Q&A | Howard Wolpert, M.D., on CGM in the Diabetes Clinic
Tuesday, September 14, 2010
A senior physician in the Joslin adult clinic and assistant professor at Harvard Medical School, Howard Wolpert, M.D., examines the best ways to adopt technology for type 1 diabetes management.
In June, Dr. Wolpert published an invited editorial in the New England Journal of Medicine about the promises and problems of continuous glucose monitoring (CGM) for people with type 1 diabetes.
How can CGM aid diabetes management?
The real potential of CGM is that you can bring the average glucose down into a low range without the same risk of running into low glucose.
With CGM, you have a probe in the skin that is continuously measuring the glucose levels. People get a readout on their receiver unit that tells them not only what their glucose level is but what direction the glucose level is going, which is even more important from the standpoint of managing diabetes. The other big benefit is that these devices have alarms that can alert a person if their glucose level is out of range. And some of the devices also have predictive alarms.
Additionally, the ability to get glucose readings after a meal can be helpful. People can see the effect of specific foods and make corresponding dietary changes that improve their glucose control.
What is the status of CGM adoption?
The devices only have been FDA-approved in the past three years. In Massachusetts, since June 2009, all three of the main insurers (Blue Cross, Harvard Pilgrim and Tufts), have had coverage for adults with type 1 diabetes. I was quite involved in some of those coverage discussions. Since then, the technology adoption here has really taken off; we have more than 550 patients using CGM.
What turns it into success for the person with diabetes?
We have a lot of clinical experience in terms of what are the key issues that people need to understand and how to stage the training process. We’ve been getting support both from the Scripps Foundation and the Thomas J. Beatson, Jr. Foundation for developing training materials.
We’ve been studying adult subjects from a clinical trial sponsored by the Juvenile Diabetes Research Foundation, in which both our adult and pediatric clinics participated, to try to tease out predictors of benefits of CGM. For example, we uncovered that people who are focused on examining their glucose data retrospectively did much better. So do people who have strong support from their significant others. We try to reinforce those aspects in the training materials.
Another issue we identified was that the way people respond to frustration is a predictor of whether they do well or not with CGM. People respond in a stoical, self-controlling manner tend to do better than people who get frustrated and anxious and angry.
Is one issue the sheer amount of information?
Yes, the patients need insights not just about the technical usage, but how do they interpret the information? People also need to integrate glucose trend data into their decision-making.
Another element is that CGM technology generates an enormous amount of glucose data, and health professionals can analyze that to tease out recommendations for improvements in insulin dosing. The big challenge is that it’s extremely time-consuming and there are very few health professionals who have much expertise in that. We’ve started a collaboration with Abbott Laboratories to develop analytical tools to help with the whole process of analyzing this data and making treatment recommendations.
Are expectations sometimes too high for today’s CGM?
This is still fairly rudimentary technology and there are a lot of frustrations that go along with using it. The problem is that everyone kind of looks at technology as a panacea where it’s just a tool. With all these tools, as great as they are and as helpful as they can be, it really comes down to the person with diabetes knowing how to use them and making the right treatment decisions themselves.