Accuracy of a Novel Non-Invasive technology based EZSCAN system for the diagnosis of diabetes mellitus in Chinese

Non-invasive blood glucose monitoring technology in diabetes management: review

Diabetes is one of the leading non-communicable diseases globally, adversely impacting an individual's quality of life and adding a considerable burden to the healthcare systems. The necessity for frequent blood glucose (BG) monitoring and the inconveniences associated with self-monitoring of BG, such as pain and discomfort, has motivated the development of non-invasive BG approaches. However, the current research progress is slow, and only a few BG self-monitoring devices have made considerable progress. Hence, we evaluate the available non-invasive glucose monitoring technologies validated against BG recordings to provide future research direction to design, develop, and deploy self-monitoring of BG with integrated emerging technologies. We searched five databases, Embase, MEDLINE, Proquest, Scopus, and Web of Science, to assess the non-invasive technology's scope in the diabetes management paradigm published from 2000 to 2020. A total of three approaches to non-invasive screening, including saliva, skin, and breath, were identified and discussed. We observed a statistical relationship between BG measurements obtained from non-invasive methods and standard clinical measures. Opportunities exist for future research to advance research progress and facilitate early technology adoption for healthcare practice. The results promise clinical validity; however, formulating regulatory guidelines could foresee the deployment of approved non-invasive BG monitoring technologies in healthcare practice. Further, research prospects are there to design, develop, and deploy integrated diabetes management systems with mobile technologies, data analytics, and the internet of things (IoT) to deliver a personalised monitoring system.

DS21, a new noninvasive technology, is effective and safe for screening for prediabetes and diabetes in Chinese population

BACKGROUND

Screening for prediabetes and asymptomatic diabetes is important for preventing development to an irreversible stage. The current diagnosis of prediabetes and diabetes is based on blood glucose or HbA1c (an invasive method). The aim of this study was to assess the efficacy and safety of DS21, a new noninvasive technology, for noninvasive screening for prediabetes and diabetes.

METHODS

A total of 939 subjects were divided into a normal control group (NC, n = 308), impaired glucose regulation group (IGR, n = 312), and diabetes (DM) group (n = 319). All subjects underwent the DS21 test, and mean hands-feet, hand, and feet conductance values were analyzed. The diagnostic accuracy of the conductance value was analyzed by receiver-operating characteristic (ROC) curve.

RESULTS

The conductance values for hands-feet, hands, and feet in the DM and IGR groups were significantly lower than those in the NC group (all P < 0.01). The area under the ROC curve  (AUCROC) for distinguishing NC/IGR was highest when using hands-feet conductance values (0.766 [95% confidence interval, CI 0.730, 0.803]). However, the AUCROCs of distinguishing NC/abnormal glucose metabolism (AGM, including IGR+DM), non-diabetes (NDM)/DM, and IGR/DM were highest when using conductance values for hands at 0.782 [95% CI 0.752, 0.812], 0.688 [95% CI 0.653, 0.723] and 0.573 [95% CI 0.528, 0.617], respectively (all P < 0.01). Hand conductance of values 75.0 (sensitivity 0.769, specificity 0.660), 77.1 (sensitivity 0.718, specificity 0.695), 68.4 (sensitivity 0.726, specificity 0.555), and 58.1 (sensitivity 0.384, specificity 0.744) were recommended as the screening thresholds for NC/AGM, NC/IGR, NDM/DM, and IGR/DM, respectively. A hand conductance value 66.0 was also recommended to distinguish NC/AGM due to its high sensitivity and high PPV. No adverse events occurred in the test.

CONCLUSIONS

DS21 is fast, noninvasive, low cost, reliable and safe, which makes it a feasible device for screening for prediabetes and diabetes, especially in a large population.

