Urine and blood sugar tests are the currently preferred screening tools for diabetes mellitus, but these tests lack accuracy and convenience. Although the glucose tolerance test (GTT) is more accurate, it is a tedious and painful method, as it requires fasting, ingestion of a glucose load, and collection of multiple blood samples. Now, in a paper published in the September 2007 issue of the Proceedings of the National Academy of Sciences, researchers from the University of California, Irvine, USA have reported that a new breath-analysis testing can be used as an accurate non-invasive method for monitoring blood sugar levels in diabetes.
Using a chemical analysis method developed originally for air-pollution testing, the group, led by Galassetti, a diabetes researcher from the General Clinical Research Center (GCRC) at UC Irvine, found significantly higher concentrations of methyl nitrates in the air exhaled by children with type-1 diabetes during hyperglycemic episodes. They conducted the study by collecting air samples from 10 children with type-1 diabetes mellitus in the hyperglycemic state. The team further analyzed the breath sample for more than 100 gasses at parts-per-trillion levels, and observed a corresponding increase in the methyl nitrate concentrations with increasing blood glucose levels. The scientists speculate that the methyl nitrate could be a by-product of increased oxidative stress, arising due to the presence of elevated levels of fatty acids in the blood. The methyl nitrate, which is present at very low concentrations in ambient air, normally occurs only at very low parts-per-trillion levels in the exhaled air of a healthy individual. Currently, they are investigating the correlation between other gases and hyperglycemia as well.
In a paper published in the 2006 issue of the Proceedings of the SPIE, Massick and co-workers observed that elevated levels of acetone in breath is a reliable indicator of dietary imbalances, or diseased states, such as untreated diabetes. Based on the study, they developed a novel method of acetone detection by allowing the breath samples to pass through a reactor filled with solid hydroxylamine (HA) hydrochloride and the amount of HCl produced by the reaction between acetone and HA was measured using a sensitive near-infrared diode laser spectroscopy.
Using the company’s proprietary Spectroscopic Advanced Glycation Endproducts detection technology (SAGE), researchers at VeraLight Inc developed a portable, noninvasive diabetes-screening device known as Scout DS™. A study conducted by Maynard and colleagues (Diabetes Care, 2007) on 351 subjects using the Scout DS prototype had demonstrated that the novel screening system outperformed the conventional tests like fasting plasma glucose (FPG) test and the HbA1C test by detecting 29% more patients with type 2 diabetes and impaired glucose tolerance (IGT) than FPG, and 17% more cases than the HbA1C test. The system utilizes fluorescence spectroscopy to noninvasively detect abnormal concentrations of skin biomarkers, known as advanced glycation endproducts (AGEs), in the subject’s forearm. The researchers are planning to introduce the investigational device in the US market around the second half of 2008.
Worldwide, over 194 million people are estimated to have diabetes, and as per reports of the World Health Organization, the numbers are expected to rise to more than 300 million by the end of 2025. The breath-analysis testing will certainly revolutionize the screening and management of diabetes, as it will not only allow easier detection of diabetes, but also help in monitoring blood sugar levels more conveniently and avoiding painful needle-pricks.
About VeraLight – VeraLight, headquartered in Albuquerque, New Mexico, emerged as an independent spinout of InLight Solutions. The privately held medical instrumentation company is focused exclusively on developing noninvasive systems for screening diabetes mellitus.
References
1. Breath analysis offers potential for non-invasive blood sugar monitoring in diabetes. UCI. Last accessed on September 27, 2007.
2. Massick SM and Vakhtin A. Breath acetone detection. Proceedings of SPIE. 2006 October 17;6386.
3. Maynard JD, Rohrscheib M, Way JF, et al. Noninvasive Type 2 Diabetes Screening. Diabetes Care. 2007 March 2; 30:1120-1124.
4. About VeraLight. VeraLight. Last accessed on September 27, 2007.
