制研究的助理副主席。该基金会正通过其人工胰腺项目资助大多“闭环”式胰岛素给药系统的开发。

 

当前研究的重点领域包括可最大限度减少高血糖和低血糖事件的系统，包括可预测即将发生的夜间低血糖并停止给药长达2 h的泵关闭系统。Kowalski博士在一次研讨会上表示，在英国上市的Medtronic Veo胰岛素泵已经具有这种功能，但由于监管问题，这种泵尚未在美国上市。

 

在现有技术条件下，夜间闭环控制已成可能，而完全自动的系统最终需要改进的传感器和胰岛素剂型，这将是一种同时包括高血糖素和胰岛素的双激素系统。

 

英国剑桥大学儿科和代谢科学研究所的Roman Hovorka博士报告了17例儿童和24例成人1型糖尿病患者应用夜间闭环式血糖控制的最新数据，该系统利用了他的研究团队根据自适应模型-预测控制开发的规则系统和现有传感器及胰岛素泵来控制血糖。

 

在应用闭环式系统的57个夜晚中，患者血糖控制在目标范围（71~145 mg/dl）的时间占77%，而在未用闭环式系统的胰岛素泵疗法下，患者在45夜晚中仅47%的时间血糖控制在目标范围。

 

美国波士顿Joslin糖尿病中心的心理学家Marilyn Ritholz博士报告了参与青少年糖尿病研究基金会资助的针对持续血糖监测临床研究的20例成人1型糖尿病患者对于应用持续血糖监测的态度的量化资料。

 

半结构化晤谈发现，应用持续血糖监测结果更佳的患者更趋向于采用一种解决问题的方式并利用回顾性资料来尝试和确定解决问题的方式，而不是仅依赖实时更新。来自配偶和其他亲人的支持也是获得良好结果的重要原因。相反，常对持续血糖监测中的数据和警示较敏感的患者往往控制结果不佳，同样配偶对该系统无兴趣或不支持的患者结果也不满意。

 

另外，对身体形象的看法似乎并不能预测结果会不会令人满意，其中的诸多问题仍需要进一步研究。Ritholz评论道：从患者的角度看，“持续血糖监测需要成为个人的一部分而不仅是一种医疗装置”。

 

Kowalski博士和Ritholz博士表示无利益冲突声明。Hovorka博士是Animas公司的顾问；并接受了来自MiniMed Medtronic公司、Abbott Diabetes Care公司和Smiths Medical公司的研究资助；并担任LifeScan公司、MiniMed Medtronic公司、Braun公司及Novo Nordisk公司的讲者；还获得了Becton Dickinson公司给予的许可费用。

 

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