A formula based on autonomic test using EZSCAN and anthropometric data for diagnosis of DM in China

Clinical diagnosis of diabetes mellitus (DM) is time-consuming and invasive. This study aimed to investigate the efficacy and accuracy of EZSCAN in detecting impaired glucose tolerance (IGT) and diabetes mellitus (DM) in Chinese population, and explore a diagnosis formula based on an autonomic test using EZSCAN measurement and anthropometric data. Eligible subjects (n = 1547) had the following data collected: those of anthropometric and EZSCAN measurements and biochemical tests including FPG, OGTT, HbA1c, and serum lipid tests. The support vector machine (SVM) algorithm method was used to derive a diagnostic formula. In this study, 452 and 263 subjects were diagnosed with T2DM and IGT, respectively, while 832 had normal glucose tolerance (NGT). The sensitivity rates for the formula were 77.2% for T2DM and 80.4% for IGT. The diagnostic formula was found to correlate strongly with EZSCAN values. The diagnostic formula based on autonomic test and anthropometric data appears to be a convenient and accurate routine screening option in the Chinese population.

Contrast in the circadian behaviors of an electrodermal activity and bioimpedance spectroscopy

Probing the electrical response of the human body is minimally invasive and a promising area of investigation for future health care. The electrical responses of individuals may vary depending on daily physiological rhythms or environmental changes, which may hamper their prediction for pathological status. In this study, we observed circadian expressions via both alternating current (AC) and direct current (DC) electrical responses of the human body using bioelectrical impedance analysis (BIA) and electrodermal activity (EDA). In total, 14 healthy adults (9 males and 5 females) participated and were hospitalized for 2 nights with controlled caloric intake, sleep hours and residential conditions. The EDA data showed a significant circadian rhythm, but the BIA data did not show significant modulations during the measurement period. No difference was found between circadian changes in male and female participants. The acrophase of the EDA voltage response showed similar behavior with variations in the heart rate variability, with a resistance minimum occurring at approximately 4 pm, implying that the behavior of the EDA is probably affected by the sympathetic nerve response. Moreover, the resistance of the EDA varied by up to 15% from its mean value, which suggests that circadian variations cannot be neglected for the correct diagnosis of pathological conditions. In contrast, the BIA method did not show this circadian variation but showed independent results over the measurement period. This difference in performance implies that the DC and AC responses of the human body contain different electrophysiological information.

Value of EZSCAN parameters for diabetes screening in Chinese

OBJECTIVE

To study the parameters of EZSCAN as a screening tool for diabetes in Chinese.

METHODS

A total of 6,270 subjects participated in the study. All subjects underwent tests of EZSCAN, fasting plasma glucose (FPG), oral glucose tolerance test and HbA_1c.

RESULTS

1. All subjects were divided into 4 groups: the normal group, sugar metabolic abnormalities as low-risk group, middle-risk group and high-risk group. The difference of diabetes incidence among the 4 groups was statistically significant. With the increase of EZSCAN score, the prevalence of diabetes increased significantly. But there is no statistically difference between the low-risk group and the middle-risk group. 2. After adjustment for other variables, there is significantly positive relationship among EZSCAN risk score and the risk of diabetes. Meanwhile there is no statistically difference between the low-risk group and the middle-risk group. 3. The cut-off point of EZSCAN for diabetes was 44.5% with the sensitivity was 73.2% which was higher than of FPG and HbA_1c.

CONCLUSION

As EZSCAN-diabetes risk score increases, the risk of diabetes increases. EZSCAN can be used as a tool for screening for diabetes. At the best screening diabetes cut-off point value 44.5%, the sensitivity is higher than traditional method of FPG and HbA_1c.

Normative Values for Electrochemical Skin Conductances and Impact of Ethnicity on Quantitative Assessment of Sudomotor Function

BACKGROUND

Sudomotor dysfunction is one of the earliest pathophysiologic abnormalities in diabetes. Sudoscan™ (Impeto Medical, Paris, France) was developed as a noninvasive, rapid, and quantitative assessment of sudomotor function and has been shown to be sensitive in the detection of neuropathy. This global collaborative analysis aimed to establish reference values in healthy subjects of different ethnic groups, age, and gender, to define factors potentially affecting results, and to provide standardization of the methodology.

