Please can you tell us a little bit about type 1 diabetes and why patients need to measure their blood sugar?
Type 1 diabetes is a disorder in which the body makes proteins (antibodies) against the cells in the pancreas that produce insulin, destroying those cells. As a result, individuals are unable to secrete insulin to normalize blood sugar and hyperglycemia results.
Patients with type 1 diabetes need to check their blood sugars several times daily to know if their current insulin doses are effective and to have information to provide to their physicians who adjust their insulin therapy.
How often do type 1 diabetes patients traditionally need to monitor their blood sugar?
Ideally blood sugars should be monitored at least 4 times/daily—fasting (before breakfast), before lunch, before dinner, and at bedtime. However, many patients monitoring their blood sugars more frequently than this, especially if they have a lot of very low (hypoglycaemia) or very high (hyperglycemia) blood sugars.
Please could you tell us a little bit about the conventional methods for monitoring blood sugar?
Conventional methods involve the patient pricking his or her finger, placing blood on a test strip, and inserting the test strip into a blood glucose monitor, called a glucometer, to measure blood sugar.
How do the new blood sugar monitors that you have been researching work?
The real-time continuous glucose monitoring systems track blood sugar levels continuously through a small device, called a glucose sensor, attached to the abdomen. Those readings are then sent to a device worn at the waist that displays the readings. A graphical display shows blood sugar trends and the sensor has alarms that can be set to notify patients in advance of high and low blood sugars.
Patients still have to check their blood sugars 2-4 times daily to make sure the device is calibrated but it decreases the frequency of checks for individuals checking their sugars more often than this.
How did this new technology compare to the conventional methods of monitoring blood sugar?
In our meta-analysis, individuals who used the new technology (real-time continuous glucose monitoring system) had better blood sugar control than those who used the conventional method (fingersticks).
In addition, individuals who used the continuous glucose monitoring system with an insulin pump had better blood sugar control than those who used fingersticks with multiple daily shots. Rates of low blood sugar (hypoglycaemia) were the same with both technologies.
Will these new technologies suit everyone or only certain patients?
Our study showed a benefit in patients with type 1 diabetes, particularly those who were most adherent to wearing the device (i.e. those who wore the sensor at least 60% of the time).
There are currently no data on whether this new technology is beneficial in individuals with type 2 diabetes or in pregnant women with pre-existing diabetes. These studies will need to be conducted in the future.
How soon will these technologies be available to the general public?
These technologies are already available to the general public.
Will the expense of these new technologies be off-putting for patients?
The real-time continuous glucose monitoring system and the supplies costs approximately $5,000/year and is not covered by all insurance companies yet, so this will determine device use in various patient populations with type 1 diabetes.
How do you see the future of blood sugar monitoring progressing?
Current on-going research is trying to determine how to develop a closed-loop system in which the continuous glucose monitoring device will be able to communicate with and determine insulin adjustments for the insulin pump in an automated manner. Researcher also continue to work on improving the accuracy of the devices and making them easier for patients to use.
Do you have any plans for further research into this area?
We are currently preparing a Future Research Needs Report for the Agency for Healthcare Research and Quality in which we will identify current gaps in research and what future studies of these devices should examine.
Where can readers find more information?
Golden SH, Brown T, Yeh HC, Maruthur N, Ranasinghe P, Berger Z, Suh YD, Wilson LM, Haberl EB Bass EB: Methods for Insulin Delivery and Glucose Monitoring: Comparative Effectiveness. Comparative Effectiveness Review No. 57 (Prepared by Johns Hopkins Evidence-based Practice Center under Contract No. HHSA-290-2007-10061-I.) AHRQ Publication No. 12-EHC036-EF. Rockville, MD: Agency for Healthcare Research and Quality. July 2012 (http://www.effectivehealthcare.ahrq.gov/glucose.cfm).
About Dr. Sherita Hill Golden
Dr. Sherita Hill Golden is an Associate Professor of Medicine in the Division of Endocrinology and Metabolism at the Johns Hopkins University School of Medicine. She also holds joint appointments in the Welch Center for Prevention, Epidemiology, and Clinical Research and in the Department of Epidemiology at the Johns Hopkins Bloomberg School of Public Health.
She graduated Phi Beta Kappa and summa cum laude from the University of Maryland, College Park and Alpha Omega Alpha from the University of Virginia School of Medicine before training in Internal Medicine and Endocrinology and Metabolism at the Johns Hopkins Hospital. During her fellowship in Endocrinology, she received a Master of Health Science degree in Clinical Epidemiology from the Johns Hopkins University Bloomberg School of Public Health.
Dr. Golden’s primary research interest centers around identifying endocrine risk factors associated with the development of diabetes and cardiovascular disease through the incorporation of measures of hormonal function into the design of clinical trials of cardiovascular risk modification, observational studies of incident cardiovascular disease and diabetes, and studies evaluating diabetic complications.
Her current research focuses on studying the neuroendocrine response to chronic psychological stress as a risk factor for diabetes and cardiovascular disease. She has authored and co-authored over 60 original articles and book chapters in the areas of diabetes and cardiovascular disease epidemiology.
She is a former Robert Wood Johnson Minority Medical Faculty Career Development Award recipient and her current research is funded through the National Institute of Diabetes, Digestive, and Kidney Diseases and the National Heart, Lung, and Blood Institute. She is the director of the Johns Hopkins Inpatient Diabetes Management Service and serves as Chairperson of the Glucose Steering Committee for Johns Hopkins Hospital.
She is also currently Chairperson of the Epidemiology and Biostatistics Interest Group for the American Diabetes Association and Chairperson of the Diabetes Committee for the American Heart Association’s Council of Nutrition, Physical Activity, and Metabolism.