MATERIALS AND METHODS

Data from 1,350 generally healthy study participants who underwent sudomotor function testing were collected and analyzed. The relationship between age, height, weight, gender, glycemic and lipid profiles, ethnicity, and hand and foot electrochemical skin conductance (ESC) was assessed among subgroups of participants.

RESULTS

Lower mean hands and feet ESC values were observed in African American, Indian, and Chinese subjects (P < 0.0001). No participant discomfort or safety concern was reported in 1,376 tests. No significant difference in ESC was observed between women and men at the hands (75 [57-87] vs. 76 [56-89] μS; P = 0.35) or feet (83.5 [71-90] vs. 82.5 [70-91] μS; P = 0.12). The coefficient of correlation between right and left side ESC was r = 0.96, P < 0.0001 for hands and r = 0.97, P < 0.0001 for feet. A significant but weak correlation was observed between ESC and age: for hands, r = -0.17, P < 0.0001; for feet, r = -0.19, P < 0.0001.

CONCLUSIONS

A normative reference range was established in whites showing that there was no effect of sex or body mass index and a slight decrease in ESC with age. Ethnicity influenced ESC scores, but additional studies are necessary to validate this effect and determine its mechanism and impact on nerve function.

[Screening and prevention of diabetes]

A valid and efficient screening for individual diabetes risk is a highly welcomed tool in primary care and specialist medical practice. It is needed to detect early stages of diabetes risk and prediabetes and to start interventions that have the aim to prevent diabetes and also other chronic diseases from developing. The oral glucose tolerance test is the gold standard, but it is difficult to perform in an evidence-based manner in primary care. Furthermore, measuring fasting and 2-h postprandial glucose values detects only late stages of the pathophysiological development of type 2 diabetes. Interestingly, the 1-h glucose value is highly predictive of future diabetes risk, but is rarely used in primary care. Therefore, risk scores are commonly used to evaluate diabetes risk, but unfortunately, they generally do not mirror the relevance of increased risk due to the person's own lifestyle. Measuring waist circumference is another possibility, because the waist is directly associated with the amount of visceral fat, which again directly correlates with the pathophysiology of diabetes development. A further possibility is the EZSCAN™ technology. The EZSCAN™ is based on reverse iontophoresis, a new technology to detect very early forms of peripheral neuropathies, which are commonly associated with early diabetes risk stages. It is important to perform diabetes screening in a targeted manner, in both medical and paramedical environments, and it is mandatory to add targeted interventions, based on the screening evaluated diabetes risk.

A preliminary investigation of EZSCAN™ screening for impaired glucose tolerance and diabetes in a patient population

EZSCAN™ is a non-invasive technology that evaluates sweat gland dysfunction using electrochemical skin conductance measurements, providing an opportunity to determine the risk of impaired glucose tolerance (IGT) and diabetes mellitus (DM). This study was conducted with the aims of detecting IGT and DM and investigating the efficacy and cut-off points of the EZSCAN test in a patient population. The traditional serum and plasma glucose tests were used as comparators. In this cross-sectional study, 270 previously undiagnosed patients (180 women and 90 men) with a high risk of glucose metabolism disorders (≥45 years old) were enrolled. All patients underwent an oral glucose tolerance test (OGTT) and hemoglobin A1c (HbA1c), fasting plasma glucose (FPG) and EZSCAN tests. Forty (14.8%) patients had newly diagnosed DM (NDM), 79 (29.3%) had IGT and 151 (55.9%) had normal glucose tolerance. The EZSCAN values of these groups were 48±11, 47±11 and 34±13%, respectively. For all patients, the correlation coefficient of EZSCAN was 0.462 with the OGTT (P<0.001), 0.182 with the FPG test (P<0.001) and 0.379 with the HbA1c test (P<0.001). The EZSCAN cut-off point for the detection of IGT was 37% [sensitivity, 82%; specificity, 62%; area under the curve (AUC), 0.778], and the cut-off point for NDM was 50% (sensitivity, 53%; specificity, 59%; AUC, 0.528). This study demonstrated that the non-invasive EZSCAN system is an effective screening tool for the detection of glucose dysfunction in the population tested, and that its performance in detecting previously undiagnosed IGT is superior to its performance in detecting DM.

A novel shear reduction insole effect on the thermal response to walking stress, balance, and gait

Shear stresses have been implicated in the formation of diabetes-related foot ulcers. The aim of this study was to evaluate the effect of a novel shear-reducing insole on the thermal response to walking, balance, and gait. Twenty-seven diabetes peripheral neuropathy patients were enrolled and asked to take 200 steps in both intervention and standard insoles. Thermal foot images of the feet were taken at baseline (1) following a 5-minute temperature acclimatization and (2) after walking. Testing order was randomized, and a 5-minute washout period was used between testing each insole condition. Sudomotor function was also assessed. Gait and balance were measured under single and dual task conditions using a validated body worn sensor system. The mean age was 65.1 years, height was 67.3 inches, weight was 218 pounds, and body mass index was 33.9, 48% were female, and 82% had type 2 diabetes. After walking in both insole conditions, foot temperatures increased significantly in standard insoles. The intervention insole significantly reduced forefoot and midfoot temperature increases (64.1%, P = .008; 48%, P = .046) compared to standard insoles. There were significant negative correlations with sudomotor function and baseline temperatures (r = .53-.57). The intervention demonstrated 10.4% less gait initiation double support time compared to standard insoles (P = .05). There were no differences in static balance measures. We found significantly lower forefoot and midfoot temperature increases following walking with shear-reducing insoles compared to standard insoles. We also found improvements in gait. These findings merit future study for the prevention of foot ulcer.

Association of EZSCAN values with arterial stiffness in individuals without diabetes or cardiovascular disease

Background

The EZSCAN test was recently developed to screen for early dysglycemia through an assessment of sudomotor function. Given the associations of dysglycemia and autonomic dysfunction with the development of arterial stiffness, EZSCAN may also detect early arterial stiffness. The aim of this study was to investigate the association of EZSCAN with arterial stiffness across blood glucose levels.

Methodology and Principal Findings

A total of 5532 participants without diabetes or established cardiovascular disease were evaluated with EZSCAN. Their central systolic blood pressure (cSBP), brachial-ankle pulse wave velocity (baPWV), and ankle-brachial index (ABI) were also measured. Multivariate linear regression analyses were used to assess the association between the EZSCAN value and the cSBP, baPWV, and ABI measurements in all of the participants, with additional subgroup analysis that separated participants into a normal glucose tolerance (NGT) group and an impaired glucose regulation (IGR) group. The frequency of the IGRs increased with quartiles of the EZSCAN value (P for trend <0.0001). The levels of cSBP and baPWV increased while the levels of ABI decreased across quartiles of EZSCAN value in both NGT and IGR individuals (P for trend <0.0001 for all). In multivariable analyses, the EZSCAN value was positively associated with cSBP (log-transformed beta = 8.20, P<0.0001) and baPWV (log-transformed beta = 1.82, P<0.0001) but inversely associated with ABI (log-transformed beta = −0.043, P<0.0001) and was independent of conventional factors. Further adjustment for fasting and postprandial glucoses did not attenuate the associations. The results were also unchanged when stratified by IGR.

Conclusions and Significance

The EZSCAN results were associated with arterial stiffness independent of conventional factors, blood glucose levels, and glucose tolerance status, suggesting a probable link between the EZSCAN value and arterial stiffness through autonomic dysfunction. The EZSCAN test may help us detect the development of arterial stiffness in high risk individuals to prevent unfavorable cardiovascular events.

Assessment of small fiber neuropathy to predict future risk of type 2 diabetes

OBJECTIVE

Sudomotor dysfunction due to small fiber neuropathy can be observed very early in pre-diabetes. The aim of this study was to assess the predictive power of EZSCAN, a non invasive, quick and simple measurement of sudomotor function to identify glucose impairment.

RESEARCH DESIGN AND METHODS

The study was performed in 76 German subjects at risk of diabetes. Glucose metabolism was assessed by using, oral glucose tolerance test (OGTT) at baseline and after 2 year follow-up. Sudomotor function was evaluated by measuring hand and foot electrochemical sweat conductances to calculate a risk score.

RESULTS

At baseline, 38 patients had normal glucose tolerance (NGT), 34 had pre-diabetes (impaired fasting glucose, IFG and/or impaired glucose tolerance, IGT) and 4 had newly diagnosed type 2 diabetes. The AUC values for FPG, 2h-OGTT glucose, 1h-OGTT glucose, HbA1C and EZSCAN score to predict pre-diabetes were 0.50, 0.65, 0.64, 0.72 and 0.76, respectively. Subjects having a moderate or high EZSCAN score (>50) at baseline had a substantially increased risk for having IFG and/or IGT at follow-up visit presented by an odds ratio of 12.0 [1.4-100.5], the OR for having 1h-OGTT ≥ 8.6mmol/L at follow-up was 9.8 [1.0-92.8] and for having HbA1C ≥ 5.7% was 15.7 [1.9-131.5] compared to subjects with low EZSCAN risk.

CONCLUSIONS

This preliminary study, which must be confirmed in a larger population, shows that EZSCAN risk score is associated with diabetes progression which have implications for prevention and disease management.

Evaluation of EZSCAN as a screening tool for impaired glucose metabolism

AIMS

To evaluate the performance of EZSCAN as a screening tool for impaired glucose metabolism (IGM), including impaired glucose tolerance, impaired fasting glucose and undiagnosed diabetes in a Chinese population.

METHODS

876 subjects participated in the study. All subjects underwent tests of EZSCAN, glycated hemoglobin, fasting plasma glucose (FPG), and oral glucose tolerance test (OGTT). Correlation of electrical skin conductance (ESC) with glucose level was evaluated by Pearson correlation coefficient. EZSCAN performance was assessed by receiver operating characteristic curve.

RESULTS

Among the 876 subjects, 53% had normal glucose tolerance (NGT), and 47% had IGM. The ESC for the hands and feet was 72 ± 10 μS and 75 ± 7 μS, respectively, in NGT group; and 64 ± 13 μS and 67 ± 11 μS, respectively, in IGM group. The ESC at hands and feet was significantly correlated with both 2h-OGTT and FPG (p<0.001). NGT group demonstrated a EZSCAN score of 33 ± 11%, which is significantly lower than that of IGM group (44 ± 12%, p<0.001). The cut-off point of EZSCAN for IGM detection was 40% with a sensitivity of 80% and a specificity of 72%.

CONCLUSIONS

EZSCAN is a useful screening tool for identifying subjects at increased risk for impaired glucose metabolism in prediabetes and diabetes. Diagnostic laboratory test should be performed in subjects with EZSCAN scores greater than 40%.

Estimation of blood glucose by non-invasive infrared thermography for diagnosis of type 2 diabetes: an alternative for blood sample extraction

The present study aims to estimate and validate the glycated haemoglobin (HbA(1c)) using non-contact infrared thermography. The diagnostic threshold was set as (HbA(1c)≥48 mmol/mol). The optimal regression model [r=0.643, p=0.000] was achieved from the significant variables correlating with the HbA(1c) and the validation was performed against the bio-chemical assay to indicate the sensitivity, specificity, positive predictive value, negative predictive value and with an accuracy of [90%, 55%, 65%, 85% and 72%] respectively. The non-invasive core body temperature measurement at the inner canthi of eye [r=-0.462, p<0.01] indicated negative correlation with HbA(1c), that signifies the early metabolic changes. In type 2 diabetes, the core body temperature decreases with a decrease in the body metabolism. Thereby, a truly non-invasive infrared thermography could be used for obtaining the accurate HbA(1c) with no blood sample extraction; further, it could be used as the preferred diagnostic tool for type 2 diabetes.

Autonomic test by EZSCAN in the screening for prediabetes and diabetes

BACKGROUND

Autonomic neuropathy is common in diabetics and may occur in prediabetes. A new and noninvasive autonomic test-EZSCAN evaluates sudomotor function precisely. No generally accepted EZSCAN thresholds to screen for prediabetes and diabetes have been defined.

METHODOLOGY AND PRINCIPAL FINDINGS

Cross-sectional study of 5, 824 Chinese adults aged 40 and older was conducted in Shanghai, China. We used EZSCAN to evaluate autonomic function in different glucose status and screen for prediabetes and diabetes. The prevalence of prediabetes and diabetes were 21.9% and 17.5% respectively. Compared with the lowest quintile, the highest quintile of EZSCAN value had odds ratios for having dysglycemia (prediabetes or diabetes) of 2.08 (95% CI 1.67-2.58) in total population, 2.89 (95% CI 2.06-4.05) in men and 1.70 (95% CI 1.28-2.25) in women after adjustment for confounding factors. EZSCAN value improved the areas under ROC curve for detection of dysglycemia or diabetes beyond the contribution of conventional risk factors by 0.8% and 12.9%. The cut-off point of EZSCAN value higher than 30% provided reasonable sensitivities (70.3-83.7%) to detect dysglycemia not only in total population regardless of sex but also in individuals with high risk of developing diabetes.

CONCLUSIONS AND SIGNIFICANCE

EZSCAN value higher than 30% indicate an increased risk of prevalent prediabetes and diabetes, suggesting that subjects with EZSCAN ≥30% should be further evaluated by oral glucose tolerance test. The improvement of EZSCAN for diabetes detection was still of limited clinical relevance. Thus the clinical application value of EZSCAN is needed to be explored in future studies.

Accessing autonomic function can early screen metabolic syndrome

Background

Clinical diagnosis of the metabolic syndrome is time-consuming and invasive. Convenient instruments that do not require laboratory or physical investigation would be useful in early screening individuals at high risk of metabolic syndrome. Examination of the autonomic function can be taken as a directly reference and screening indicator for predicting metabolic syndrome.

Methodology and Principal Findings

The EZSCAN test, as an efficient and noninvasive technology, can access autonomic function through measuring electrochemical skin conductance. In this study, we used EZSCAN value to evaluate autonomic function and to detect metabolic syndrome in 5,887 participants aged 40 years or older. The EZSCAN test diagnostic accuracy was analyzed by receiver operating characteristic curves. Among the 5,815 participants in the final analysis, 2,541 were diagnosed as metabolic syndrome and the overall prevalence was 43.7%. Prevalence of the metabolic syndrome increased with the elevated EZSCAN risk level (p for trend <0.0001). Moreover, EZSCAN value was associated with an increase in the number of metabolic syndrome components (p for trend <0.0001). Compared with the no risk group (EZSCAN value 0–24), participants at the high risk group (EZSCAN value: 50–100) had a 2.35 fold increased risk of prevalent metabolic syndrome after the multiple adjustments. The area under the curve of the EZSCAN test was 0.62 (95% confidence interval [CI], 0.61–0.64) for predicting metabolic syndrome. The optimal operating point for the EZSCAN value to detect a high risk of prevalent metabolic syndrome was 30 in this study, while the sensitivity and specificity were 71.2% and 46.7%, respectively.

Conclusions and Significance

In conclusion, although less sensitive and accurate when compared with the clinical definition of metabolic syndrome, we found that the EZSCAN test is a good and simple screening technique for early predicting metabolic syndrome.